Dive Brief:
- The Food and Drug Administration has suspended almost half of the clinical studies involving an experimental cancer drug Gilead acquired two years ago in a transaction valued at about $5 billion, the latest blow to the company's efforts to expand its oncology business.
- Trial investigators reported an "apparent imbalance" in suspected, unexpected adverse reactions in studies testing the drug, known as magrolimab, alongside the blood-cancer medicine azacitidine. While Gilead didn't provide specifics, the company said it will stop screening and enrolling patients in all trials involving the treatment combination.
- The decision brings to a halt three Phase 3 studies in certain blood malignancies, among them a test in front-line acute myeloid leukemia, and will impact two other earlier stage trials. Another six ongoing or planned magrolimab studies in solid tumors are unaffected, Gilead said in a Tuesday statement.
Dive Insight:
The news is a setback for Gilead's development plans and may raise concerns about its broader strategy in oncology.
On one hand, deals over the last decade for Calistoga Pharmaceuticals, Kite Pharma and most recently, Immunomedics have each yielded approved therapies. Gilead has won FDA OKs for three cancer medicines in the last four years and since 2020 has signed a series of alliances and acquisitions meant to add several more prospects.
Still, approvals haven't always led to fast sales or broad adoption and the research partnerships Gilead has signed may not pan out.
For example, a wide-ranging partnership with Arcus Biosciences hasn't paid dividends so far. Gilead withdrew two indications for the blood-cancer medicine Zydelig earlier this month and yesterday a myelofibrosis drug it acquired for about half a billion dollars and later sold for $3 million found success in the hands of a smaller biotech company.
Now magrolimab, acquired in Gilead's $4.9 billion acquisition of Forty Seven in 2020, faces a more uncertain future.
Magrolimab blocks a signaling mechanism cancerous cells use to shield themselves from the immune system. It's part of an emerging class of drugs viewed by Gilead and others as the potential backbone for new immunotherapy combinations. More than a dozen are in clinical trials and Pfizer bought Trillium Therapeutics for $2.3 billion to get ahold of one last year. Gilead even had openly discussed a potential accelerated approval for magrolimab in myelodysplastic syndrome.
But the opportunities for the drug appear to be "rapidly dwindling," wrote Brian Skorney, an analyst at Baird, in a Wednesday note to clients. Gilead's drug has faced multiple delays and now its "best shot" as a treatment for AML and myelodysplastic syndrome has been put on hold, he said.
Gilead said it hasn't identified a new safety signal or trend from the adverse reactions reported. Still, it didn't share more details and the situation "will only add to questions" around its buyout of Forty Seven, Skorney added.
Gilead's dealmaking strategy outside of oncology has drawn skepticism as well. A $5 billion alliance with Galapagos hasn't worked out, raising the stakes for a critical study in breast cancer that is expected to produce results imminently. That study is viewed as particularly important to the future of Trodelvy, the drug it acquired by buying Immunomedics for $21 billion last year.