The results came in a Phase 3 trial of PF-06410293, a compound known as a biosimilar because it is almost identical to, and interchangeable with, a biological treatment that already has U.S. Food and Drug Administration (FDA) approval.
The randomized, double-blind REFLECTIONS B538-02 trial (NCT02480153) compared Humira’s and PF-06410293’s effectiveness, safety and ability to trigger an immune response in combination with methotrexate.
The measuring stick for the results was the American College of Rheumatology 20’s (ACR20’s) response rate at week 12.
Because biosimilar compounds are more affordable than the original therapy, they are intended to create competition. The U.S. Patient Protection and Affordable Care Act promotes biosimilar development.
The Phase 3 study included about 560 patients with moderate to severe rheumatoid arthritis who had had an inadequate response to methotrexate alone.
A key focus of the trial was the number of patients responding to the treatment by the 12th week. The ACR20 scale considers a response to be a 20 percent disease in arthritis activity.
Researchers also assessed whether there were fewer manifestations of the disease, less pain, and improvements in tender joint count, swollen joint count, and an inflammation measure known as the C-reactive protein count.
“Today’s announcement builds on Pfizer’s robust biosimilar pipeline which has now delivered positive top-line data results for three of our proposed biosimilars,” Sumant Ramachandra, MD, PhD, and the head of Pfizer Essential Health’s Research and Development division, said in a press release. “As the leading global biosimilars company, we continue to advance our commitment to expand access to high-quality treatment options for patients living with chronic, debilitating conditions, such as those in inflammation. Inflammation remains one of the core research areas for Pfizer, spanning over 60 years and including a number of assets in various stages of development.”
PF-06410293 is the second inflammation biosimilar that Pfizer has developed. It’s also the third Pfizer biosimilar in four months to demonstrate an effectiveness similar to the original treatment.
Pfizer’s Inflectra is the first biosimilar monoclonal antibody (mAb) therapy the FDA has approved as an alternative to Remicade (infliximab) for treating rheumatoid arthritis.
Pfizer has eight biosimilars in mid- to late-stage development, and several in early-stage development.