Pfizer Ends Early-Stage Lymphoma Combo Trial, Trimming a Small Piece of Its Oncology Upside

Pfizer Inc (PFE) announced an update on their ongoing clinical study.

Pfizer Inc. (PFE) has terminated a Phase 1b/2 cancer trial titled “A Phase 1B/2, Open-Label Study of PF-07901801 in Combination With Glofitamab After a Fixed, Single Dose of Obinutuzumab in Participants With Relapsed/Refractory Diffuse Large B Cell Lymphoma Not Eligible for Stem Cell Transplantation.” The study aimed to test a new three-drug combo for hard-to-treat lymphoma and find a safe, effective dose of Pfizer’s experimental drug maplirpacept.

The treatment combined three infused medicines. Maplirpacept (PF-07901801) is Pfizer’s early-stage cancer drug, given with Roche’s bispecific antibody glofitamab (Columvi) and the antibody obinutuzumab (Gazyva). The goal was to boost the immune attack on lymphoma cells in patients who cannot receive stem cell transplant or CAR-T therapy.

The trial was an interventional study in two parts. In Phase 1b, small patient groups received rising doses of maplirpacept with fixed doses of glofitamab and obinutuzumab to find safe dose levels. In Phase 2, patients would have been randomly assigned to one of three maplirpacept dose levels, with all participants knowing what they received because the study was open-label and not blinded.

The study was first submitted on 10 May 2023, marking the formal start of the clinical program. The planned timeline included a Phase 1b dose-finding stage followed by a larger Phase 2 efficacy stage. While primary and final completion dates are not posted, the key update is that the study status is now “terminated,” with a last protocol update submitted on 05 May 2026, signaling an early stop ahead of full enrollment and readout.

For investors, the termination reduces near-term optionality around PF-07901801 in lymphoma and slightly softens Pfizer’s long-term oncology pipeline story. The impact on PFE shares is likely modest given the early stage and small size of the program, especially as Roche’s Columvi and Gazyva remain in use and other bispecific and cell therapies continue to reshape the lymphoma space, keeping competitive pressure high across the sector.

The study has been formally terminated and the latest information is available on the ClinicalTrials portal for investors who want more detail on the reasons and implications.

To learn more about PFE’s potential, visit the Pfizer Inc drug pipeline page.