Plus Therapeutics Inc美股招股说明书(2026-01-14版)

We are offering, in a firm commitment underwritten offering, 39,473,684 units, with each unit consisting of (i) one share of our common stock, and (ii) one warrant to purchase oneshare of our common stock at a public offering price of $0.38 per unit. The shares of common stock and the accompanying warrants can only be purchased together in this offering but will be issued separately and will be immediately separable uponissuance. Pursuant to the registration statement of which this prospectus forms a part, we are also registering the shares of common stock issuable upon exercise of the warrants included in theunits offered hereby. The warrants will not be listed on the Nasdaq Capital Market or trade in any market. However, we anticipate that the shares of our common stock to be issued upon exercise of thewarrants will trade on the Nasdaq Capital Market. This prospectus also relates to the shares of common stock issuable upon the exercise of the warrants. We have engaged Lake Street Capital Markets, LLC to act as our underwriter in connection with this offering. We have agreed to pay to the underwriter the underwriting fees set forthin the table below. Further, any proceeds from the sale of securities offered by us will be available for our immediate use, despite uncertainty about whether we would be able to use suchfunds to effectively implement our business plan. See the section entitled “Risk Factors” for more information. We will bear all costs associated with the offering. See “Underwriting” on page115 of this prospectus for more information regarding these arrangements. Our common stock is listed on the Nasdaq Capital Market under the symbol “PSTV.” The closing price of our common stock on the Nasdaq Stock Market on January6, 2026, was$0.56 per share. There is no established trading market for the warrants, and we do not expect a market to develop. We do not intend to apply for a listing of the warrants on any securities exchange orother nationally recognized trading system. Without an active trading market, the liquidity of the warrants will be limited. Investing in our securities involves a high degree of risk. These risks are described in the “Risk Factors” section on page 6 of this prospectus. Youshould also consider the risk factors described or referred to in any applicable prospectus supplement, before investing in these securities. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus istruthful or complete. Any representation to the contrary is a criminal offense. PerUnitTotalPublic offering price$0.38$15,000,000Underwriter’s discounts and commissions(1)$0.0266$1,050,000Proceeds to us, before expenses$0.3534$13,950,000 (1)We have agreed to reimburse the underwriter for certain expenses. See “Underwriting” on page 115 for additional information regarding underwriting compensation. We have also granted the underwriter an option to purchase up to 5,921,052 additional shares of common stock and up to 5,921,052 additional Warrants, or any combination thereof, solely tocover over-allotments, if any. The underwriter may exercise this option at any time and from time to time during the 30-day period from the date of this prospectus. Delivery of the securities offered hereby is expected to be made on or about January 15, 2026. Lake Street The date of this prospectus is January13, 2026 Table of Contents TABLE OF CONTENTS ABOUT THIS PROSPECTUSPROSPECTUS SUMMARYTHE OFFERINGRISK FACTORSCAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTSUSE OF PROCEEDSDILUTIONMANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONSBUSINESSMANAGEMENTCORPORATE GOVERNANCEEXECUTIVE COMPENSATION Table of Contents ABOUT THIS PROSPECTUS You should read this prospectus and the related exhibits filed with the Securities and Exchange Commission (the “SEC”), together with theadditional information described under the heading “Where You Can Find More Information” before making your investment decision. You should rely only on the information provided in this prospectus or in a prospectus supplement or any free writing prospectuses or amendmentsthereto. Neither we, nor the underwriter, have authorized anyone else to provide you with different information. If anyone provides you with different orinconsistent information, you should not rely on it. You should assume that the information in this prospectus is accurate only as of the date hereof. Ourbusiness, financial condition, results of operations and prospects may have changed since that date. Neither we, nor the underwriter, are offering to sell or seeking offers to purchase these securities in any jurisdiction where the offer or sale is notpermitted. We have not done anything that would permit this offering or possession or distribution of this prospectus in any jurisdiction where action forthat purpose is required, other tha