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In October, Pharnext reported positive results for a Phase III trial in humans of one of its drug combinations. The compound is PXT3003, a treatment for a neurodegenerative condition called Charcot-Marie-Tooth disease (CMT),

a rare disorder for which no cure has been found. The primary cause of CMT is duplication of a single gene, but a whole cascade of bad things ensues "downstream" from that mutation.

Schwann cells, which protect nerves, regress into stem cells that don't do their job. Axons in the nerves begin to die off. Muscles can't be controlled, and they shrink as a consequence.

According to Pharnext, its Phase III results (which have not yet been peer-reviewed) showed CMT not merely stabilizing under PXT3003 but also being reversed, as cells began regenerating.

Previous treatments, Cohen says, had managed only to slow patients' decline. Under PXT3003, patients showed statistically significant improvement on two measures of disability.

Based on those results, in February the U. S. Food and Drug Administration granted Pharnext "fast track" status for that therapy- an accelerated review process, awarded only when the agency thinks a drug demonstrates "superior effectiveness" in treating a serious disease.

It is, to be sure, only one hopeful step against one rare ailment. Still, technology has shortened Pharnext's path in ways with promising long-term implications, shaving years off the drug-design timeline.

Preclinical testing and clinical trials generally take eight to 10 years, and developing a novel drug completely from scratch can add seven years to the process, sometimes much more.

In the case of PXT3003, in contrast, A. I. helped Pharnext select three existing drugs to repurpose: baclofen, a muscle relaxant; naltrexone, used to treat opioid dependence; and sorbitol, a glucose reduction used as a laxative.

Because the drugs were already in use, Pharnext could skip the Phase I trials normally required to ensure their safety-and eliminate the "build from scratch" stage. FDA fast-tracking increases the odds that PXT3003 could be on the market as soon as 2020-and it's only one of Pharnext's many projects.