Why did the MapLight Therapeutics (NASDAQ:MPLT) autism trial fail to meet its primary endpoint?

MapLight Therapeutics (NASDAQ:MPLT) announced that its Phase 2 IRIS trial did not meet its primary endpoint because ML-004 did not demonstrate significant improvement in caregiver-reported social communication scores over 12 weeks. The study evaluated a total of 161 combined adult and adolescent patients.

What specific subgroup benefits were discovered during the MapLight Therapeutics (NASDAQ:MPLT) study?

A prespecified analysis of 20 adolescent patients aged 12 to 17 with moderate or higher baseline irritability showed notable improvement. In this specific group, ML-004 achieved a 9.58-point reduction in irritability measures compared to the placebo group.

How did ML-004 affect patient safety and weight metrics for MapLight Therapeutics (NASDAQ:MPLT)?

MapLight Therapeutics (NASDAQ:MPLT) reported that ML-004 was well-tolerated with zero severe or serious adverse events recorded in the active treatment group. Additionally, the average patient weight gain over the course of the study was lower with ML-004 than with the placebo.

What are the next regulatory steps for MapLight Therapeutics (NASDAQ:MPLT) regarding ML-004?

MapLight Therapeutics (NASDAQ:MPLT) plans to arrange an End-of-Phase 2 meeting with the United States Food and Drug Administration. The company stated that this meeting will focus on reviewing the mixed clinical findings to map out a prospective development path.

When does MapLight Therapeutics (NASDAQ:MPLT) expect to release its next major pipeline data?

MapLight Therapeutics (NASDAQ:MPLT) forecasts the release of topline data from its separate Phase 2 trial for schizophrenia by mid-August 2026. This upcoming program will evaluate the clinical efficacy of its pipeline candidate ML-007C-MA.

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MapLight autism trial misses endpoint for 161 patients

Written by Isaac FrancisPublished Jun 22, 2026, 11:56 AM

MapLight announced that its Phase 2 trial of ML-004 for autism did not meet its primary endpoint.
A prespecified adolescent subgroup demonstrated a statistically significant reduction in irritability scores.
The company remains funded to advance its upcoming pipeline data in schizophrenia later this quarter.

MapLight (NASDAQ:MPLT) announced that its Phase 2 autism trial of 161 patients missed its primary efficacy endpoint.

The study failed to improve caregiver-reported social communication scores, contrasting with positive behavioral responses found in a subgroup.

A prespecified analysis of 20 adolescent patients demonstrated an improved 9.58-point reduction in irritability measures versus a placebo.

Clinical data showed that the drug was well-tolerated with lower weight gain and zero severe or serious adverse events.

Following the announcement, MapLight's share price was down at $25.92.

The biotechnology firm plans to arrange an End-of-Phase 2 regulatory meeting with the FDA to review these findings.

The company expects to report separate Phase 2 schizophrenia data from its pipeline program by mid-August 2026.

MapLight autism trial misses endpoint for 161 patients

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