Bristol Myers radiopharma cancer drug slows rare tumor progression in study (updated)

Bristol-Myers Squibb

12/10/2026 12:21

Updates shares and adds analyst comment in 8 and 12
By Siddhi Mahatole
Oct 12 (Reuters) - Bristol Myers Squibb BMY.N said on Monday its experimental radiopharmaceutical cancer therapy significantly delayed disease progression in patients with rare, advanced gastrointestinal and pancreatic tumors that had progressed after earlier treatment.
Shares of the drugmaker were up nearly 2%.
The therapy, RYZ101, which Bristol Myers added through its $4.1 billion takeover of RayzeBio, belongs to a closely watched class of cancer therapies that act like a 'cannonball' to kill cancer cells by delivering radioactive particles to tumorous tissue or tumor-associated cells. 
RYZ101 uses the radioactive isotope actinium-225. The late-stage trial tested it against standard-of-care treatments in patients with gastroenteropancreatic neuroendocrine tumors, or GEP-NETs,  whose disease had progressed after Lutetium-177-based therapy. 
GEP-NETs are rare cancers that arise in hormone-producing cells of the gastrointestinal tract and pancreas.
     Major drugmakers, including AstraZeneca AZN.L and Eli Lilly LLY.N, have invested heavily in next-generation radiopharmaceutical therapies that use radioactive isotopes to target tumors.
Wall Street is keenly focused on whether RYZ101 and similar therapies can build on the success of Novartis' NOVN.S radiopharmaceutical drugs and help patients whose disease progresses after currently available therapies.
RBC Capital Markets analysts said the results validate Bristol Myers' radiopharmaceutical platform and may boost confidence in rival programs across the sector.
Bristol Myers said the drug's safety profile was consistent with previous studies and that it planned to discuss the data with regulators. 
The company did not disclose detailed data from the study, saying results would be presented at a future medical meeting.
Patients will continue treatment and be followed for overall survival.
Cantor Fitzgerald analyst Carter Gould was more cautious, saying RYZ101 is likely to be only a modest commercial driver for Bristol Myers, given that newer lead-212 alpha-emitting therapies are advancing into earlier lines of treatment and could shrink the drug's addressable market.
RYZ101 is also being studied in early-stage trials in hormone receptor-positive metastatic breast cancer. 
     

(Reporting by Siddhi Mahatole in Bengaluru; Editing  by Tasim Zahid)
((siddhi.mahatole@thomsonreuters.com;))