Definium's LSD-based drug lowers anxiety in new late-stage trial, shares soar

Definium Therapeutics said its LSD-based treatment reduced symptoms of generalized anxiety disorder in a second successful late-stage study, sending shares soaring nearly 20% in premarket trading on Monday.

A single 100-microgram dose of DT120, a fast-dissolving tablet of lysergide, or LSD, reduced scores on an anxiety scale by 9.8 points after 12 weeks, compared with a 4.7-point decline for placebo, the company said.

Regulatory and investor enthusiasm for psychedelic-based therapies has helped Definium shares nearly triple this year. Psychedelic drugs can temporarily alter perception, mood and thinking.

DT120 had also significantly reduced anxiety symptoms in the first trial, the company had said in August.

CEO Robert Barrow said that having two studies answers “questions around the attribution of what's driving drug effect,” as the company looks for the U.S. FDA's approval in the first half of next year.

About a dozen programs have attempted approval for GAD in the last 20 years and have failed, he said.

GAD, characterized by persistent and excessive worry that can interfere with daily life, affects about 26 million U.S. adults and is commonly treated with antidepressants, anti-anxiety medicines and psychotherapy.

The 245 patients in the new trial received either 100 micrograms of DT120, a lower 50-microgram dose or placebo. The lower-dose arm was added to mitigate functional unblinding, a limitation of clinical trials where participants can accurately guess treatment assignments due to distinct side effects or unmistakable drug experiences.

Nonetheless, at both doses, patients were able to correctly guess when they were assigned to drug rather than placebo, Barrow said.

Higher efficacy on the 100-microgram dose versus the 50-microgram one, “gives us obviously an easier discussion (with regulators),” he said.