Flupirtine for Fibromyalgia
Synthetic Biologics has partnered the development of flupirtine, a centrally-acting investigational oral drug, for the treatment of fibromyalgia syndrome with Meda AB. Flupirtine is a selective neuronal potassium channel opener that also has NMDA receptor antagonist properties. Flupirtine is a non-opioid, non-NSAID, non-steroidal, analgesic. Preclinical data and clinical experience suggest that flupirtine should also be effective for neuropathic pain since it acts in the central nervous system via a mechanism of action distinguishable from most marketed analgesics. Flupirtine is especially attractive because it operates through non-opiate pain pathways, exhibits no known abuse potential, and lacks withdrawal effects. In addition, no tolerance to its antinocioceptive effects has been observed. One common link between neuroprotection, nocioception and flupirtine may be the N-methyl-D-aspartic acid glutamate system, a major receptor subtype for the excitotoxic neurotransmitter, glutamate. Flupirtine has strong inhibitory actions on N-methyl-D-aspartic acid-mediated neurotransmission. Flupirtine was originally developed by Asta Medica (subsequently acquired by Meda AB) and has been approved and is marketed by Meda AB in Europe since 1984, as well as other countries, for the treatment of pain. It has never been approved by the FDA for any indication.
On May 6, 2010, Synthetic Biologics and Pipex, its wholly owned subsidiary, entered into a sublicense agreement with Meda AB, a multi-billion dollar international pharmaceutical company, pursuant to which Meda AB assumed all future development costs and may commercialize flupirtine for fibromyalgia in the United States. As consideration for such sublicense, Synthetic Biologics received an up-front payment of $2.5 million and is entitled to milestone payments of $5 million upon the FDA’s acceptance of the New Drug Application (NDA) for flupirtine for fibromyalgia and $10 million upon FDA approval of such NDA. Pursuant to the sublicense agreement, Synthetic Biologics will also receive a 7% royalty on net sales of flupirtine for fibromyalgia in the United States, Canada and Japan, with such royalties being shared equally with Synthetic Biologic’s licensor, McLean Hospital, a Harvard teaching hospital.
Fibromyalgia is a chronic and debilitating condition characterized by widespread pain and stiffness throughout the body, often accompanied by severe fatigue, insomnia and mood symptoms. According to the National Fibromyalgia Association, fibromyalgia affects an estimated 3-6% of the population worldwide, including an estimated 10 million patients in the U.S.
There are presently three FDA products approved for this indication in the United States – Lyrica®, Cymbalta® and Savella®. Flupirtine is differentiated from these products in that it employs a unique mode of action.