Gilead Sciences' CD47 cancer program is back on track—for the most part—after the FDA lifted clinical holds placed in January on five trials.
But the agency is keeping two additional trials on ice, Gilead said Monday after the market closed.
Trials for the CD47-targeting med, magrolimab, were placed on hold due to an “apparent imbalance” in adverse reactions seen in the study arms. The sweeping action covered five trials from early- to late-stage development for the therapy in combination with azacitidine for patients with myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and myeloid malignancies. This included several phase 3 trials called ENHANCE.
The FDA has now wrapped up its review of magrolimab in AML and MDS but will keep the holds on two additional trials in patients with diffuse large B-cell lymphoma and multiple myeloma. Gilead did not elaborate on why the holds were still in place but said it was working with the agency.
Monday’s news comes more than two months after the holds were first placed on the program. At first, Gilead disclosed that five trials received clinical holds—the same five that were cleared today. But days later, in a fourth-quarter earnings report, the company disclosed that two additional trials—for diffuse large B-cell lymphoma and multiple myeloma—had also been hit with a partial clinical hold. Those studies were not testing magrolimab in combination with azacitidine. The company made the decision at that time to discontinue one phase 1b trial for patients with higher-risk MDS.
Gilead expressed confidence in the drug’s safety profile after the holds were lifted, just as CEO Daniel O'Day did during fourth-quarter earnings in February.
“We look forward to continuing our work developing magrolimab and advancing this potential cancer treatment option,” Chief Medical Officer Merdad Parsey, M.D., Ph.D., said in a Monday statement.
For the trials that are now cleared, enrollment can resume. Luckily for Gilead, the pre-specified enrollment benchmark had already been met for interim data in the ENHANCE MDS study prior to the hold. As a result, the company said a planned 2023 readout is still on track.
The trials are centered on the company’s monoclonal antibody targeting CD47, a protein that supports tumor proliferation and growth. The hope is that by limiting the receptor, the body’s macrophages can clear out tumorous cells that may otherwise spread. Magrolimab received breakthrough designation from the FDA in September 2020.