Vanda soars after FDA reviewer urges OK for sleep disorder drug

FDA drug reviewer Devanand Jillapalli left little to the imagination when he summed up Vanda Pharmaceuticals' case for tasimelteon. The drug--designed to correct the circadian rhythms of the blind to ensure normal sleep patterns--worked as billed in the late-stage program for non-24 hour disorder, he wrote, and, given that there were no serious adverse events to consider, ought to be endorsed during an upcoming expert panel review and then approved by the agency.

"I recommend approval," was Jillapalli's first line, and things only got better for Vanda ($VNDA) after that. Looking over the trial data, the FDA review concluded that "these results support the use of tasimelteon in the treatment of circadian rhythm disorders in patients with Non-24 Hour Disorder who are totally blind."

FDA internal drug reviews are usually drawn with a very skeptical eye, looking to raise the most serious questions for the panel to consider. The unusually unvarnished recommendation quickly caught the attention of Wall Street, where Vanda's shares immediately shot up more than 90%.

The recommendation was all the more remarkable as Vanda and the FDA did not agree ahead of time on a primary endpoint for the study. But they did subsequently agree to consider nighttime sleep and daytime naps as a likely indicator of efficacy, focusing on periods when patient symptoms of the disorder are at their worst.

By that measure, the late-stage work was cleared as a success.

"Tasimelteon numerically improves nighttime sleep and decreases daytime nap duration," wrote Jillapalli. "Tasimelteon significantly improves the timing of sleep relative to the desired bedtime. Tasimelteon is significantly efficacious in treating Non-24 Hour Disorder as measured by clinically meaningful improvement in the Non-24 Clinical Response Scale."

The panel takes up its review on Thursday. The drug, which will be marketed as Hetlioz, faces a PDUFA date at the end of January.

- read the FDA review (PDF)