Pfizer has announced that its confirmatory study REFLECTIONS B537-02, which evaluated the efficacy, safety, and immunogenicity of PF-06438179 (infliximab-Pfizer) compared to Remicade (infliximab), met its primary endpoint.

This trial showed equivalent efficacy of the proposed biosimilar PF-06438179 to the originator product as measured by the American College of Rheumatology 20 (ACR20) response at week 14.

PF-06438179 is being developed as a potential biosimilar to Remicade.

A Phase 3, multi-national, randomised, double blind, two-arm, parallel group study, REFLECTIONS B537-02 is intended to review the safety, efficacy, and immunogenicity of PF-06438179 (infliximab-Pfizer) versus Remicade in combination with methotrexate when administered intravenously to treat patients with moderate to severely active rheumatoid arthritis (RA).

"The primary endpoint is ACR20 response (a greater than or equal to 20% improvement by ACR criteria) at week 14 of the study treatment."

These patients have had an inadequate response to methotrexate therapy.

The study is also intended to evaluate clinical response, safety and immunogenicity after study drug transitioning from Remicade to PF-06438179 after 30 or 54 weeks of Remicade treatment.

The primary endpoint is ACR20 response (a greater than or equal to 20% improvement by ACR criteria) at week 14 of the study treatment.

Evaluation at both earlier time points (weeks two, four, six and 12) and later time points (weeks 22 and 30) will be used to support the primary endpoint analysis.

PF-06438179 (Infliximab-Pfizer) is a chimeric human-murine monoclonal antibody (mAb) against tumour necrosis factor (TNF). It is currently in development as a potential biosimilar for all approved indications of Remicade (infliximab).

Remicade is currently approved in the US and EU for rheumatoid arthritis (RA), Crohn's disease, pediatric Crohn’s disease, ulcerative colitis, pediatric ulcerative colitis, ankylosing spondylitis, psoriatic arthritis, and plaque psoriasis.

Regulatory authorities have not established biosimilarity.

Investigational compound PF-06438179 has not secured regulatory approval in any country.

In February, Sandoz secured the rights from Pfizer for the development, commercialisation and manufacture of PF-06438179 in the 28 countries comprising European Economic Area (EEA).

As per the sale, Pfizer retains commercialisation and manufacturing rights to PF-06438179 (a proposed biosimilar to Remicade) in countries outside the EEA.