Exhibit 16.1

July 18, 2025

Securities and Exchange Commission

100 F Street N.E.

Washington, D.C. 20549

We have been furnished with a copy of the response to Item 4.01 of Form 8-K for the event that occurred on July 16, 2025, to be filed by our former client, Plus Therapeutics, Inc. We agree with the statements made in response to that Item insofar as they relate to our Firm.

 

Very truly yours,

/s/ BDO USA P.C.