SEC Form DEF 14A filed by PLUS THERAPEUTICS Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant  ☐

Check the appropriate box:

PLUS THERAPEUTICS, INC.

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

6420 Levit Green Boulevard, Suite 310

Houston, Texas 77021

March 31, 2026

To Our Stockholders:

This year holds the potential to be the most transformational in Company history. Commercializing our first products, bringing our lead drug to registrational trials and relaunching with a new and unique mission to improve survival in central nervous cancer is all in our plan for the year. In the past few years, through multiple transactions, we have built a foundation for improved patient outcomes and building stockholder value.

In our first full year operating three integrated businesses, specifically: therapeutics, diagnostics, and advanced data analytics, we have already made major strides. I would like to dive deeper into each focus area and provide guidance for the year.

Our lead investigational radiotherapeutic drug, REYOBIQTM, is being evaluated for three central nervous system (CNS) cancers—leptomeningeal metastases (LM), pediatric brain cancer (PBC), and recurrent glioblastoma (rGBM). There is a growing epidemic of brain cancer led largely by metastatic diseases such as LM, which is tumor in the fluid space around the brain. In 2026, building on the completed ReSPECT-LM safety trial for patients with LM and an end of phase meeting with the FDA last year, we are enrolling in an optimal dose/interval trial leading into a Phase 2 expansion trial. We anticipate reporting data in the third quarter of 2026. In our ongoing glioblastoma Phase 2 trial, ReSPECT-GBM, we intend to complete enrollment, present data and schedule an end of phase meeting with the FDA to seek alignment on pivotal trial design by Q4 2026. Finally, we expect to begin enrollment in the ReSPECT-PBC Phase 1 trial in 2026. To be pivotal trial ready in early 2027, we are shifting our principal REYOBIQ radiotherapeutic manufacturing to SpectronRx, which will provide us with commercial scale.

To meet the clinical demands of the growing epidemic in brain cancer, better diagnostics are needed to both identify affected patients and help caregivers manage the disease. This led to our recent launch of our CNSide® CSF diagnostic platform. In 2026, we intend to scale manufacturing, testing capabilities and sales related functions. Key objectives in 2026 are to expand the payor base to at least 150 million covered lives, obtain Medicare coverage, substantially increase the customer base, bring new testing capabilities to market, and drive testing utilization. Based on present forecast, our CNSide business unit may breakeven by 2027.

Finally, we intend to implement advanced data analytics across the Company. Beyond the routine and generalized use of artificial intelligence, in 2026, we intend to implement a variety of business-specific uses in both our diagnostic and therapeutic operations. In aggregate, these initiatives should improve efficiency, reduce costs, limit the need to expand our workforce, and drive pipeline innovation. We plan to execute this plan through both internal processes and through strategic partnerships. We will provide updates as key milestones are reached.

Behind the scenes, we have taken steps to strengthen the Company’s capitalization by leveraging our growing CNSide business and advancing clinical pipeline, with focus on maximizing value for our stockholders. On behalf of our employees, management and directors, I would like to express our deep appreciation to our stockholders and partners for their help and support in 2025 and beyond.

NOTICE OF 2026 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON MAY 14, 2026

Dear Plus Therapeutics, Inc. Stockholder:

You are cordially invited to attend the 2026 Annual Meeting of the Stockholders of Plus Therapeutics, Inc. (the “Annual Meeting”). The Annual Meeting will be held on May 14, 2026, commencing at 9:00 a.m. (Eastern Time), and will be a completely virtual meeting of stockholders.

The items of business for the meeting are to:

The board of directors (“Board”) recommends that stockholders (a) elect each board member nominee; and (b) vote to approve items (ii), (iii) and (iv).

In light of our successful virtual annual meetings of stockholders in the past five years, the Annual Meeting will be held only via live webcast again this year. We believe that the virtual meeting format also expands stockholder access, participation and improves communications, and we encourage you to attend online and participate.

You will be able to attend and participate in the Annual Meeting online, vote your shares electronically, and submit your questions prior to and during the meeting by visiting: www.virtualshareholdermeeting.com/PSTV2026. To vote at the meeting, you must have your control number that is shown on your proxy card. There will not be a physical meeting location and you will not be able to attend the annual meeting in person.

Only stockholders of record at the close of business on March 18, 2026, are entitled to notice of and to vote at the Annual Meeting. For ten (10) days prior to the Annual Meeting, a complete list of stockholders entitled to vote at the Annual Meeting will be available at the Corporate Secretary’s office at 6420 Levit Green Boulevard, Suite 310, Houston, Texas 77021. On or around April 2, 2026, we began mailing our stockholders a Notice of Internet Availability, as permitted under applicable Securities and Exchange Commission (“SEC”) rules. The Notice of Internet Availability indicates how to access our proxy materials on the Internet. By furnishing the Notice of Internet Availability, we are lowering our costs and reducing the environmental impact of our Annual Meeting.

You are cordially invited to attend the Annual Meeting live via the Internet. It is important that your shares are represented at the Annual Meeting. Even if you plan to attend the Annual Meeting live via the Internet, we hope that you will promptly vote by dating, signing and returning the enclosed proxy card or vote via the Internet or by telephone. This will not limit your ability to attend or vote during the Annual Meeting.

Plus Therapeutics, Inc.

Houston, Texas, USA

March 31, 2026

TABLE OF CONTENTS

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Proxy Statement on Schedule 14A (the “Proxy Statement”) contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), which statements involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or our future financial or operating performance and may include statements concerning, among other things, our business strategy, our governance initiatives and impacts of our compensation program.

In some cases, you can identify forward-looking statements by words such as “anticipate,” “believe,” “consider,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “should” or “will” or the negative or plural of these words or other similar terms or expressions. All statements other than statements of historical fact are forward-looking statements, which speak only as of the date they are made, and are not guarantees of future performance.

These forward-looking statements are not guarantees of future performance and involve a number of assumptions, risks and uncertainties that could cause actual results to differ materially from expected results. As a result, you should not put undue reliance on any forward-looking statement. These forward-looking statements are included throughout this Proxy Statement. Factors that could cause our actual results to differ materially from those expressed or implied in such forward-looking statements include, but are not limited to, to changes in global, regional or local political, economic, business, competitive, market, regulatory and other factors, many of which are beyond our control, as well as the risk factors discussed in the “Risk Factors” section of our Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission (the “SEC”) on March 12, 2026 (the “2025 Annual Report”), and in other subsequent filings with the SEC. Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove to be incorrect, our actual results may vary in material respects from what we may have expressed or implied by these forward-looking statements. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and we caution that you should not place undue reliance on any of our forward-looking statements. Any forward-looking statement made by us in this Proxy Statement speaks only as of the date on which we make it. We undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future developments or otherwise, except as may be required by applicable securities laws. You should read this Proxy Statement with the understanding that our actual future results, performance, and events and circumstances may be materially different from what we expect.

6420 Levit Green Boulevard, Suite 310

Houston, Texas 77021

PROXY STATEMENT

2026 ANNUAL MEETING OF STOCKHOLDERS

To Be Held on May 14, 2026 at 9:00 a.m. (Eastern Time)

General Information

Our Board is soliciting your proxy to vote at the Annual Meeting, for the purposes set forth in this Proxy Statement. This Proxy Statement includes information that we are required to provide to you under the rules of the SEC and that is designed to assist you in voting your shares. The Annual Meeting will be held virtually via a live webcast on the Internet on Thursday, May 14, 2026 at 9:00 a.m. (Eastern Time). For purposes of attendance at the Annual Meeting, all references in this Proxy Statement to “present in person” or “in person” shall mean virtually present at the Annual Meeting.

We have fixed the close of business on March 18, 2026 as the record date for the determination of the stockholders entitled to notice of and to vote at the Annual Meeting (the “Record Date”). Only holders of record of shares of our common stock (“Common Stock”) on that date are entitled to notice of and to vote at the Annual Meeting.

You will be able to attend and participate in the Annual Meeting online, vote your shares electronically, and submit your questions prior to and during the meeting by visiting: www.virtualshareholdermeeting.com/PSTV2026. To vote at the meeting, you must have your control number that is shown on your proxy card. There will not be a physical meeting location and you will not be able to attend the annual meeting in person.

In this Proxy Statement, we refer to Plus Therapeutics Inc. as “Plus,” the “Company, “we,” “us” or “our” and the board of directors of Plus as “our Board.” Our 2025 Annual Report accompanies this Proxy Statement. Information contained on, or that can be accessed through, our website is not intended to be incorporated by reference into this Proxy Statement and references to our website address in this Proxy Statement are inactive textual references only.

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS,

ANNUAL MEETING AND VOTING

What is a proxy statement and why has this Proxy Statement been provided to me?

A proxy statement is a document that the SEC regulations require us to give you when we ask you to provide a proxy to vote your shares at the Annual Meeting. Among other things, this Proxy Statement describes the proposals on which stockholders will be voting and provides information about us. You are viewing, or have received, these proxy materials because our Board is soliciting your proxy to vote your shares of Common Stock at the Annual Meeting. This proxy statement includes information that we are required to provide to you under the rules of the SEC and that is designed to assist you in voting your shares. Instructions regarding how you can vote are contained on the proxy card included in the proxy materials. We will use the proxies received in connection with the Annual Meeting to:

What are the voting recommendations of our Board?

Our Board recommends that you vote “FOR” each director nominee named in Proposal 1, “FOR” the ratification of the selection of CBIZ CPAs, P.C. as our independent registered public accounting firm described in Proposal 2, “FOR” the approval, on an advisory basis, of the compensation of our named executive officers in Proposal 3, and “FOR” the approval of the amendment and restatement of the 2020 Stock Incentive Plan in Proposal 4.

What is a proxy?

A proxy is your legal designation of another person to vote the stock you own. That designee is referred to as a proxy holder. Designation of a particular proxy holder can be effected by completion of a written proxy card, or by voting via the Internet or by telephone. If you return a proxy card, or vote by phone or Internet, our President and Chief Executive Officer, Marc H. Hedrick, M.D., and our Chief Financial Officer, Andrew Sims, will act as your designated proxy holder at the Annual Meeting.

How can I attend and ask questions during the Annual Meeting?

The Annual Meeting will be a virtual meeting of stockholders, which will be conducted exclusively by webcast. You are entitled to participate in the Annual Meeting only if you were a stockholder of the Company as of the close of business on March 18, 2026, or if you hold a valid proxy for the Annual Meeting.

No physical meeting will be held. You will be able to attend the Annual Meeting online and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/PSTV2026. Stockholders attending the Annual Meeting will be afforded the same rights and opportunities to participate as they would at an in-person meeting. You also will be able to vote your shares online by attending the Annual Meeting webcast. To participate in the Annual Meeting, you will need the sixteen- (16) digit control number provided on your proxy card. For more information, review the information included on your proxy card, or the instructions that accompanied your proxy materials. If you are the beneficial owner of your shares, your control number is included with your voting instruction card and voting instructions received from your brokerage firm, bank or other nominee.

The Annual Meeting will begin promptly at 9:00 a.m. (Eastern Time) on May 14, 2026. We encourage you to access the meeting prior to the start time, leaving ample time for the check in. Please follow the instructions in this Proxy Statement and on your proxy card.

We will hold a live question and answer session, during which we intend to answer appropriate questions submitted by stockholders during the Annual Meeting that are pertinent to the Company and the Annual Meeting matters. If you would like to submit a question during the Annual Meeting, you may log in at www.virtualshareholdermeeting.com/PSTV2026 using your control number, type your question into the “Ask a Question” field, and click “Submit.” To help ensure that we have a productive and efficient meeting, and in fairness to all stockholders in attendance, you will also find posted our rules of conduct for the Annual Meeting when you log in prior to its start. We will answer as many questions, submitted in accordance with our rules of conduct, as practicable in the time allotted.

What is the difference between a stockholder of record and a beneficial owner who holds stock in street name?

You are a stockholder of record, or a “registered holder,” if your shares are registered in your own name through our transfer agent. If you have a stock certificate, you are also a stockholder of record. You are a beneficial owner of our stock in street name if you hold your shares through a broker, bank or other third-party institution (in this situation, the banks, brokers, etc., are the stockholders of record). The vast majority of our stockholders hold their shares in street name.

Why did I receive a notice in the mail or by email regarding the Internet availability of proxy materials instead of printed proxy materials?

In accordance with the rules of the SEC, instead of mailing a printed copy of our proxy materials to our stockholders, we have elected to furnish these materials by providing access to these documents over the Internet. Accordingly, on or about April 2, 2026, we sent a Notice of Internet Availability of Proxy Materials (“Notice of Internet Availability”) to our stockholders of record and beneficial owners. All stockholders have the ability to access the proxy materials on a website referred to in the Notice of Internet Availability.

What does it mean if I receive more than one set of proxy materials or more than one email?

It means you have multiple accounts at the transfer agent or with banks, brokers or other nominees. If you received more than one Notice of Internet Availability, you may need to enter separate electronic control voting numbers when voting by the Internet to ensure that all of your shares have been voted. If you received more than one proxy card, vote instruction form or email, please complete and provide your voting instructions for all proxy cards, vote instruction forms and emails that you receive.

How can I get electronic access to the proxy materials?

The Notice of Internet Availability provides you with instructions regarding how to (1) view our proxy materials for the Annual Meeting on the Internet; (2) vote your shares after you have viewed our proxy materials; and (3) request a printed copy of the proxy materials.

Our proxy materials are also available online at www.proxyvote.com.

What different methods can I use to vote?

Stockholder of Record: Shares Registered in Your Name. Stockholders who are a registered holder may vote by virtually attending the proxy meeting, submitting votes electronically over the Internet, by telephone or by completing and mailing a proxy card. The website identified on the proxy card or Notice of Internet Availability provides specific instructions on how to vote electronically over the Internet. Those stockholders who receive a paper proxy by mail, and who elect to vote by mail, should complete and return the mailed proxy card in the prepaid and addressed envelope that was enclosed with the proxy materials. Stockholders who vote over the Internet or by telephone need not return a proxy card or voting instruction form by mail, but may incur costs, such as usage charges, from telephone companies or Internet service providers. Even if you have submitted a proxy before the meeting, you may still attend online and vote during the meeting. In such case, your previously submitted proxy will be disregarded. For more information, see the question below titled “How can I change my vote or revoke my proxy after submitting a proxy?”

Beneficial Owner: Shares Held on Your Behalf by a Brokerage Firm, Bank, or Other Nominee. If you are the beneficial owner of stock held in street name, follow the instructions from your broker, bank or other nominee to vote your shares.

Stockholders who have previously elected to access our proxy materials and annual report electronically over the Internet will receive a Notice of Internet Availability with information on how to access the proxy information and voting instructions.

Only proxy cards and voting instruction forms that have been signed, dated and timely returned and only proxies that have been timely voted electronically or by telephone will be counted in the quorum and voted.

You may also vote your shares at the Annual Meeting. If you are a registered holder you must join live online at www.virtualshareholdermeeting.com/PSTV2026. The webcast will start at 9:00 a.m. (Eastern Time). You may vote and submit questions while attending the meeting online. You will need the control number included on your proxy card (if you received a printed copy of the proxy materials) to vote during the meeting.

If you receive more than one Notice of Internet Availability, proxy card or voting instruction form because your shares are held in multiple accounts or registered in different names or addresses, please vote your shares held in each account to ensure that all of your shares will be voted.

A representative of an independent inspector of election, who we retained, will tabulate and certify the votes.

What if I have technical difficulties or trouble accessing the Annual Meeting?

We will have technicians ready to assist you with any technical difficulties you may have accessing the Annual Meeting. If you encounter any difficulties accessing the Annual Meeting during the check-in or meeting time, please call the technical support number that will be posted at www.virtualshareholdermeeting.com/PSTV2026.

Will a list of stockholders of record as of the Record Date be available?

A list of our stockholders of record as of the close of business on the Record Date will be made available at the Corporate Secretary’s office at 6420 Levit Green Boulevard, Suite 310, Houston, Texas 77021, for ten days before the Annual Meeting.

What is the Record Date and what does it mean?

The Record Date for the Annual Meeting is March 18, 2026. The Record Date is established by our Board as required by Delaware General Corporation Law. Owners of our Common Stock at the close of business on the Record Date are entitled to receive notice of the meeting and to vote at the Annual Meeting and any adjournment, continuation or postponement of the Annual Meeting.

How can I change my vote or revoke my proxy after submitting a proxy?

If you are a stockholder of record, you may revoke or change your vote or revoke your proxy at any time before the final vote at the Annual Meeting in any one of the following ways:

We recommend that you also submit your proxy, voting instructions or vote in advance of the Annual Meeting through the Internet so that your vote will be counted if you later decide not to attend the Annual Meeting

If you are a beneficial owner and your shares are held in “street name” on your behalf by a brokerage firm, bank or other nominee, you should follow the instructions provided by that nominee.

Your most recent proxy card, Internet or telephone proxy is the one that is counted. Your attendance at the Annual Meeting by itself will not revoke your proxy unless you give written notice of revocation to the Corporate Secretary before your proxy is voted or you vote electronically at the Annual Meeting.

What are my voting choices when voting for director nominees and what vote is needed to elect directors?

In voting on the election of director nominees to serve until the 2027 Annual Meeting of Stockholders, stockholders may vote in favor of each nominee or may withhold votes as to each nominee. In addition, if any other candidates are properly nominated at the Annual Meeting, stockholders of record who attend the Annual Meeting could vote for the other candidates. Directors are elected by a plurality vote, which means that the six (6) nominees receiving the most affirmative votes will be elected. Stockholders are not entitled to cumulative voting rights with respect to the election of directors. Only votes “FOR” will affect the outcome.

What are my voting choices when voting to ratify the appointment of our independent registered public accounting firm, and what vote is needed to ratify the appointment?

In voting on the ratification of the appointment of our independent registered public accounting firm, stockholders may vote in favor of or against the ratification, or may abstain from voting on the ratification. The affirmative vote of a majority of the Common Stock having voting power present at the meeting or represented by proxy at the Annual Meeting is required to approve this proposal. Abstentions will be counted as present for purposes of determining a quorum and are considered shares present and entitled to vote and thus will have the effect of a vote “AGAINST” this proposal. We do not expect any broker non-votes in connection with this proposal since we expect brokers to have discretionary authority to vote on this proposal.

This vote is advisory, and therefore not binding on the Board. Although the vote is non-binding, the Board will review the voting results, seek to determine the cause or causes of any significant negative voting, and take them into consideration when making decisions regarding our independent registered public accounting firm for this fiscal year and future fiscal years.

What are my voting choices when voting to approve, on an advisory basis, the compensation of the Company’s named executive officers?

In voting on the approval, on an advisory basis, of the compensation of our named executive officers, stockholders may vote in favor of or against the proposal, or may abstain from voting on this proposal. The affirmative vote of a majority of the Common Stock having voting power present at the Annual Meeting or represented by proxy at the Annual Meeting is required to approve this proposal. Abstentions will be counted as present for purposes of determining a quorum and are considered shares present and entitled to vote and thus will have the effect of a vote “AGAINST” this proposal.

This vote is advisory, and therefore not binding on the Board. Although the vote is non-binding, the Board will review the voting results, seek to determine the cause or causes of any significant negative voting, and take them into consideration when making future decisions regarding executive compensation programs.

What are my voting choices when voting to approve the sixth amendment and restatement of the Plus Therapeutics, Inc. 2020 Stock Incentive Plan?

In voting on the approval of the sixth amendment and restatement of the Plus Therapeutics, Inc. 2020 Stock Incentive Plan, stockholders may vote in favor of or against the proposal, or they may abstain from voting on the proposal. The affirmative vote of a majority of the Common Stock having voting power present at the Annual Meeting or represented by proxy at the Annual Meeting is required to approve this proposal. Abstentions will be counted as present for purposes of determining a quorum and are considered shares present and entitled to vote and thus will have the effect of a vote “AGAINST” this proposal.

How will a proxy get voted?

If you are a stockholder of record and do not vote through the Internet, by completing a proxy card, by telephone or online during the Annual Meeting, your shares will not be voted.

If you properly complete and return a proxy card or vote by Internet or by telephone, the designated proxy holders will vote your shares as you have directed. If you sign a proxy card but do not make specific choices or if you vote by Internet or telephone but do not make specific choices, the designated proxy holders will vote your shares as recommended by the Board as follows:

With respect to the election of directors, if any nominee is unable or declines to serve, or for good cause will not serve, as a director at the time of the Annual Meeting, an event that is not currently anticipated, the designated proxy holders will have the express discretionary authority to vote for a replacement nominee designated by our Board, and proxies will be voted for any nominee designated by our Board to fill the vacancy.

If I am a beneficial owner of shares held in “street name” and I do not provide my brokerage firm, bank or other nominee with voting instructions, what happens?

If you are a beneficial owner and do not instruct your brokerage firm, bank or other nominee how to vote your shares, your shares will be considered “uninstructed” and the question of whether your nominee will still be able to vote your shares depends on whether, pursuant to stock exchange rules, the particular proposal is deemed to be a “routine” matter. Brokerage firms, banks and other nominees can use their discretion to vote “uninstructed” shares with respect to matters that are considered to be “routine,” but not with respect to “non-routine” matters. Under applicable rules and interpretations, “non-routine” matters are matters that may substantially affect the rights or privileges of stockholders, such as elections of directors (even if not contested), mergers, stockholder proposals, executive compensation and certain corporate governance proposals, even if management-supported. Accordingly, your brokerage firm, bank or other nominee may vote your shares on Proposal 2, which is considered “routine,” without your instructions. Your brokerage firm, bank or other nominee may not, however, vote your shares on Proposal 1, Proposal 3, or Proposal 4, without your instructions, because they are considered “non-routine,” which would result in a “broker non-vote” and your shares would not be counted as having been voted on these proposals. Please instruct your brokerage firm, bank or other nominee as to how to vote your shares to ensure that your vote will be counted.

If you are a beneficial owner of shares held in street name, and you do not plan to attend the Annual Meeting, in order to ensure your shares are voted in the way you would prefer, you must provide voting instructions to your brokerage firm, bank or other nominee by the deadline provided in the materials you receive from your nominee.

What are “broker non-votes”?

As discussed above, when a beneficial owner of shares held in “street name” does not give instructions to the brokerage firm, bank or other nominee holding the shares as to how to vote on matters deemed to be “non-routine,” the brokerage firm, bank or other nominee cannot vote the shares. These unvoted shares are counted as “broker non-votes.”

How are abstentions and broker non-votes counted?

Abstentions and broker non-votes will be counted as present for purposes of determining a quorum. An abstention occurs when a stockholder chooses to “ABSTAIN” from voting on a matter. As discussed above, a broker non-vote occurs when a broker, bank, or other stockholder of record, in nominee name or otherwise, exercising fiduciary powers, submits a proxy for the Annual Meeting, but does not vote on a particular proposal because that holder does not have discretionary voting power with respect to that proposal and has not received voting instructions from the beneficial owner. Under the rules that govern brokers who are voting with respect to shares held in street name, brokers have the discretion to vote those shares on routine matters, but not on non-routine matters. We expect the proposal regarding ratification of our auditor to be a routine matter, and therefore, broker non-votes are not expected to exist with respect to such proposal. We expect the other proposals described in this proxy statement to be non-routine. Brokers and nominees do not have discretionary voting power over these non-routine proposals and, therefore, broker non-votes may exist with respect to these proposals. Broker non-votes will not affect the outcome of any of these non-routine matters that are being voted on at the Annual Meeting, provided that a quorum is obtained. However, we strongly encourage you to submit your proxy and exercise your right to vote as a stockholder to ensure your shares are voted in the manner in which you want them voted.

Who pays for the solicitation of proxies?

We will pay the entire cost of the solicitation of proxies for the Annual Meeting. This includes preparation, assembly, printing and mailing of the Notice, this Proxy Statement and any other information we send to stockholders. In addition, we may supplement our efforts to solicit your proxy in the following ways:

We will not pay directors, officers or other regular employees any additional compensation for their efforts to supplement our proxy solicitation. We anticipate banks, brokerage houses and other custodians, nominees and fiduciaries will forward solicitation material to the beneficial owners of shares of Common Stock entitled to vote at the Annual Meeting and that we will reimburse those persons for their out-of-pocket expenses incurred in performing such services.

What constitutes a quorum?

For business to be conducted at the Annual Meeting, a quorum of stockholders must be present. A quorum exists when the holders of at least 331⁄3% of the shares of our Common Stock issued, outstanding and entitled to vote are represented at the Annual Meeting.

On March 18, 2026, there were 171,550,698 shares of our Common Stock outstanding and entitled to one vote. Holders of our Common Stock as of the close of business on the Record Date will be entitled to vote at the Annual Meeting. Thus, based on the holders as of March 18, 2026, we estimate that the holders of approximately 57,183,566 shares of Common Stock would need to be present in person or represented by proxy at the Annual Meeting to have a quorum.

Your shares will be counted as present only if you submit a valid proxy (or one is submitted on your behalf by your brokerage, bank or other nominee), vote by telephone, through the Internet or if you vote online during the Annual Meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, the chairperson of the Annual Meeting or holders of a majority of the voting power of the shares present at the Annual Meeting may adjourn the Annual Meeting to another date.

How many votes may I cast? How many shares are eligible to be voted?

You may cast one vote for every share of our Common Stock that you owned on the Record Date. As of the Record Date, March 18, 2026, there were 171,550,698 shares of Common Stock outstanding, each of which is entitled to one vote.

How will voting on any “other business” be conducted?

Although we do not know of any business to be considered at the Annual Meeting other than the proposals described in this Proxy Statement, if any additional business is presented at the Annual Meeting, your proxy gives authority to the designated proxy holders to vote on such matters according to their best judgment.

Can I vote my shares by filling out and returning the Notice?

No. The Notice identifies the items to be voted on at the Annual Meeting, but you cannot vote by marking the Notice and returning it. The Notice provides instructions on how to vote by proxy in advance of the Annual Meeting through the Internet, by telephone, using a printed proxy card or online during the Annual Meeting.

Where can I find the voting results of the Annual Meeting?

We will publish the final voting results in a current report on Form 8-K, which we expect to file with the SEC within four business days of the Annual Meeting. If the final voting results are unavailable in time to file a current report on Form 8-K with the SEC within four business days after the Annual Meeting, we intend to file a Form 8-K to disclose the preliminary results and, within four business days after the final results are known, we will file an additional current report on Form 8-K with the SEC to disclose the final voting results.

Does the Company have a policy about directors’ attendance at the Annual Meeting?

The Company does not have a policy about directors’ attendance at the Annual Meeting, but directors are encouraged to attend. All directors and director nominees at the time other than Kyle Guse and Richard Hawkins attended the 2025 Annual Meeting of Stockholders.

Could any additional proposals be raised at the Annual Meeting?

We are not aware of any items, other than those referred to in the accompanying Notice, which may properly come before the meeting or other matters incident to the conduct of the meeting. As to any other item or proposal that may properly come before the meeting, it is intended that proxies will be voted in the discretion of the proxy holders.

How can I view or request copies of the Company’s corporate documents and SEC filings, including the Annual Report?

The Company’s website contains, among other corporate governance documents, the Company’s Corporate Governance Guidelines and Codes of Business Conduct & Ethics. To view these documents, go to www.plustherapeutics.com, click “For Investors” then “Governance” and then “Corporate Governance Materials.” To view the Company’s committee charters, go to www.plustherapeutics.com, click “For Investors” then “Governance” and then “Board Committees.” To view the Company’s SEC filings, including Forms 3, 4 and 5 filed by the Company’s directors and executive officers, go to www.plustherapeutics.com, click on “For Investors” then “Reports & Filings.” The 2025 Annual Report includes our consolidated financial statements for the year ended December 31, 2025. We have furnished the 2025 Annual Report to all stockholders.

CORPORATE GOVERNANCE

Director Candidates

The names of the members of the Board and Plus’s director nominees, their respective ages, their positions with Plus and other biographical information as of March 31, 2026, are set forth below. Except for Marc H. Hedrick, M.D., our Chief Executive Officer, President and a director, there are no other family relationships among any of our directors or executive officers.

Criteria for Board Membership

In addition to the qualifications, qualities and skills that are necessary to meet U.S. state and federal legal, regulatory and Nasdaq Stock Market, LLC (“Nasdaq”) listing requirements and the provisions of our Certificate of Incorporation, as amended (the “Certificate of Incorporation”), amended and restated Bylaws (the “Bylaws”), corporate governance guidelines (the “Corporate Governance Guidelines” and charters of our Board’s committees, our Board will consider appropriate factors in evaluating director nominees, including: character, judgment, leadership, business acumen, diversity of background and perspective, skills, age, gender, ethnicity, professional experience, knowledge of or experience in the pharmaceutical industry, sufficient time to devote to Plus’s affairs and commitment to represent the long-term interests of Plus’s stockholders.

Although we do not have a formal diversity policy, our Board does consider gender and ethnic diversity as factors in its evaluation of candidates for director nominations. There are no other pre-established qualifications, qualities or skills at this time that any particular director nominee must possess and nominees are not discriminated against on the basis of race, religion, national origin, sexual orientation, disability or any other basis proscribed by law. The Nominating and Corporate Governance Committee does not assign specific weights to any particular criteria, nor has it adopted specific requirements. Rather, the Board believes that the backgrounds and qualifications of the directors, considered as a group, should provide a composite mix of experience, knowledge and abilities that will allow the Board to fulfill its responsibilities. The goal of the Nominating and Corporate Governance Committee is to assemble a Board that brings a variety of skills derived from high quality businesses and professional experience.

Our Board is composed of a diverse group of professionals in their respective fields. Many of the current directors have or have held senior leadership experience at major domestic and international companies. In these positions, they have also gained experience in core management skills, such as strategic and financial planning, public company financial reporting, compliance, risk management, leadership development, and international business experience. Most of our directors also have experience serving on boards of directors and board committees of other public companies in the pharmaceutical industry, and have an understanding of corporate governance practices and trends, different business processes, challenges, and strategies. Further, our directors also have other experience that makes them valuable members, such as medical knowledge and research experience, which provides insight into strategic and operational issues faced by us.

The Nominating and Corporate Governance Committee and the Board believe that the above-mentioned attributes, along with the leadership skills and other experiences of our Board members described below, provide us with a diverse range of perspectives and judgment necessary to guide our strategies and monitor their execution.

Set forth below is biographical information for the director nominees. This includes information regarding each director’s experience, qualifications, attributes or key skills that led our Board to recommend them for service on our Board.

Biographical Information About Our Director Nominees

Richard J. Hawkins. Mr. Hawkins has served on our Board since December 2007 and has been the Chairman of our Board since January 2018. In 1982, Mr. Hawkins founded Pharmaco, a clinical research organization, where he served as its Chairman, President and Chief Executive Officer until 1991 when it merged with the predecessor of PPD-Pharmaco. In 1992, Mr. Hawkins co-founded Sensus Drug Development Corporation, a privately-held company focused on the development of drugs to treat endocrine disorders, which developed and received regulatory approval for SOMAVERT, a growth hormone antagonist approved for the treatment of acromegaly, which is now marketed by Pfizer, Inc. (NYSE:PFE), where he served as Chairman until 2000. In 1994, Mr. Hawkins co-founded Corning Biopro, a contract protein manufacturing firm, where he served on its board until Corning BioPro’s sale to Akzo-Nobel, N.V. (OTC:AKZOY), a publicly-held producer of paints, coatings and specialty chemicals, in 2000. In September 2003, Mr.

Hawkins founded LabNow, Inc., a privately held company that develops lab-on-a-chip sensor technology, where he served as the Chairman and Chief Executive Officer until October 2009. In February 2011, Mr. Hawkins became Chief Executive Officer, and held the positions of Chief Executive Officer, President and Chairman of Lumos Pharma, Inc. (Nasdaq: LUMO) until the time of its sale in December 2023. Additionally, Mr. Hawkins served on the board of SciClone Pharmaceuticals, Inc. (HKD: SCLN), a publicly-held specialty pharmaceutical company, from October 2004 through December 2017. He also served on the Presidential Advisory Committee for the Center for Nano and Molecular Science and Technology at the University of Texas at Austin, and was inducted into the Hall of Honor for the College of Natural Sciences at the University of Texas. Mr. Hawkins is a member of the National Ernst & Young Entrepreneur of the Year Hall of Fame. Mr. Hawkins graduated cum laude with a B.S. in Biology from Ohio University, where he later received the Ohio University Konneker Medal, the highest award given to a faculty member or former student, for entrepreneurial excellence. We believe Mr. Hawkins’s qualifications to serve on our Board include his executive experience working with life sciences companies, his extensive experience in pharmaceutical research and development, his knowledge, understanding and experience in the regulatory development and approval process, and his service on other public company boards and committees.

Marc H. Hedrick, M.D. Dr. Hedrick joined the Company in October 2002 as its Chief Scientific Officer. In May 2004, he was appointed as President of the Company and in April 2014, he was appointed as its Chief Executive Officer. Dr. Hedrick has served as a member of our board of directors (the “Board”) since joining the Company in October 2002. Previously, Dr. Hedrick served in a number of executive leadership positions, including President and Chief Executive Officer of StemSource from 2001 to 2003 and Chief Scientific Officer and Medical Director of Macropore Biosurgery from 2002 to 2004. Dr. Hedrick has also served as a board member for a number of public and private companies since 2000. Prior to his corporate career, Dr. Hedrick was Associate Professor of Surgery and Pediatrics at the University of California, Los Angeles (“UCLA”). While at UCLA, Dr. Hedrick’s academic research received both National Institutes of Health funding as well as private and public capitalization and was widely acknowledged through scientific publications and the media. Dr. Hedrick also has first-hand experience as a physician, practicing general, vascular and craniofacial surgery. Dr. Hedrick has a medical degree from The University of Texas Southwestern Medical School and a Master of Business Administration from the UCLA Anderson School of Management and is a trained general, vascular and plastic surgeon. We believe Dr. Hedrick’s qualifications to serve on our Board include his executive, financial, governance and operational leadership experience in medical and pharmaceutical product development.

Howard Clowes. Mr. Clowes has served on our Board since April 1, 2020. From January 2005 until he retired as a lawyer in December 2018, Mr. Clowes was a partner in the law firm DLA Piper (US) LLC. From 1982 until the formation of DLA Piper in 2005, he was an associate and then a partner in the predecessor firms of DLA Piper, holding various management positions, including serving on its board of directors and its compensation committee. Mr. Clowes served on the board of Equalize Health and as chair of its governance committee from January 2018 to May 2022, and served on the board of AFRAC from May 2021 to December 2024, each of which are nonprofit corporations focused on global healthcare. Mr. Clowes served on the board of the Law Foundation of Silicon Valley, a non-profit organization located in San Jose, California, that provides free legal services to Silicon Valley residents in need, from 2008 until December 2018, during which he served in various positions, including President of its board of directors, and Chair of its Strategic Planning and Chief Executive Officer Search Committee. From 2017 to 2021, Mr. Clowes served as a Lecturer at the University of California, Berkeley School of Law, teaching a course in International Business Negotiations. Mr. Clowes earned his J.D. at U.C. Berkeley, his B.A. in Experimental Psychology at U.C. Santa Barbara, and in 2023, Mr. Clowes received his National Association of Corporate Directors Directorship Certification. We believe Mr. Clowes’ qualifications to serve on the Board include his extensive experience as a lawyer, advising boards of directors and their audit, compensation and corporate governance committees on a wide range of matters, his experience with a wide range of transactions and his experience serving on various boards of directors.

Ronald A. Andrews. Mr. Andrews was appointed to our Board in March 2026. Mr. Andrews is currently serving as Founder, Managing Partner of The Bethesda Group, which is a strategic consulting firm focused on helping organizations in the molecular diagnostic/genomic market segments with strategy, commercial execution, C-suite mentorship and fractional C suite support. From April 2023 to July 2024, Mr. Andrews served as President and CEO of Twin Strand Biosciences and from July 2016 to December 2022 as President and CEO of Oncocyte Inc. (NASDAQ: OCX). From July 2015 to July 2019 he worked as Founder and Senior Partner of The Bethesda Group and from September 2013 to February 2015 he was President, Genetic Sciences Division, at Thermo Fisher Scientific/ Life Technologies (NASDAQ:TMO). Mr. Andrews is an experienced leader in the diagnostics and molecular diagnostics industry with over 35 years leading various sized organizations from divisions of large global entities to public CEO roles in successful start-up organizations. Since September 2023, Mr. Andrews has been on the board of directors at DxCover Inc., where he serves as Executive Chairman, on the board of directors of Agendia, Inc. since July 2023, and on the board of directors of Precipio Inc. since March 2021. Mr. Andrews has also served on the boards of AliveDx Suisse SA (March 2023 to November 2025), SimBioSys (October 2022 to September 2024), ASCO CancerLinq, Board of Governors (June 2015 to December 2023), Oxford Immunotec (August 2015 to March 2021), Insight Genetics (June 2015 to May 2019), Orion Healthcare (September 2016 to July 2018) and the Advisory Board of Safeguard Scientific Inc. (September 2008 to January 2016). He currently serves on the Board of Trustees for Wofford College. Mr. Andrews graduated from Wofford College in 1981 with degrees in Biology and Chemistry. We believe Mr. Andrews’ qualifications to serve on the Board include his extensive experience in diagnostics and molecular diagnostics and his experience leading various sized organizations and serving on various boards of directors.

Kyle Guse, Esq., MBA, CPA (inactive). Mr. Guse was appointed to our Board in April 2025. Mr. Guse served as the Chief Legal Officer of DDC Enterprise Ltd. (NYSE:DDC), an NYSE-American-listed international consumer foods company, from September

2023 to August 2025. From January 2013 to May 2023, Mr. Guse was Chief Financial Officer, General Counsel and Secretary of Atossa Therapeutics, Inc. (Nasdaq, ATOS), a Nasdaq-listed biotechnology company developing treatments and prevention for breast cancer. Mr. Guse’s experience includes 30 years of counseling innovative, rapid growth companies through all aspects of finance, corporate governance, securities laws and commercialization, with a particular focus on M&A and capital market transactions. Mr. Guse has practiced law at several of the largest international law firms, including from January 2012 through January 2013 as a partner at Baker Botts LLP and, prior to that, from October 2007 to January 2012, as a partner at McDermott Will & Emery LLP. Before working at McDermott Will & Emery, Mr. Guse served as a partner at Heller Ehrman LLP. Mr. Guse began his career as an accountant at Deloitte and he is an inactive Certified Public Accountant and member of the bars of California and Washington. Mr. Guse earned a B.S. in business administration and an M.B.A. from California State University, Sacramento, and a J.D. from Santa Clara University School of Law. We believe that Mr. Guse’s extensive legal and business expertise in corporate finance and capital markets, corporate governance and mergers and acquisitions qualifies him to serve on our Board.

An van Es-Johansson, M.D. Dr. van Es-Johansson has served on our Board since January 1, 2020. Dr. van Es-Johansson served as the Chief Medical Officer for AlzeCure Pharma, a Swedish pharmaceutical company with a primary focus on Alzheimer’s disease, from September 2018 through March 1, 2021, following which she has continued to serve AlzeCure Pharma as a Senior Advisor beginning in March 2021. Since 2021 she has been a Senior Advisor for Sinfonia AB, a Swedish pharmaceutical company with focus on neuroscience. From May 2005 to September 2018, Dr. van Es-Johansson served in a range of executive roles of increasing responsibility at Sobi, an international rare disease company headquartered in Stockholm, Sweden, including as Vice President and Head of EMENAR Medical Affairs for Specialty Care and Partner Products from March 2013 to January 2018. Prior to her time at Sobi, Dr. van Es-Johansson served in leadership positions within large pharmaceutical and smaller biotechnology companies, including Roche, Pharmacia, Eli Lilly, Active Biotech and BioStratum. From 2004 to 2016, she was a member of the Scientific Advisory Board of Uppsala Bio and currently serves on the board of directors of Savara, Inc. (Nasdaq: SVRA), Lumos Pharma, Inc. (Nasdaq: LUMO) and privately held Agendia BV. She also served on the board of directors at BioInvent International AB (Nasdaq: OMX Stockholm: BINV), from June 2016 to February 2021; on the board of directors of Alzecure AB (NASDAQ OMX Stockholm: ALZCUR), from 2017-2020; on the board of directors of Medivir AB (Nasdaq OMX Stockholm: MVIR) from 2019-2022; and on the board of directors of IRLAB AB (Nasdaq OMX Stockholm: IRLAB) from May 2022 to February 2023. Dr. van Es-Johansson received a M.D. from Erasmus University, Rotterdam, The Netherlands. We believe Dr. van Es- Johansson’s qualifications to serve on our Board include her extensive medical knowledge and experience in the pharmaceutical industry.

Term of Office

Our directors are elected for a term of one (1) year and until their respective successors are elected and qualified, or until their earlier resignation, disqualification, or removal.

Family Relationships

There are no family relationships among any of the directors or executive officers.

Independence of Directors

Our Common Stock is listed on the Nasdaq Capital Market and under the listing rules of Nasdaq, subject to specified exceptions, independent directors must comprise a majority of a listed company’s board of directors, and each member of a listed company’s audit, compensation and nominating and corporate governance committees must be independent. Under Nasdaq listing rules, a director will only qualify as an “independent director” if, among other things, the listed company’s board of directors affirmatively determines that the director does not have a relationship which, in the opinion of the listed company’s board of directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director.

Our Board reviews the independence of each director. This review is based primarily on responses of the directors to questions in a directors’ and officers’ questionnaire regarding employment, business, familial, compensation and other relationships with Plus and our management. Our Board has determined that no transactions or relationships existed that would disqualify any of our directors under the Nasdaq rules or would require disclosure under SEC rules, with the exception of Marc H. Hedrick, M.D., our President and Chief Executive Officer, because of his current employment relationship with Plus. In making these determinations, our Board considered the current and prior relationships that each non-employee director has with us and all other facts and circumstances our Board deemed relevant in determining their independence, including the beneficial ownership of our securities by each non-employee director and the transactions described in the section titled “Certain Relationships and Related Transactions.”

Board Leadership

We currently separate the roles of Chief Executive Officer and Chairman of the Board. Our President and Chief Executive Officer is responsible for setting the strategic direction for our company and the day-to-day leadership and performance of our Company, while the Chairman of our Board presides over meetings of the Board, including executive sessions of the Board. Separating the duties of

the Chairman from the duties of the Chief Executive Officer allows our Chief Executive Officer to focus on our day-to-day business, while allowing the Chairman to lead the Board in its fundamental role of providing advice to and independent oversight of management. Specifically, our Chairman runs meetings of our independent directors and assists with other corporate governance matters. Our Board believes that this structure ensures a greater role for the independent directors in the oversight of our company and active participation of the independent directors in setting agendas and establishing priorities and procedures for the work of our Board. Our Board believes that we have an appropriate leadership structure for us at this time which demonstrates our commitment to good corporate governance. Although the roles of Chairman and Chief Executive Officer are currently separate, our Nominating and Corporate Governance Committee and Board believe it is appropriate for our Chief Executive Officer to serve as a member of our Board.

Role of the Board in Risk Oversight

Risk is inherent with every business and how well a business manages risk can ultimately determine its success. We face a number of risks, including those described under “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2025, and in our other filings with the SEC.

Our Board is actively involved in oversight of the key risks that could affect us. Our Board oversees our risk management processes directly and through its committees. Our management is responsible for risk management on a day-to-day basis and our Board of directors and its committees oversee the risk management activities of management. Our Board believes that risk management is an important part of establishing, updating and executing on Plus’s business strategy. Our Board, as a whole and at the committee level, has oversight responsibility relating to risks that could affect our corporate strategy, business objectives, compliance, operations, financial condition and performance. Our Board focuses its oversight on the most significant risks facing our company and oversees our risk management processes to identify, prioritize, assess, manage and mitigate those risks, which in turn supports the achievement of organizational objectives, improves long-term organizational performance and enhances stockholder value, while mitigating and managing identified risks. A fundamental part of our approach to risk management is not only understanding the most significant risks we face as a company and the necessary steps to manage those risks, but also deciding what level of risk is appropriate for our company. Our Board plays an integral role in guiding management’s risk tolerance and determining an appropriate level of risk. In addition, members of our senior management team attend our quarterly board meetings and are available to address any questions or concerns raised by the board on risk management and any other matters. Our Board believes that full and open communication between management and the Board is essential for effective risk management and oversight.

While our full Board has overall responsibility for evaluating key business risks, our committees monitor and report to our Board on certain risks. The Compensation Committee is responsible for overseeing the management of risks relating to our human capital and executive compensation plans and arrangements. The Audit Committee is responsible for overseeing the management of risks relating to accounting matters, financial reporting, and cybersecurity. The Nominating and Corporate Governance Committee is responsible for overseeing the management of risks associated with the independence of our Board and potential conflicts of interest. Although each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire Board is regularly informed about the primary risks associated with our business, as well as the key risk areas monitored by its committees. We believe that our Board’s leadership structure supports effective risk management because it allows independent directors at the board level and on our committees to exercise oversight over management.

Our Board is committed to effective corporate governance and has adopted a wide range of practices and procedures that promote effective Board oversight. For example:

Composition of Our Board

Our Board may establish the authorized number of directors from time to time by resolution. Our Board currently consists of six (6) members.

No stockholder has any special rights regarding the election or designation of members of our Board. There is no contractual arrangement by which any of our directors are appointed to our Board. Our current directors will continue to serve as directors until the Annual Meeting and until their successor is duly elected, or if sooner, until their earlier death, resignation or removal.

Our Board held seven (7) meetings during 2025. No member of our Board attended fewer than seventy-five percent (75%) of the aggregate of (a) the total number of meetings of the Board (held during the period for which he or she was a director) and (b) the total number of meetings held by all committees of the Board on which such director served (held during the period that such director served). Members of our Board are invited and encouraged to attend our annual meeting of stockholders. In 2025, all members of our Board at the time attended the 2025 Annual Meeting of Stockholders other than Kyle Guse and Richard Hawkins.

Executive Sessions of Independent Directors

In order to promote open discussion among non-management directors, and as required under applicable Nasdaq rules, our Board conducts executive sessions of non-management directors during each regularly scheduled Board meeting and at such other times, if requested by a non-management director. In 2025, the non-management directors met in executive session four (4) times. The non-management directors provide feedback to executive management, as needed, promptly after the executive session. Dr. Hedrick does not participate in such sessions. As Chairman of our Board, Mr. Hawkins presides over meetings of our independent directors without management present.

Committees of Our Board

Our Board has established three standing committees: an Audit Committee; a Compensation Committee; and a Nominating and Corporate Governance Committee. The composition and responsibilities of each of these committees of our Board are described below. Members serve on these committees until their resignation or until otherwise determined by our Board. Our Board may establish other committees as it deems necessary or appropriate from time to time. The composition and functioning of all of our committees comply with all applicable requirements of the Sarbanes-Oxley Act, Nasdaq and SEC rules and regulations.

Each committee has adopted a written charter, which Board committees’ charters are available on our website at https://ir.plustherapeutics.com/governance/board-committees. The following table provides membership and meeting information for the fiscal year ended December 31, 2025 for each of the committees of our Board. Each Board member attended 75% or more of the aggregate number of meetings of the standing committee on which she or he served, held during the last fiscal year for which she or he was a committee member.

The Board has determined that each member of each standing committee meets the applicable Nasdaq rules and regulations regarding “independence” and each member is free of any relationship that would impair his or her individual exercise of independent judgment with regard to the Company. Each Board member attended 75% or more of the aggregate number of meetings of the standing committee on which she or he served, held during the last fiscal year for which she or he was a committee member.

Below is a description of each committee of our Board.

Audit Committee

Our Audit Committee currently consists of Mr. Clowes, Dr. van Es-Johansson and Mr. Guse, who serves as Chairperson of the Audit Committee. The Board has determined that all members of the Audit Committee satisfied the independence requirements under Nasdaq listing standards and Rule 10A-3(b)(1) of the Exchange Act. The Board has determined that Mr. Guse is an “audit committee financial expert” within the meaning of SEC regulations. Each member of our Audit Committee can read and understand fundamental financial statements in accordance with applicable requirements. In arriving at these determinations, the Board has examined each Audit Committee member’s scope of experience and the nature of their employment. No member of the Audit Committee simultaneously serves on the audit committees of more than three (3) public companies, and no member of our Audit Committee has participated in the preparation of the financial statements of Plus at any time during the past three (3) years.

The primary purpose of the audit committee is to discharge the responsibilities of our Board with respect to our corporate accounting and financial reporting processes, systems of internal control and financial-statement audits, and to oversee our independent registered accounting firm. Specific responsibilities of our Audit Committee as provided in the Audit Committee Charter include:

Compensation Committee

Our Compensation Committee currently consists of Mr. Guse, Mr. Clowes and Dr. van Es-Johansson, who serves as the committee’s Chairperson. Our Board has determined that Dr. van Es-Johansson, Mr. Guse and Mr. Clowes are independent under Nasdaq listing standards and are “non-employee directors” as defined in Rule 16b-3 promulgated under the Exchange Act.

The primary duties and responsibilities of our Compensation Committee as provided in the Compensation Committee Charter include, among other things, overseeing our compensation policies, plans and programs and determine the compensation to be paid to our executive officers, directors and other senior management, as appropriate.

Specific responsibilities of our Compensation Committee include:

See the sections titled “Executive Compensation” and “Director Compensation” for a description of our processes and procedures for the consideration and determination of our executive officers and directors compensation.

Nominating and Corporate Governance Committee

Our Nominating and Corporate Governance Committee currently consists of Mr. Clowes, Dr. van Es-Johansson and Ronald A. Andrews, each of whom our Board has determined is independent under the Nasdaq listing standards, a non-employee director and free from any relationship that would interfere with the exercise of his or her independent judgment. The Chairperson of our Nominating and Corporate Governance Committee is Mr. Clowes.

Specific responsibilities of our Nominating and Corporate Governance Committee as provided in the Nominating and Corporate Governance Committee Charter include, among others:

Stockholder Communications with the Board

Stockholders may contact an individual director, the Board as a group, or a specified Board committee or group, including the independent directors as a group, by the following means:

Each communication should specify the applicable addressee or addressees to be contacted as well as the general topic of the communication. The Chairman of the Board will initially receive and process communications before forwarding them to the addressee. Communications also may be referred to other departments within the Company. The Chairman of the Board generally will not forward to the directors a communication that he determines to be primarily commercial in nature or related to an improper or irrelevant topic, or that requests general information about us.

Code of Business Conduct and Ethics

We have adopted a Code of Business Conduct and Ethics that applies to all our directors, officers and employees, including our principal executive officer, principal financial officer and principal accounting officer. This Code of Business Conduct and Ethics has been posted on our website at www.plustherapeutics.com. To the extent required by SEC rules, we intend to post amendments to this code, or any waivers of its requirements, on our website at https://ir.plustherapeutics.com/governance/corporate-governance-materials. To date, there have been no waivers under our Code of Business Conduct and Ethics.

Anti-Hedging and Anti-Pledging Policy

Under our Insider Trading and Communications Policy, our directors, officers, employees, consultants and contractors (and each such individual’s family members, other members of a person’s household and entities controlled by a person covered by this policy, as described in the policy) are prohibited from engaging in the following transactions at any time: (i) engaging in short sales of our securities; (ii) trading in put options, call options or other derivative securities involving our securities on an exchange or in any other organized market; (iii) engaging in hedging or monetization transactions involving our securities, including through the use of financial instruments such as prepaid variable forwards, equity swaps, collars and exchange funds; and (iv) holding our securities in a margin account or otherwise pledging our securities as collateral for loan.

Corporate Governance Guidelines

The Board has adopted Corporate Governance Guidelines, which addresses matters such as the Board’s core responsibilities and duties and the Board’s composition and compensation. The guidelines are also intended to align the interests of directors and management with those of our stockholders. The Corporate Governance Guidelines are available on our website at https://ir.plustherapeutics.com/governance/corporate-governance-materials.

Clawback Policy

Our Board has adopted the Plus Therapeutics, Inc. Incentive Compensation Recovery Plan, a policy for recovery of erroneously awarded compensation (the “Clawback Policy”), in accordance with the Nasdaq listing standards and Rule 10D-1 under the Exchange Act, which applies to our current and former executive officers. Under the Clawback Policy, we are required to recoup the amount of any erroneously awarded compensation on a pre-tax basis, within a specified lookback period, in the event of any Accounting Restatement (as defined in the Clawback Policy), subject to limited impracticability exceptions. Covered restatements include both a restatement to correct an error that is material to previously issued financial statements or that would result in a material misstatement if the error were corrected in the current period or left uncorrected in the current period. The amount required to be recovered is the excess of the amount of incentive-based compensation received over the amount that otherwise would have been received had it been determined based on the restated financial measure. The Clawback Policy is overseen and administered by the Compensation Committee. The full text of the Clawback Policy was included as Exhibit 97.1 to our 2023 Annual Report, filed with the SEC on March 5, 2024.

Delinquent Section 16(a) Reports

Section 16(a) of the Exchange Act requires our executive officers and directors to file initial reports of ownership and reports of changes in ownership with the SEC and to furnish us with copies of all Section 16(a) forms they file.

Based solely on our review of the copies of such reports filed with the SEC and written representations from the reporting person that no other reports were required during the fiscal year ended December 31, 2025, all Section 16(a) filing requirements during that fiscal year were met.

EXECUTIVE OFFICERS

The following table sets forth information for our executive officers as of the date of this Proxy Statement:

Biographical information for Marc H. Hedrick, M.D. is included above with the director biographies in the section titled “Biographical Information About Our Director Nominees.”

Andrew Sims. Mr. Sims joined us as Chief Financial Officer in February 2020. Prior to his appointment as our Chief Financial Officer, Mr. Sims held roles at several private equity-backed companies. Between 2012 and 2017, Mr. Sims was Chief Financial Officer of Amplify LLC, an advisory and management consulting services firm. Following his time at Amplify, Mr. Sims served as Chief Financial Officer of Verbatim Support Services LLC, a litigation support company, from 2017 to 2019. His focus has been on mergers and acquisitions, integrations, corporate capitalization and building out and managing teams to support global growth. Previously, Mr. Sims was Partner at Mazars, a global accounting, advisory, audit, tax and consulting firm. Working from both the Oxford, England and New York offices, Mr. Sims audited and advised global public clients, including a variety of healthcare companies, with average annual revenues in excess of $1 billion. Further, he was the lead partner on over fifty (50) acquisitions ranging from $5 million to $4 billion in purchase price. He is a Certified Public Accountant in the U.S. and a Chartered Accountant in England and Wales. Mr. Sims is a graduate of Buckingham University in the United Kingdom.

EXECUTIVE COMPENSATION

Executive Officer Compensation

Summary Compensation Table

The following table provides information for the compensation awarded to or earned by our Chief Executive Officer and our two other most highly compensated executive officers for fiscal years 2025 and 2024, or collectively, the named executive officers (the “NEOs”):

Narrative Disclosure to Summary Compensation Table

Employment Agreements

On May 13, 2020 we entered into Amended and Restated Executive Employment Agreements with each of Dr. Hedrick (the “Hedrick Employment Agreement”) and Mr. Sims (the “Sims Employment Agreement” and, together with the Hedrick Employment Agreement, the “Executive Employment Agreements”). The Executive Employment Agreements generally provide for a minimum base salary, a discretionary annual cash bonus based on the achievement of Company performance goals and the ability to participate in, subject to applicable eligibility requirements, all of our benefit plans and fringe benefits and programs that may be provided to our executives from time to time. Dr. Hedrick is also eligible for certain severance payments as described further below under “Potential Payments upon Termination or Change-in-control” below.

Compensation Committee

The Compensation Committee operates in accordance with the compensation committee charter (the “Compensation Committee Charter”). The Compensation Committee Charter outlines responsibilities and duties of the members, sets forth the frequency of meetings, establishes and reviews the overall compensation policies and practices of the Company and also sets forth the process to review and approve the executive compensation program for the Chief Executive Officer and other executive officers, and makes appropriate recommendations to the Board.

The Compensation Committee approves or makes recommendations to our Board on decisions concerning compensation of the executive management team and the Board on a periodic basis to ensure that it is consistent with our short-term and long-term goals. The Compensation Committee assesses the appropriateness of the nature and amount of compensation of our executives by reference to relevant employment market conditions with the overall objective of ensuring maximum stakeholder benefit from the recruitment and retention of a high-quality board and executive team.

Additionally, the Compensation Committee is responsible for evaluating the performance of the Company’s key senior executives. The Company’s Chief Executive Officer and other members of management regularly discuss the Company’s compensation issues with Compensation Committee members. The Compensation Committee reviews and recommends to the Board the overall bonus and equity incentive awards for employees of the Company. Additionally, the Company’s Chief Executive Officer makes recommendations to the Compensation Committee for review, modification (if applicable) and approval in relation to bonuses and equity incentive awards for members of the executive management team.

Compensation Setting Process

In the process of determining compensation for our NEOs, the Compensation Committee considers the current financial position of the Company, the strategic goals of the Company, and the performance of each of our NEOs. The Compensation Committee retained Anderson Pay Advisors in January 2024 and January 2025, to perform an independent compensation review and to provide compensation research, analysis and recommendations. In addition, from time to time, the Compensation Committee considers the various components (described below) of our executive compensation program in relation to compensation paid by other public companies, compensation data from Radford Global Life Sciences Survey, a historical review of all executive officer compensation, and recommendations from our Chief Executive Officer (other than for his own compensation). The Compensation Committee has the sole authority to select, compensate and terminate its external advisors.

The Compensation Committee utilizes the following components of compensation (described further below) to strike an appropriate balance between promoting sustainable and excellent performance and discouraging any excessive risk-taking behavior:

Annual Base Salaries

Our NEOs receive a base salary to compensate them for services rendered to us. The base salary payable to each named executive officer is intended to provide a fixed component of compensation reflecting the executive’s skill set, experience, role and responsibilities. None of the NEOs is currently party to an agreement or arrangement that provides for automatic or scheduled increases in base salary.

Equity-Based Incentive Compensation

We designed our long-term equity grant program to further align the interests of our executives with those of our stockholders, provide our executives with a strong link to our long-term performance and create an ownership culture. Historically, the Compensation Committee has granted stock options, although from time-to-time, to further increase the emphasis on performance-based compensation, the Compensation Committee may grant other equity awards as allowed by the 2020 Stock Incentive Plan, based on its judgment as to whether the complete compensation packages given to our executives, including prior equity awards, are appropriate and sufficient to retain and incentivize the executives and whether the grants balance long-term versus short-term compensation. The Compensation Committee also considers our overall performance as well as the individual performance of each of our NEOs, the potential dilutive effect of restricted stock awards, the dilutive and overhang effect of the equity awards and recommendations from the Chief Executive Officer (other than with respect to his own equity awards).

Stock options are granted with an exercise price equal to the fair market value of our Common Stock on the date of grant.

For the year ended December 31, 2025, our Chief Executive Officer was awarded stock options covering a total of 6,148,995 shares and restricted stock units covering a total of 1,916,168 shares, and our Chief Financial Officer was awarded stock options covering a total of 1,439,656 shares and restricted stock units covering a total of 459,878 shares. For the year ended December 31, 2024, our Chief Executive Officer was awarded stock options covering a total of 291,607 shares, our Chief Financial Officer was awarded stock options covering a total of 65,007 shares and our former Chief Medical Officer was issued a stock option covering 24,073 shares. You can find more information on the stock options granted to our Named Executive Officers below under “Outstanding Equity Awards at December 31, 2025” heading below.

Annual Bonuses and Non-Equity Incentive Plan Compensation

Target bonuses are reviewed annually and established as a percentage of the NEOs’ base salaries, generally based upon seniority of the officer and targeted at or near the median of the peer group and relevant survey data (including the Radford Global Life Sciences Survey). Each year, the Compensation Committee establishes corporate objectives related to the Company’s clinical, financial and operational goals and sets each NEO’s respective bonus target percentages, taking into account recommendations from our Chief Executive Officer as it relates to individual objectives for executive positions other than the Chief Executive Officer. Our Chief Executive Officer’s target bonus is set by the Compensation Committee to align entirely with our overall corporate objectives. Our other NEOs have additional individual goals, the attainment of which comprises a specified percentage of their total bonus compensation. After each fiscal year-end, our Chief Executive Officer provides the Compensation Committee with a written evaluation showing actual performance as compared to corporate and/or individual objectives, and the Compensation Committee uses that information, along with the overall corporate performance, to determine what percentage of each executive’s bonus target will be paid out as a bonus for that year. Overall, the Compensation Committee seeks to establish corporate and individual functional goals to be challenging, yet attainable, and stretch goals to be highly challenging.

Dr. Hedrick’s target bonus for the Company’s 2025 and 2024 fiscal years, as a percentage of base salary, was fifty-five percent (55%). Mr. Sims’ target bonus as a percentage of base salary was forty percent (40%) for the Company’s 2025 and 2024 fiscal years.

For the Company’s 2025 fiscal year, the corporate goals approved by the Board (upon recommendation of the Compensation Committee for purposes of executive compensation) were determined by the Compensation Committee to have been achieved at a level of 95%. As our Chief Executive Officer’s bonus is based exclusively on attainment of our corporate goals, Dr. Hedrick received $305,663, or 95% of his target cash bonus. Based upon the attainment of 95% of the corporate goals, and upon an attainment of ninety-eight percent (98%) of his individual goals, our Chief Financial Officer, Mr. Sims, received $149,175, or 95.6% of his target cash bonus.

For the Company’s 2024 fiscal year, the corporate goals approved by the Board (upon recommendation of the Compensation Committee for purposes of executive compensation) were determined by the Compensation Committee to have been achieved at a level of 105%. As our Chief Executive Officer’s bonus is based exclusively on attainment of our corporate goals, Dr. Hedrick received $321,321, or 105% of his target cash bonus. Based upon the attainment of 105% of the corporate goals, and upon an attainment of 105% of his individual goals, our Chief Financial Officer, Mr. Sims, received $156,555, or 105% of his target cash bonus. Dr. LaFrance left his position of Chief Medical Officer on June 11, 2024 and was not eligible for a bonus in 2024.

Personal Benefits and Perquisites

All of our executives are eligible to participate in our employee benefit plans, including medical, dental, vision, life insurance, short-term and long-term disability insurance, flexible spending accounts and 401(k). These plans are available to all full-time employees. In addition, we pay the taxes related to the vesting of restricted stock units we have issued to our employees, including executive officers. In keeping with our philosophy to provide total compensation that is competitive within our industry, we offer limited personal benefits and perquisites to executive officers. You can find more information on the amounts paid for these perquisites to, or on behalf of, our NEOs in our Summary Compensation Table.

Outstanding Equity Awards at December 31, 2025

The following table sets forth certain information regarding equity awards granted to our NEOs that remain outstanding as of December 31, 2025.

Potential Payments upon Termination or Change-in-control

Pursuant to the terms of the Executive Employment Agreements, if one of our NEOs is terminated without “cause” or resigns for “good reason,” (both, a “Severance Termination”), then such NEO will be eligible to receive: (i) an amount equal to twelve (12) months of his base salary; (ii) an amount equal to his target bonus for the year in which such Severance Termination occurs; (iii) the annual bonus earned for the prior calendar year, if not yet paid, as of the date of such Severance Termination; (iv) an amount equal to twelve (12) months of the premiums such NEO is required to pay under the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”), to continue coverage for him and his eligible dependents under our group health plans; and (v) the accelerated vesting of such NEO’s unvested equity incentive awards that would have vested during the period beginning on the date of such Severance Termination and ending on (a) in case of a Severance Termination of Dr. Hedrick, twelve (12) months thereafter, or (b) in the case of a Severance Termination of Mr. Sims, nine (9) months thereafter. In order to be eligible for the benefits set forth above, such NEO must sign (and not revoke) a general release of claims in favor of the Company as of the date of the Severance Termination, as applicable (a “Release”).

If a Severance Termination occurs within the period beginning on the date the Company and an acquiror formally or informally agree on the terms of a transaction which, if consummated, would constitute a “change in control” and ending on the closing date of the change in control, or within twelve (12) months following a change in control, upon signing a Release (a “CoC Termination”), such NEO will be eligible to receive: (i) those items listed in the above paragraph under subclauses (ii) and (iii); (ii) an amount equal to (a)

in the case of a CoC Termination of Dr. Hedrick, eighteen (18) months of the greater of his base salary in effect immediately prior to the date of such CoC Termination and his base salary in effect on the date the terms of a transaction that results in a change in control are agreed to, or (b) in the case of a CoC Termination of Mr. Sims, twelve (12) months of the greater of his base salary in effect immediately prior to the date of such CoC Termination and his base salary in effect on the date the terms of a transaction that results in a change in control are agreed to; (iii) the amounts listed in the above paragraph under subclause (iv), except that, if the CoC Termination is for Dr. Hedrick, the amount of the COBRA payment will be increased to eighteen (18) months; (iv) the acceleration of such NEO’s remaining unvested equity incentive awards effective on the later of the CoC Termination and the date of the change in control; and (v) the right to exercise the equity incentive awards granted to him on or after the date of his Executive Employment Agreement until the later of (a) three (3) months after the CoC Termination, (b) three (3) months following the change in control with respect to any equity incentive awards that become exercisable upon a change in control due to the acceleration in connection with the change in control and (c) any period specified in such NEO’s award agreements (but not beyond the original expiration date of any equity incentive award). Further, even if a CoC Termination does not occur, if any of our NEOs remain employed by the Company as of the closing of such change in control, all of such NEO’s outstanding unvested incentive stock awards shall automatically accelerate on the date of such change of control.

Under the Executive Employment Agreements, the term “cause” generally refers to the occurrence of certain events including (i) the employee’s extended disability, (ii) the employee’s repudiation of his employment or his Executive Employment Agreement, (c) the employee’s conviction of a felony or certain misdemeanors, (iv) the employee’s demonstrable and documented fraud, (v) an intentional, reckless or grossly negligent action which causes material harm to the Company, (vi) an intentional failure to substantially perform material employment duties or directives, and (vii) the chronic absence from work for reasons other than illness, permitted vacation or resignation for good reason.

Under the Executive Employment Agreements, the term “good reason” generally refers to: (i) the Company’s material breach of its obligation to pay the employee the compensation earned for any past service (at the rate which had been stated to be in effect for such period of service); (ii) a change in the employee’s position with the Company which materially reduces the employee’s duties or stature in the business conducted by the Company; and (iii) a reduction in the employee’s level of compensation, provided, however, that a Company-wide reduction of compensation of not more than fifteen percent (15%) that is also applicable to all of the senior management of the Company and which continues for less than three (3) months, shall not constitute good reason.

Under the Executive Employment Agreements, the term “change of control” generally refers to (i) a change in the composition of the Board, as a result of which fewer than one-half (1/2) of the incumbent directors are directors who either: (a) had previously been directors of the Company; or (b) were elected, or were nominated for election, to the Board with the affirmative votes of at least a majority of the aggregate of the original directors who were still in office at the time of the election or nomination and the directors whose election or nomination was previously so approved; (ii) any “person” who, by the acquisition or aggregation of securities, is or becomes the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing fifty percent (50%) or more of the combined voting power of the Company’s then outstanding securities ordinarily having the right to vote at elections of directors (the “Base Capital Stock”); except that any change in the relative beneficial ownership of the Company’s securities, by any person, resulting solely from a reduction in the aggregate number of outstanding shares of Base Capital Stock, and any decrease thereafter in such person’s ownership of securities, shall be disregarded until such person increases, in any manner, directly or indirectly, such person’s beneficial ownership of any securities of the Company; (iii) the consummation of a merger or consolidation of the Company with or into another entity or any other corporate reorganization, if persons who were not stockholders of the Company immediately prior to such merger, consolidation or other reorganization own, immediately after such merger, consolidation or other reorganization, fifty percent (50%) or more of the voting power of the outstanding securities of each of (a) the continuing or surviving entity and (b) any direct or indirect parent corporation of such continuing or surviving entity; or (iv) the sale, transfer or other disposition of all or substantially all of the Company’s assets.

Retirement, Termination for Cause, or Resignation without Good Reason Arrangements

The Company does not have any agreements or plans, other than the Executive Employment Agreements, in place for the NEOs that would provide additional compensation in connection with a retirement, termination for cause or resignation without good reason.

DIRECTOR COMPENSATION

Our Board believes that the level of director compensation should be based on time spent carrying out Board and committee responsibilities and be competitive with comparable companies. In addition, the Board believes that a significant portion of director compensation should align director interests with the long-term interests of stockholders. The Board makes changes in its director compensation practices upon the recommendation of the Compensation Committee and following discussion and approval by the Board.

Our Board, following the Compensation Committee’s recommendation, approved the 2025 compensation of our non-employee directors, as described below. For 2026, the Compensation Committee approved an increase in certain of the retainers for our non-employee directors. The Board, following the Compensation Committee’s recommendation, approved a retainer of $13,750 per member of the Audit Committee, a $7,500 retainer per member of the Compensation Committee and a $5,000 annual retainer per member for the Nominating & Corporate Governance Committee.

On February 18, 2025, each non-employee director was awarded a grant of options for 40,122 shares as equity compensation and on August 13, 2025 awarded a grant of options for 297,794 shares as equity compensation.

The following table summarizes director compensation awarded to, earned by or paid to our non-employee directors who served on our Board during fiscal year 2025:

Pay Versus Performance Narrative Disclosure

In accordance with Item 402(v) of Regulation S-K, we are providing the following descriptions of the relationships between information presented in the Pay Versus Performance table on CAP and each of total shareholder return (“TSR”) and net loss.

We do not utilize TSR and net loss in our executive compensation program. However, we do utilize several other performance measures to align executive compensation with our performance. As described in more detail above in the section “Annual Bonuses and Non-Equity Incentive Plan Compensation,” part of the compensation our NEOs are eligible to receive consists of annual performance-based cash bonuses that are designed to provide our executives appropriate incentives to achieve defined annual corporate goals and to reward our executives for individual achievement towards these goals, subject to certain employment criteria. Additionally, we view stock options, which are an integral part of our executive compensation program, as related to company performance although not directly tied to TSR, because they provide value only if the market price of our Common Stock increases, and if the executive officer continues in our employment over the vesting period. These stock option awards strongly align our executive officers’ interests with those of our stockholders by providing a continuing financial incentive to maximize long-term value for our stockholders and by encouraging our executive officers to continue in our employment for the long-term.

With respect to net income, specifically, because we are not a commercial-stage company, we did not have any revenue during the periods presented, other than revenue associated with grants. Consequently, our company does not consider net loss as a performance measure for our executive compensation program.

The graphs below compare the compensation actually paid to our Chief Executive Officer and the average of the compensation actually paid to our remaining NEOs, with (i) our cumulative TSR, and (ii) our net income, in each case, for the fiscal years ended December 31, 2023, 2024 and 2025. TSR amounts reported in the graph assume an initial fixed investment of $100.

Equity Compensation Plan Information

The following table gives information, as of December 31, 2025, about shares of our Common Stock that may be issued upon the exercise of outstanding options, and shares remaining available for issuance under all of our equity compensation plans:

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth information regarding the beneficial ownership of our Common Stock as of March 18, 2026, by (i) each person, or group of affiliated persons, known to us to beneficially own more than five percent (5%) of the outstanding shares of our Common Stock, (ii) each of our directors, (iii) each of our named executive officers and (iv) all current directors and named executive officers as a group.

Information with respect to beneficial ownership is based on information furnished to us by each director or executive officer. Information about our 5% or greater stockholder, other than percentages of beneficial ownership, is based solely on Schedules 13G or 13D filed with the SEC. Beneficial ownership is determined according to the rules of the SEC and generally means that a person has beneficial ownership of a security if she, he or it possesses sole or shared voting or investment power of that security and includes options and warrants that are currently exercisable within 60 days of March 18, 2026. Options to purchase shares of our Common Stock that are exercisable within 60 days of March 18, 2026, are deemed to be beneficially owned by the persons holding these options for the purpose of computing percentage ownership of that person but are not treated as outstanding for the purpose of computing any other person’s ownership percentage. Except as indicated in the footnotes below, each of the beneficial owners named in the table below has, to our knowledge, sole voting and investment power with respect to all shares of Common Stock listed as beneficially owned by her, him or it, except for shares owned jointly with that person’s spouse or as may otherwise be set forth in a footnote.

We have based our calculation of beneficial ownership on 171,550,698 shares of our Common Stock outstanding as of March 18, 2026. Unless otherwise indicated, the address for each of the stockholders in the table below is c/o Plus Therapeutics, Inc., 6420 Levit Green Boulevard, Suite 310, Houston, Texas 77021.