Fulcrum scraps sickle cell drug program after FDA raises cancer-risk concerns

Ipsen SA

01/06/2026 22:06

    June 1 (Reuters) - Fulcrum Therapeutics FULC.O said on Monday it would stop developing its experimental sickle-cell disease drug after the U.S. Food and Drug Administration raised cancer-risk concerns, which left no viable regulatory path for the treatment.
The drug developer's shares slumped nearly 50% in extended trading.
The drug, pociredir, was being developed as an oral treatment for sickle-cell disease, an inherited blood disorder that can cause pain, anemia, organ damage and reduced life expectancy.
Fulcrum said the FDA concerns were tied to secondary blood cancers seen with Ipsen's IPN.PA cancer drug, Tazverik, which was withdrawn globally in March.
The company said it submitted information to the FDA supporting the position that mechanistic differences between the two drugs' target were relevant to the benefit-risk assessment.
The FDA, however, concluded that any drug that targets the protein PRC2 carries risk.
"We arrived at this decision after discussion with the FDA, and despite robust elevations in fetal hemoglobin seen with pociredir and the potential for clinical benefit, we do not see a path forward with pociredir," said Fulcrum CEO Alex Sapir. 
Fetal hemoglobin is a form of hemoglobin linked to clinical benefit in sickle-cell disease.
Fulcrum will explore options including a merger, acquisition, business combination or other transaction, and has initiated efforts to cut operating expenses and preserve cash.

 (Reporting by Kunal Das in Bengaluru; Editing by Shilpi Majumdar)
 ((Kunal.Das2@thomsonreuters.com;))