Flexion Therapeutics OA Drug Meets Primary Endpoint

Good news for Flexion Therapeutics, Inc., as its knee osteoarthritis (OA) drug Zilretta met its primary endpoint at week 12. Zilretta (also known as FX006) demonstrated highly significant, durable and clinically meaningful pain relief against placebo in patients with moderate to severe OA knee pain.

According to the February 16, 2016 news release, the trial involved 486 patients at approximately 40 centers worldwide. Patients were randomized to one of three treatment groups (1:1:1) and received either a single IA injection of 40 mg of Zilretta, normal saline (placebo) or 40 mg of immediate-release TCA.

Flexion CEO Michael D. Clayman, M.D, told OTW, “Most surgeons are already aware that current OA therapies either carry black box warnings for systemic side effects, or in the case of injectables, lack either magnitude or duration of pain relief. Of particular note is an issue that has been addressed by the AAOS [American Academy of Orthopaedic Surgeons], that of the growing opioid epidemic. Opioid addiction has emerged as a prominent public health issue, and yet we haven’t had a meaningfully innovative OA therapy approved in over a decade. Zilretta has the potential to be such an advance to OA treatment. Zilretta is the first-ever sustained release steroid for IA injections and is designed to provide persistent concentrations of drug locally that both amplify the magnitude and prolong the duration of pain relief relative to standard immediate-release steroid injections.”

“Our pivotal Phase 3 study showed that Zilretta patients experienced, on average, a 50 percent reduction in pain from baseline over weeks 1 through 12. Zilretta also achieved statistically significant and clinically meaningful pain relief at weeks 1 through 16 against placebo, as well as statistical significance on a commonly used assessment of pain, stiffness and function (WOMAC A (pain), WOMAC B (stiffness) and WOMAC C (function)) through week 12 against both placebo and immediate-release triamcinolone acetonide. We are very pleased with these results and look forward to discussing the results with the FDA.”

Asked about the next 9-12 months, Dr. Clayman stated, “These data are an important milestone for Zilretta, which has received Fast-Track designation by the FDA. At this time, we will move rapidly to schedule a Pre-NDA [new drug application] meeting with FDA, as we continue to plan for an NDA filing in the second half of 2016. Also, we plan to prepare and present detailed results from the Phase 3 clinical trial at an upcoming scientific meeting.”

“In addition to regulatory steps, our current focus is to expand the organization to support needed activities in manufacturing and commercialization. Our greatest competitive advantage is our people, and we are seeking to recruit people who have functional expertise and who embody our vision to expeditiously deliver much needed therapies to the many OA patients who have limited treatment options.”