Sofinnova, NEA power autoimmune startup Polyneuron to A round

The co-founders of Polyneuron. (University of Basel)

Polyneuron Pharmaceuticals has raised CHF 22.5 million ($22.6 million) to run a phase 1 trial in a rare autoimmune disease. Sofinnova Partners and New Enterprise Associates co-led the investment in the startup on the strength of its technology for eliminating pathological autoantibodies.

Swiss startup Polyneuron spun out of the University of Basel in 2014 to advance drugs derived from a glycopolymer platform. The platform is designed to facilitate the creation of injectable glycopolymers that copy the part of an antigen recognized by the immune system. Polyneuron thinks these epitope mimics will selectively bind to and eliminate disease-causing antibodies.

Working with fairly small sums of money from backers including EVA Basel, Polyneuron has taken an asset derived from the platform deep into preclinical development. The potential of that drug and the broader platform enabled Polyneuron to attract a bigger sum from heavy hitter VCs.

Sofinnova and NEA have come on board to help Polyneuron take its lead candidate into a first-in-human clinical trial. The drug, PN-1007, is a treatment for anti-MAG peripheral neuropathy, a rare disease that manifests when the immune system turns against a glycoprotein involved in the maintenance of the peripheral nervous system. Sufferers can find it hard to walk.

Polyneuron designed PN-1007 to mimic natural HNK-1 carbohydrate epitope. In doing so, the Swiss biotech created a drug that preclinical tests suggest stops autoantibodies from binding to the natural HNK-1 carbohydrate on the glycoprotein at the root of anti-MAG peripheral neuropathy.

The approach is more targeted than those of existing treatments for the disease, which are limited to the off-label use of immunosuppressants. Like PN-1007, these treatments are intended to reduce levels of the disease-causing autoantibodies, but there is ample scope to improve on their selectivity and efficacy. 

While advancing PN-1007, Polyneuron will use another slice of the series A monies to move two of its other assets forward. Polyneuron has publicly discussed its work on candidates to treat multifocal motor neuropathy and enable organ and stem cell transplants with ABO-blood group incompatibility. Both programs are further back in preclinical development than PN-1007.