Benzinga | Mar 1, 2021 07:31AM EST

Flexion Therapeutics Announces FDA Clearance Of Investigational New Drug Application For FX301 In Post-Operative Pain

* FX301 combines NaV1.7 inhibitor (funapide) with a proprietary thermosensitive hydrogel to facilitate administration as a peripheral analgesic nerve block

* FX301 may provide 3 to 5 days of non-opioid pain relief while preserving motor function following musculoskeletal surgery

* Proof of concept Phase 1b clinical trial in patients undergoing bunionectomy expected to begin in the first half of 2021

BURLINGTON, Mass., March 01, 2021 (GLOBE NEWSWIRE) -- Flexion Therapeutics, Inc. (NASDAQ:FLXN) today announced the U.S. Food and Drug Administration (FDA) cleared the Investigational New Drug (IND) application for FX301, a locally administered NaV1.7 inhibitor known as funapide, formulated for extended-release in a thermosensitive hydrogel. The selective pharmacology of funapide holds the potential to provide effective non-opioid pain relief for at least 3 to 5 days, while preserving extremity motor function which is typically compromised by local anesthetic peripheral nerve block.

"The IND clearance represents a key milestone for Flexion as we continue to advance our pipeline of important product candidates aimed at alleviating pain and improving outcomes for millions of people confronting musculoskeletal conditions along their continuum of care," said Michael Clayman, MD, President and Chief Executive Officer of Flexion Therapeutics. "FX301 utilizes a proprietary formulation that was developed in our Innovation Lab and which converts from a liquid to a gel once it warms to body temperature following injection. We believe FX301 holds the unique potential to provide several days of meaningful post-operative pain relief as well as preserve the ability to ambulate and initiate rehabilitation following musculoskeletal surgery."

The FDA's clearance of the IND was supported by key preclinical data developed by Flexion and extensive clinical data associated with previous clinical trials investigating funapide in other indications. In a validated preclinical model of post-operative pain, FX301 administered as a peripheral nerve block demonstrated analgesic effect beginning at 1 hour post-dosing compared to placebo and significantly greater analgesic effect compared to liposomal bupivacaine at 36 hours post-dosing. Data from the study also indicated that treatment with FX301 did not significantly affect total walking distance in animals at 2 and 24 hours post-injection, whereas animals treated with liposomal bupivacaine experienced a significant reduction in total walking distance at those time points.

Flexion plans to initiate a Phase 1b proof of concept clinical trial of FX301 administered as a popliteal fossa block (a commonly used nerve block in foot and ankle-related surgeries) in patients undergoing bunionectomy and expects to treat the first patient in the first half of this year. Topline results from the trial are anticipated in late 2021.