A New York-based pharmaceutical company, Definium Therapeutics, announced Monday that a single dose of its experimental LSD-based pill dramatically reduced symptoms of major depression in patients enrolled in a late-stage clinical trial.
The company’s drug, known as DT120, helped patients score significantly lower on a standard depression measurement scale compared to those who received a placebo after six weeks — an 8.1 point difference that met the trial’s primary goal.
Results showed improvement as early as one week after patients took a single pill, with those on DT120 scoring 14.2 points better than the placebo group. At the 12-week mark, patients still showed gains of 7.3 points over the placebo group.
Analysts at Jefferies had previously noted in a client memo earlier this month that a placebo-adjusted improvement of 4 to 5 points at week six, with lasting effects, would be considered a strong outcome — a bar that DT120 appears to have cleared by a wide margin.
DT120 falls into a category of medications called classic psychedelics, which temporarily change how a person perceives the world, their mood, and their thinking. The drug is a pharmaceutical version of lysergide — commonly known as LSD — and works by stimulating serotonin receptors in the brain.
The announcement comes after U.S. President Donald Trump signed an executive order in April directing federal agencies to fast-track access to psychedelic-based medical research and treatment for serious mental health conditions.
The drug was reported to be well-tolerated by participants. According to the company, 99% of adverse events were mild to moderate and occurred mainly on the day the dose was taken. No serious safety concerns or increases in suicidal thoughts were reported.
The trial included 149 participants between the ages of 18 and 74, all diagnosed with major depressive disorder — a condition recognized as a leading cause of disability and death worldwide. The National Institutes of Health estimates that roughly 21 million adults in the United States have experienced at least one major depressive episode.
Definium said the positive results bring it a step closer to submitting the drug for FDA review. The company is also currently conducting a second late-stage clinical trial focused on depression.
