Single-dose DT402 treatment for adults with autism

An Open-label Study Evaluating DT402 in Adults With Autism Spectrum Disorder

Phase 2 Interventional Definium Therapeutics US, Inc. · NCT07303907

This open-label test will see if a single dose of DT402 improves social communication in adults with autism.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years to 65 Years
SexAll
SponsorDefinium Therapeutics US, Inc. Industry-sponsored
Locations1 site (New York, New York)
Trial IDNCT07303907 on ClinicalTrials.gov

What this trial studies

This single-center, open-label Phase 2A study will enroll about 20 adults aged 18–65 with diagnosed autism spectrum disorder who meet a threshold of social impairment on the SRS-2. Participants will receive a single administration of DT402 (the R‑enantiomer of MDMA) and will be followed for safety and changes in social and communication measures. Key exclusions include first-degree relatives with psychosis or bipolar disorder, current substance use disorder (excluding nicotine and caffeine), significant eye abnormalities that interfere with eye tracking, and any unstable medical illness. The study is intended to collect preliminary safety data and early signals of effect to guide larger controlled trials.

Who should consider this trial

Good fit: Adults 18–65 with a confirmed ASD diagnosis and clinically significant social deficits (SRS-2 ≥66) who do not have current substance use disorder, a first-degree relative with psychosis or bipolar disorder, significant eye problems, or unstable medical conditions are the intended participants.

Not a fit: People with psychotic or bipolar disorder in first-degree relatives, current alcohol or substance use disorder, significant eye issues, unstable illnesses, or those outside the 18–65 age range are unlikely to qualify or receive benefit from this protocol.

Why it matters

Potential benefit: If successful, DT402 could improve social communication and related functioning for some adults with ASD.

How similar studies have performed: MDMA-assisted approaches have shown promising results in PTSD, but using DT402 (the R‑enantiomer of MDMA) in adults with ASD is largely novel and untested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Diagnosis of ASD per records as confirmed by standard semi-structured interview for Autism diagnosis (eg, Autism Diagnostic Observation Schedule-Second Edition)
2. Male or Female aged 18 to 65
3. Presents with clinically significant deficits in socialization and communication as determined by Social Responsiveness Scales (SRS-2) ≥66

Exclusion Criteria:

1. Has uncorrected abnormalities in eye movement, alignment, or acuity or atypical eye features that could interfere with eye tracking
2. First degree relative with or lifetime history of a psychotic disorder or bipolar disorder
3. Current diagnosis of alcohol or substance use disorder (excluding nicotine and caffeine)
4. Any clinically significant unstable illness

Where this trial is running

New York, New York

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Autism Spectrum DisorderASD
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.