Development of FLX-787 for ALS under Fast Track Designation —

BOSTON, MA, USA I August 1, 2017 I Flex Pharma, Inc. (NASDAQ: FLKS), a clinical-stage biotechnology company that is developing innovative and proprietary treatments for cramps and spasticity associated with severe neurological diseases such as amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) and peripheral neuropathies such as Charcot-Marie-Tooth (CMT), today announced that, under its open investigational new drug (IND) application, the Company has initiated a Phase 2 randomized, controlled, double-blinded, parallel design trial in the US, referred to as the COMMEND trial. The COMMEND trial will evaluate FLX-787, the Company’s co-activator of TRPA1 and TRPV1, in patients with motor neuron disease (MND), focused on ALS, who suffer from painful, debilitating cramps. The FDA has granted FLX-787 Fast Track designation for the treatment of severe muscle cramps associated with ALS. The Company expects to report topline results from this study in the middle of 2018. The Company also intends to initiate a Phase 2 clinical trial in CMT this quarter.

“Muscle cramps can have a severe impact on functional performance and quality of life for patients with motor neuron diseases like ALS,” indicated lead investigator Dr. Björn Oskarsson of the Mayo Clinic in Jacksonville, Florida. “Neurologists are often confronted with a situation where the patient experiences symptoms, and current treatments are either ineffective or have potentially limiting side effects. Flex Pharma’s FLX-787 may provide a better approach to this challenging problem.”

“The Fast Track designation for FLX-787 is a validation by FDA that cramps are a severe, unmet medical need in ALS,” commented Dr. William McVicar, Flex Pharma President and CEO. “While physicians treating ALS patients have come to understand how great an impact severe cramping – and the pain that attends it – can have on the lives of ALS patients, the lack of safe and effective and treatments has provided little impetus to focus on the problem. We are working hard to change this with FLX-787.”

About the COMMEND Clinical Trial

The COMMEND trial is a Phase 2 clinical trial designed to evaluate FLX-787 in patients with motor neuron disease (MND), focused on ALS, who suffer from cramps. This randomized, controlled, double-blinded, parallel design trial in the US will include a run-in period to establish a baseline in cramp frequency. Patients will then be randomized to 30 mg of FLX-787 administered three times a day, or control, for 28 days. Patients will be evaluated for changes in cramp frequency as the primary endpoint, with a number of secondary endpoints.

About Flex Pharma

Flex Pharma, Inc. is a clinical-stage biotechnology company that is developing innovative and proprietary treatments for cramps and spasticity associated with the severe neurological diseases of ALS, MS and peripheral neuropathies such as Charcot-Marie-Tooth (CMT). The Company’s lead candidate, FLX-787, is being developed under Fast Track designation for the treatment of severe muscle cramps associated with ALS. Flex Pharma was founded by National Academy of Science members Rod MacKinnon, M.D. (2003 Nobel Laureate), and Bruce Bean, Ph.D., recognized leaders in the fields of ion channels and neurobiology, along with Chair Christoph Westphal, M.D., Ph.D.

SOURCE: Flex Pharma