Pfizer ends phase 2 extension study of PF-07868489 in pulmonary arterial hypertension

Pfizer has terminated a phase 2 open-label extension study of its pulmonary arterial hypertension (PAH) candidate PF-07868489, according to a ClinicalTrials.gov record (NCT07073820) last updated on 2026-11-02. The listing states that the study was terminated due to a business decision and was not based on any safety and/or efficacy concerns.¹

The trial, sponsored by Pfizer, had an actual start date of 2025-11-10 and was first posted on 2025-07-18. Both primary completion and overall study completion were recorded as 2026-10-09.

The study was designed to assess the long-term safety, tolerability and effects of the study medicine (PF-07868489) for the possible treatment of PAH.¹ The registry describes PAH as a disease marked by high blood pressure in the arteries that carry blood from the heart to the lungs, which makes it harder for the heart to pump blood through those lungs, potentially damaging the right side of the heart.¹

This was structured as an extension study of PF-07868489, allowing patients from an earlier qualifying study to continue participating to assess long-term benefits and safety of the medicine.¹ It enrolled 42 participants (actual)¹ in a single-group, open-label design. Participants were to receive subcutaneous doses of PF-07868489 every 4 weeks.¹

Primary outcome measures included treatment-emergent adverse events, serious adverse events, laboratory test changes, and vital sign abnormalities, each tracked from baseline up to week 111.¹ The study spanned 27 sites in 10 countries, including the United States, Australia, Belgium, China, Czechia, Germany, Japan, South Korea, Spain, and the United Kingdom.¹