Pfizer announced positive results from the company’s comparative, confirmatory REFLECTIONS B538-02 study for the investigational monoclonal antibody PF-06410293, a potential Humira (adalimumab) biosimilar, saying that the study met primary objectives by demonstrating equivalent efficacy as measured by the American College of Rheumatology 20 (ACR20) response rate at week 12 in adult patients with moderate to severe arthritis.
The ACR20 response is defined as ≥20% improvement in tender joint count; ≥20% improvement in swollen joint count; and ≥20% improvement in at least 3 of 5 remaining ACR core measures: participant assessment of pain; participant global assessment of disease activity; physician global assessment of disease activity; self-assessed disability (according to the disability index of the Health Assessment Questionnaire [HAQ]); and C-reactive protein (CRP).
The REFLECTIONS B538-02 trial is evaluating the efficacy, safety, and immunogenicity of PF-06410293 compared with Humira, with each being taken in combination with methotrexate when administered subcutaneously. REFLECTIONS B538-02 is a multinational, randomized, double-blind, two-arm, parallel group equivalence study conducted in 597 patients who have had an inadequate response to methotrexate therapy. The ongoing phase 3 study began in June 2015 and is expected to be completed in December 2017.
Sumant Ramachandra, MD, PhD, MBA, Head of Research and Development, Pfizer Essential Health, said the positive study results for PF-06410293 build on the company’s robust biosimilar pipeline, which consists of eight distinct biosimilar molecules in mid- to late-stage development and several others in early-stage development.
The newest data from PF-06410293 represent Pfizer’s second proposed biosimilar for inflammatory conditions and third proposed biosimilar pipeline molecule to report positive top-line results within the past 4 months.