By Reuters

(Reuters) - Shares of Fulcrum Therapeutics plunged 50% in premarket trading on Tuesday after the company said it would abandon development of ‌its experimental sickle-cell disease drug following cancer-risk concerns raised by the U.S. ‌FDA, and explore strategic options including a potential sale or merger.

The oral drug, pociredir, was being tested ​to treat sickle-cell disease, an inherited blood disorder that can trigger pain, anemia and organ damage and reduce life expectancy.

The setback adds to a string of challenges in sickle-cell drug development. In 2024, Pfizer withdrew its approved therapy Oxbryta and stopped related ‌studies over safety concerns.

Pociredir was ⁠designed to increase levels of fetal hemoglobin by targeting a key sub-unit in the PRC2 protein complex, which normally suppresses its ⁠production.

Fulcrum's decision followed feedback from the U.S. Food and Drug Administration over safety concerns linked to drugs targeting the protein complex, after Ipsen's cancer drug, Tazverik, was withdrawn globally ​earlier this ​year because of the risk of secondary ​blood cancers.

The company said it ‌had submitted data arguing that pociredir, which targets a different component of the PRC2 complex than Tazverik, had a distinct risk profile. The FDA, however, concluded that all drugs acting on the complex pose similar malignancy risks.

Truist analyst Gregory Renza said the regulator did not differentiate between sub-units of the PRC2, instead viewing the entire ‌complex as carrying a systemic cancer risk.

The FDA ​also cited earlier preclinical malignancy signals linked to ​pociredir, Fulcrum said.

The stock is ​down about 43% year-to-date, according to LSEG data.

The company also said ‌it would now consider strategic alternatives, ​including a potential sale ​or merger, and has begun cutting costs to preserve cash. It reported $333.3 million in cash and investments as of March 31.

Fulcrum said no new ​safety concerns had emerged in ‌clinical trials and that the drug had shown increases in fetal hemoglobin, ​which can help reduce disease severity in sickle-cell patients.

(Reporting by Siddhi ​Mahatole in Bengaluru; Editing by Diti Pujara)

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