What if relief from relentless worry did not mean another pill every morning, but one carefully supervised session that keeps helping for months.
That is the promise and the big question behind a new clinical trial of MM120, an oral formulation of lysergide better known as LSD, for generalized anxiety disorder.
In a phase 2b study published in the Journal of the American Medical Association, a single dose of MM120 significantly reduced anxiety symptoms in 198 adults with moderate to severe generalized anxiety disorder, compared with placebo. The benefits were strongest at 100 micrograms and, for many participants, were still present twelve weeks later.
For people who live with a constant knot in the stomach and racing thoughts on the commute or while trying to fall asleep, that sounds almost unreal. Today, treatment usually means long courses of antidepressants, anti-anxiety drugs such as benzodiazepines, and psychotherapy. Yet nearly half of patients do not get enough relief and generalized anxiety disorder affects about 3% of adults in the United States.
How the MM120 trial worked
The trial enrolled adults aged 18 to 74 who had a primary diagnosis of generalized anxiety disorder and scores of at least 20 on the Hamilton Anxiety Rating Scale, a clinician scale that runs from zero to 56 and labels scores of 24 or more as severe anxiety.
Participants were randomly assigned to receive a single supervised session with MM120 at one of four doses, 25, 50, 100 or 200 micrograms, or a matching placebo.
There was no trial-related psychotherapy before or after dosing, which is a key difference from many earlier psychedelic studies that bundled medication with hours of therapy.
At four weeks, those who received 100 or 200 micrograms had a statistically-significant greater drop in Hamilton scores than the placebo group. On average, the advantage was about five to six points, which is above the threshold researchers consider a meaningful clinical change.
A more detailed analysis in secondary results showed that people on the 100 microgram dose had roughly a seven point greater reduction than placebo and that many kept improving through week twelve. Around 65% met criteria for clinical response and nearly half were in remission three months after that single session.
Put simply, a sizable share of participants moved from the “markedly ill” range to ratings closer to “borderline ill” or better on global clinician scales.
Intense experiences and familiar side effects
This was not a microdose experiment. MM120 produced the vivid altered perceptions and emotional intensity long associated with LSD. Visual changes such as illusions and hallucinations were the most common side effects and appeared in nearly every participant who received the highest dose.
Even at 100 micrograms, more than nine in ten participants reported some visual effects. Nausea and headache were also frequent and became more common as the dose went up.
According to the trial report, almost all adverse events happened on the dosing day and most had resolved by the end of that monitored session. Regulators will still want to see how often more serious reactions such as panic or prolonged distress occur in larger groups, especially once studies move beyond highly-selected volunteers.
A comeback for a controversial molecule
Lysergide is a semisynthetic psychedelic molecule and modern LSD was first derived from compounds in ergot fungus that grows on rye. Research into its therapeutic use burst into life in the 1950s and 60s, then collapsed after the drug was classified as a Schedule 1 substance in the United States, a category that claims no accepted medical use and high potential for abuse.
In recent years, psychedelics have made a cautious return to mainstream science. The United States Food and Drug Administration has already granted special “breakthrough therapy” status to psilocybin and MDMA based treatments and now to the MM120 program for generalized anxiety disorder, signaling that early data look promising enough to justify faster regulatory guidance.
Not everyone is ready to declare victory. External experts note that many participants could tell whether they had received LSD, which weakens the traditional blind in a randomized trial. Others point out that the paper does not give much detail on how volunteers were prepared for the experience or supported afterward, even though a difficult session can be psychologically demanding.
As researcher Frederick Barrett put it, this work is a clear step toward reviving old LSD research with modern standards, but it still leaves open questions about how best to integrate such powerful experiences into ongoing care.
What people with anxiety should keep in mind
For the most part, the new findings suggest that a single, carefully-managed LSD-based session may offer longer-lasting relief than many expected, at least for some people with severe generalized anxiety.
At the same time, experts emphasize that MM120 is still an experimental drug in midstage testing. MindMed is now running larger phase 3 trials that will follow patients longer and explore how often retreatment might be needed.
Outside of clinical research, LSD remains illegal in many countries and street products can vary widely in strength and purity. Self medicating with unregulated psychedelics, stopping prescribed medication without supervision, or trying to recreate a trial setting at home carries real risks.
For anyone struggling with anxiety that will not let up, the practical takeaway is that new options may be on the way, but for now the safest path still runs through licensed health professionals who can explain which treatments are available and which are not.
The study was published on JAMA Network.
