— FLX-787 Phase 2 Clinical Programs in ALS & CMT to Close —

— FLX-787 Clinical Evaluation of Dysphagia to Continue —

— Wedbush PacGrow Retained to Guide Assessment of Strategic Alternatives —

— Restructuring with Workforce Reduction —

BOSTON, MA, USA I June 13, 2018 I Flex Pharma, Inc. (NASDAQ: FLKS), a clinical-stage biotechnology company, today announced that the Company is ending its ongoing Phase 2 clinical trial investigations of FLX-787 in amyotrophic lateral sclerosis (ALS) and Charcot-Marie-Tooth (CMT) due to oral tolerability concerns observed in both studies, in a subset of patients being treated, with the oral disintegrating tablet formulation at 30 mg, taken three times a day.

“In the past few months we have reported positive efficacy data in two serious and distinctly different neurological diseases: multiple sclerosis (MS) and ALS. We believe that these clinical data demonstrate the clear potential of FLX-787 as a symptomatic therapy to reduce painful cramps and spasms in these patient populations,” stated Bill McVicar, Ph.D., President and CEO of Flex Pharma. “However, recent observations of oral intolerability at the current dose and formulation, in a subset of patients, in both studies, indicate that more formulation and dose-ranging studies are required, which is challenging for the Company based upon our current resources.”

The Company’s Board of Directors and its management are in alignment that the Company’s best path forward to preserve stockholder value is to focus its resources on assessing strategic alternatives, including the potential sale or merger of the Company. The Board has established a Strategic Committee that will work with management to oversee this process. Wedbush PacGrow has been engaged to act as the Company’s strategic financial advisor. There can be no assurance that this process will result in any such transaction and the Company does not intend to disclose additional details unless and until it has entered into a specific transaction.

The Company will continue to operate with a reduced internal team that will focus their efforts on assessing the potential of FLX-787 in dysphagia (difficulty swallowing) and operating the HOTSHOT consumer business while the strategic review is ongoing.

In connection with these decisions, Flex Pharma will restructure its organization to reduce costs, including reducing its workforce by approximately 60 percent. Most of these changes are anticipated to be completed by June 30, 2018. As a result, the Company expects to realize annualized cost savings beginning in the third quarter of 2018. The Company estimates that it will incur one-time costs of approximately $0.8 million to $1.1 million related to the restructuring plan.

About Flex Pharma

Flex Pharma, Inc. is a clinical-stage biotechnology company that is developing FLX-787 for dysphagia. 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 Christoph Westphal, M.D., Ph.D.

SOURCE: Flex Pharma