The dream of using anti-CD47 drugs to boost chemotherapy in blood cancer patients is unraveling fast. Weeks after Gilead Sciences stopped its phase 3 trial for futility, ALX Oncology has called a halt to a pair of studies for a rival therapy.

Gilead’s $4.9 billion oncology bet has hit a late-phase setback. Spooked by an “apparent imbalance” in adverse reactions between study arms, the FDA has imposed a partial clinical hold on a handful of trials of magrolimab—raising questions about the program and the billions biopharma has bet on CD47.

Kahr Medical has raised $18 million (€17 million) to take an anti-CD47 drug into the clinic. The money will fund early-phase development of a CD47x4-1BB bispecific that Kahr plans to test as a single agent and in combination with Roche’s checkpoint inhibitor Tecentriq.