Pfizer’s Abrocitinib Atopic Dermatitis Study Nears Data Milestone: What Investors Should Watch

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

Study Overview: Pfizer is running a large, long-term phase 3 trial (NCT03422822) called “A Phase 3 Multi-Center, Long-Term Extension Study Investigating the Efficacy and Safety of Abrocitinib, With or Without Topical Medications, Administered to Subjects Aged 12 Years and Older With Moderate to Severe Atopic Dermatitis.” The goal is to track how well abrocitinib works and how safe it is over time in people who already completed earlier abrocitinib studies, focusing on patients with moderate to severe atopic dermatitis. The study is important because it supports long-term use, including in teens, which can help shape labeling, uptake, and payer decisions for Pfizer’s atopic dermatitis franchise.

Intervention/Treatment: The study tests abrocitinib, an oral small-molecule drug, given once daily at 100 mg or 200 mg doses, with or without standard topical creams. It is designed to control moderate to severe atopic dermatitis symptoms over the long term. Some patients may receive placebo temporarily or switch doses as part of the trial plan. The aim is to confirm sustained benefit and safety at doses that can be used in real-world practice.

Study Design: This is an interventional, randomized, phase 3 trial with parallel treatment groups. Patients are randomly assigned to different dose plans, which helps reduce bias. The study uses “quadruple masking,” meaning patients, their doctors, the study investigators, and the people who assess outcomes do not know who is on which treatment at key stages. The main purpose is treatment, not just observation, with the focus on long-term control of disease signs, symptoms, and side effects.

Study Timeline: The study was first submitted on December 20, 2017, marking the formal start of regulatory tracking and setup. It has now reached “Completed” status, indicating that treatment and follow-up have ended and data collection is finished. While primary and final completion dates are not listed in the summary, the most recent update on the ClinicalTrials portal is January 9, 2026, signaling that Pfizer has refreshed or finalized key information, likely including endpoints and safety follow-up, and is moving toward or is already in the data analysis and reporting phase.

Market Implications: For investors, the completion and recent update of this long-term extension study is a key milestone for Pfizer (PFE) in atopic dermatitis. Abrocitinib’s commercial success depends heavily on evidence of durable benefit and a clean safety profile, especially in younger patients. Strong long-term data can support broader physician adoption, better formulary access, and potentially higher peak sales in a crowded market that includes biologics like Sanofi/Regeneron’s Dupixent and other JAK inhibitors from AbbVie and others. If final results confirm sustained efficacy and manageable risk, sentiment around Pfizer’s immunology pipeline could improve, supporting the stock’s medium-term narrative. Conversely, any new safety signals, particularly in adolescents (including the bone MRI sub-study findings), could weigh on uptake and pressure the share price, while favoring competitors. The timing of this update suggests investors should watch for upcoming data disclosures in earnings calls or medical conferences, as these could act as catalysts for PFE and inform relative positioning versus peers in the dermatology and immunology space.

The study has completed follow-up and was recently updated, with more detailed information available on the ClinicalTrials.gov portal.

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