Pfizer Drops Lung Drug, Trims Obesity Pipeline

The company cites business reasons for ending the pulmonary hypertension candidate, a research-stage drug not yet available to patients.

Updated on Nov. 3, 2026 in Biotech

Bold flat-color editorial illustration of a row of identical glass vials with two removed, set on cream, in deep red and cream palette. — Pfizer ended a phase 2 study of its pulmonary hypertension candidate PF-07868489 and trimmed obesity programs, citing business reasons rather than safety or efficacy concerns. AI Illustration. Upload story photo >

Pfizer has terminated its phase 2 open-label extension study of PF-07868489, a candidate for pulmonary arterial hypertension, one year after it began, citing business reasons rather than safety or efficacy concerns. The company disclosed the move with its third-quarter financial results. The candidate is research-stage, not an approved or marketed product.

Why it matters

The termination signals a pruning of Pfizer's pipeline as it reprioritizes programs, including two obesity assets and several phase 1 efforts cut in the same update. For the broader drug-development field, business-driven discontinuations of mid-stage candidates show how portfolio decisions, rather than clinical data alone, determine which experimental therapies advance.

The disclosure is a corporate pipeline update, so the evidence is company-reported status rather than trial results. Pfizer's stated reason is business grounds, with no safety or efficacy findings released for PF-07868489 in the source.

The players

Pfizer

A large pharmaceutical company whose pipeline spans small-molecule and biologic candidates across cardiovascular, oncology, and metabolic disease areas.

The details

PF-07868489 is an experimental drug being tested for pulmonary arterial hypertension, a condition in which blood pressure in the lung arteries is abnormally high. The phase 2 open-label extension is a follow-up study in which participants continue receiving the drug without a comparison group, and Pfizer ended it after one year, with the study originally due to finish in the second half of 2028. Alongside this, Pfizer ended a phase 1 trial of two assets it acquired from Metsera, which are obesity-related drug candidates.

2023: Pfizer started the phase 1/2 trial of PF-07868489.
2025: Pfizer began the phase 2 open-label extension of PF-07868489.
May: Pfizer terminated a phase 1 study of the KRAS inhibitor PF-07985045 on business grounds.
July: Pfizer stopped enrollment in a phase 1 trial of the KRAS inhibitor PF-07934040.

The Tech Race

Pfizer's cuts come as obesity drug development remains crowded, with its GIPR agonist and antagonist programs among the candidates it has now trimmed. Pruning weaker assets concentrates resources on the programs Pfizer keeps active in the same competitive field.

Patients with pulmonary arterial hypertension will not see PF-07868489 become available through this decision, and no timeline for any replacement therapy from Pfizer was given. The termination does not change any currently approved treatment.

The takeaway

Pfizer's decision shows that business priorities, not only clinical signals, can end a candidate's development. Watch Pfizer's next quarterly pipeline update for whether it confirms further obesity-program changes.