Pfizer has halted a Phase 2 trial of PF-06835375, its CXCR5 antibody being tested in primary immune thrombocytopenia, an autoimmune blood disorder, calling the move a business decision while remaining tight-lipped on whether the program has a future, Fierce Biotech reported on October 20. Endpoints News carried the same trial-ending item the same day. Pfizer did not disclose efficacy or safety data for the study.
The decision is portfolio hygiene more than a readout. Primary immune thrombocytopenia is a small indication where Novartis and Amgen already hold the established positions, and the company continues other programs in the autoimmune space. With no data released, the outside read is that Pfizer is choosing not to spend on a program where the commercial path runs through entrenched rivals rather than abandoning an immunology thesis.
The quiet handling is the point to watch. Companies that end a study on a clear efficacy or safety miss usually say so; a “business decision” with no data and no forward plan leaves the door nominally open while removing the spend. In Pfizer’s current posture, post COVID revenue step-down and under a cost program, that is the standard move for a mid-stage asset that no longer clears the internal bar.