Ex-Merck Serono team bags €8.7M for PhI Parkinson's program

Prexton Therapeutics, the first company to emerge from the €30 million ($34 million) biotech-creation program Merck Serono set up amid the shuttering of its Geneva R&D center, has closed a Series A round. The €8.7 million will allow Prexton to advance its Parkinson's disease candidate into the clinic.

Geneva, Switzerland-based Prexton picked up the asset from Domain Therapeutics--which was working on the program with German Merck--early in 2013. By then, Merck Serono had given Prexton €2.1 million in seed funding and dropped its Parkinson's program, freeing the startup to license the science from Domain. Over the past two years, the ex-Merck Serono double act that lead Prexton have picked out a lead candidate that is expected to penetrate and persist in the brain and run in vivo tests, culminating in them reaching a point at which more money is needed to advance.

Prexton Therapeutics CEO François Conquet

Sunstone Capital and Ysios Capital stepped in to co-lead the round, which also attracted financing from Merck Serono's venture capital unit. The cash will take Prexton up to the point at which it has Phase I data, which is penciled in for the third quarter of 2016. CEO François Conquet told FierceBiotech the exact timing will depend in part on the design of the Phase I trial, which is still being discussed. Prexton is currently running long-term toxicology tests and plans to file its paperwork for the Phase I trial toward the end of this year.

The trial will mark the next phase of Conquet's long-running interest in metabotropic glutamate receptors (mGluR). Conquet has worked on Parkinson's and other mGluR-related indications since his decade-long stint at GlaxoSmithKline ($GSK) in the 1990s. In the early 2000s, Conquet founded Addex Therapeutics (SIX:ADXN) to pursue his interest in the potential for a mGluR5 antagonist to treat cocaine dependence. Addex has been through more downs than ups over the past decade--Merck ($MRK) handed back a mGluR4 Parkinson's drug in 2011--but Conquet still believes in the science.

Prexton, like Addex before it, is pursuing the idea that mGluR4 is a better target for Parkinson's than the dopaminergic pathways that have dominated treatment of the disease to date. As Parkinson's progresses, dopamine-producing nerve cells die, making drugs progressively less effective. Focusing on a different pathway may allow the effect of the treatment to persist for longer. Conquet thinks it could be decades before we fully understand the mechanisms that underpin Parkinson's, but in the meantime it will be possible to improve the treatment of the disease.

"We're not trying to cure the disease, we just want to treat the symptoms," Conquet said.

- read the release (PDF)