Flexion Therapeutics Inc. submitted a new drug application to the U.S. Food and Drug Administration for its lead investigational product candidate Zilretta, which is being evaluated to treat patients with osteoarthritis of the knee.

Zilretta has also received a fast-track designation from the FDA.

The new drug application is supported by results from a phase 3 clinical trial, which showed a highly significant reduction in average daily pain versus placebo at week 12, with durable and clinically meaningful pain relief in patients with moderate to severe osteoarthritis knee pain.