Topiramate as a Disease Altering Therapy for CSPN
Cryptogenic sensory peripheral neuropathy (CSPN) affects 5-10% of Americans. CSPN causes progressive injury to the very longest nerves of the body resulting in pain, loss of balance, and fall-related injury. There is no FDA approved treatment for CSPN or its symptoms. Our previous research has found that CSPN can be detected and followed by examining nerves that reach to the skin using a small punch biopsy of the skin outer layers. These cutaneous nerves can be injured by high blood glucose, obesity and high triglycerides, but have the potential to regrow in response to treatments that improve these metabolic conditions. Topiramate is an FDA approved medication for seizures, migraine headaches and medical weight loss (in combination with phentermine). It causes weight loss and improves the body’s sensitivity to insulin. It also reduces the activity of sodium channels (or pores) in the nerves. Both of these effects are expected to improve CSPN. NN108 will randomize participants with CSPN to oral topiramate or a matched placebo (“sugar pill”) for two years to see if treatment reduces loss of nerve fibers in the skin and also improves patient quality of life.
The objective of NN108 is to determine if oral topiramate slows progression of CSPN using intraepidermal never fiber density (IENFD) as the primary measure of axonal loss and Norfolk QOL-DN.
NN108 is supported by NINDS (U01 NS095388).