Fulcrum Therapeutics (FULC) is having a rough week. On Monday, the company announced it was pulling the plug on pociredir, its lead experimental drug for sickle cell disease, after the Food and Drug Administration raised serious safety concerns. The stock initially cratered but has since recovered a bit — shares were up about 2% on Thursday to around $3.29, though that's still dangerously close to the 52-week low of $2.83.
The problem? The FDA is worried that pociredir, which targets a protein called EED in the PRC2 complex, could cause secondary hematologic malignancies — basically, cancers that develop as a side effect of treatment. Those fears were amplified by the experience of another drug, Tazverik (tazemetostat), which targets a different part of the same complex (EZH2) and was pulled from the global market in March 2026 after showing an unexpectedly high rate of these cancers.
Fulcrum tried to argue that pociredir was different. The company submitted data to the FDA suggesting that the mechanistic differences between targeting EED versus EZH2 — which play distinct biological roles — should matter for the risk assessment. But the FDA wasn't buying it. The agency concluded that any drug that messes with the PRC2 complex carries the same malignancy risk, regardless of which specific subunit it targets. And given that pociredir had already shown some preclinical malignancy signals, there was no viable regulatory path forward.
So Fulcrum is now left with a big hole in its pipeline and a stock that's down more than 50% from its 20-day moving average. The company is launching a strategic review to explore options, which could include a merger or acquisition. In biotech speak, that often means "we're putting a 'for sale' sign up."














