Flexion Reports Impressive Q1 Sales and Updated Clinical Data

Burlington, Massachusetts-based Flexion Therapeutics, Inc., a biopharmaceutical company focused on therapies for musculoskeletal conditions, has announced its first quarter sales for ZILRETTA^® and released promising preliminary data from its gene therapy trial for osteoarthritis (OA) knee pain.

Flexion Therapeutics manufactures ZILRETTA, an extended-release, non-opioid treatment for OA knee pain. For the first quarter of 2021, ZILRETTA had net sales of $24.6 million from 2,044 accounts purchasing ZILRETTA. For the past year, demand for ZILRETTA has increased every quarter.

OTW spoke with Flexion Therapeutics CEO Michael Clayman, M.D. about ZILRETTA’s impressive first quarter. Dr. Clayman discussed the challenges of the first quarter of 2021 including the impact of the COVID-19 vaccinations on demand, severe weather shutting down parts of the country, and the residual impacts of the COVID-19 pandemic on patients receiving treatment.

Dr. Clayman told OTW, “To have a quarter of $24.6 million in sales with demand for ZILRETTA increasing over the prior quarter, that’s a very strong performance, and we were quite pleased with that.”

In addition to an impressive quarter for ZILRETTA, Flexion Therapeutics also shared promising results from its first-in-human Phase 1 dose escalation trial of FX201. FX201 is an investigational “helper-dependent adenoviral gene therapy” for OA. It is injected into the joint space and, per the press release, is “intended to deliver as-needed anti-inflammatory activity to joint tissues.”

Preliminary data from the low-dose cohort revealed that “improvement in WOMAC-A (Western Ontario and McMaster Universities Arthritis Index) pain from baseline was observed in four of the five patients at [w]eek 12 and 24 and in two of the three patients with [w]eek 52 data.”

Further promising results from the study include improved KOOS (Knee Injury and Osteoarthritis Outcome Score) scores. The study reported that “[f]unctional improvement from baseline assessed by the KOOS questionnaire was observed in four of the five patients at [w]eek 24, and all three patients with [w]eek 52 data reported an improved KOOS score compared to baseline at [w]eek 52.”

Dr. Clayman discussed the trial results with OTW, saying, “We were pleased to see that patients had experienced nice reductions in pain and improvements in function. Some of those changes were substantial and durable out to a year following a single injection.”

Dr. Clayman continued, “We have a lot more data to generate, but we view these preliminary data as encouraging.”

Today Flexion Therapeutics finds itself in a very positive position and the company has a lot to look forward to throughout this year. While discussing the future of Flexion Therapeutics with OTW, Dr. Clayman expressed excitement about the “growing momentum” with its lead commercial asset ZILRETTA and  the company’s plans to initiate a registration trial to investigate ZILRETTA in shoulder OA pain later this year.

He also expressed excitement about Flexion Therapeutics having both FX201 and FX301 in the product pipeline. Dr. Clayman told OTW, FX301 “is a completely novel peripheral nerve block for the treatment of postoperative pain in patients undergoing a variety of surgical procedures.”