Rapport pulls forward RAP-219 bipolar mania readout to Q4 2026
Rapport now expects topline YMRS data from its placebo-controlled Phase 2 trial months earlier than its prior 1H 2027 guidance, testing a mechanism with no direct comparator in bipolar mania.
Executive Summary
- Rapport Therapeutics now expects topline results from its Phase 2 bipolar mania trial earlier than previously guided, compressing the visibility window into the fourth quarter.
- The trial's placebo-controlled design and single primary endpoint will produce a clean read on whether RAP-219 reduces manic symptoms, the first psychiatric efficacy signal for a drug developed mainly in epilepsy.
- No competitor trial in bipolar mania shares RAP-219's mechanism, leaving this readout without a direct precedent to benchmark against and placing the interpretive weight entirely on the trial's own data.
- Recruitment and enrollment changes tracked as routine registry housekeeping rather than signs of strain, with the trial still actively enrolling toward its raised target.
The catalyst
Rapport disclosed the accelerated timeline in its first-quarter 2026 business update, stating that topline results for RAP-219 in bipolar mania are now expected in the fourth quarter of 2026, ahead of previous first-half-2027 guidance. The trial, registered as NCT07046494, is a randomized, placebo-controlled Phase 2 study testing RAP-219 against placebo in adults with Bipolar I Disorder, using the Young Mania Rating Scale (YMRS) as its single primary endpoint. The study has a two-arm design, one experimental arm and one placebo comparator arm, and enrolls adults with a documented history of at least one prior manic episode within five years of screening. Rapport+1Rapport Therapeutics Reports First Quarter 2026 Financials and Provides Business UpdateMay 7, 2026Study Evaluating the Efficacy and Safety of RAP-219 in Adult Participants With Bipolar I DisorderNCT07046494
Probability of SuccessBased on the AppliedXL Probability of Success model. For more information about the methodology, read the research here.
Trial status
The trial has been Recruiting since August 2025, when it moved out of Not-yet-recruiting status, and it lists a start date of July 25, 2025. Its primary completion date now stands at September 1, 2026, having moved one month earlier from an October 2026 estimate in a registry update filed May 12, 2026, the same day the anticipated enrollment target rose from 224 to 250 patients. Both changes fall within the range the underlying operational model treats as routine: the enrollment revision registers as a 0% jump against the model's change threshold of 20% or more, and the completion date moved earlier, not later. Neither change signals distress; together with the accelerated readout guidance, they point to a program executing on or ahead of its own timeline. NCT07046494Study Evaluating the Efficacy and Safety of RAP-219 in Adult Participants With Bipolar I DisorderNCT07046494
What the endpoint will test
The primary endpoint, YMRS change from baseline, is a standard manic-symptom severity measure in bipolar trials, and secondary endpoints cover cardiovascular and safety measures including QTc interval, blood pressure, and treatment-emergent adverse events. As a placebo-controlled, randomized Phase 2 design with a single primary endpoint, the trial is structured to produce a decision-grade efficacy signal rather than an exploratory or safety-only read. The result will show whether RAP-219, a drug whose most advanced clinical data come from focal onset seizures, can also reduce manic symptoms against placebo, a mechanism-agnostic test of whether its epilepsy-derived pharmacology translates to a psychiatric indication. NCT07046494Study Evaluating the Efficacy and Safety of RAP-219 in Adult Participants With Bipolar I DisorderNCT07046494
A field without a direct comparator
No trial in the bipolar mania competitive set shares RAP-219's mechanism or target: comparator programs from Xenon Pharmaceuticals, Bristol-Myers Squibb, AbbVie, Neurocrine Biosciences, LB Pharmaceuticals, and Intra-Cellular Therapies test dopamine, serotonin, potassium-channel, or other distinct mechanisms in the same broad indication family, but none run against the same molecular target. That leaves RAP-219's bipolar mania program without a mechanistically matched precedent to benchmark its result against; the readout will stand on its own data rather than replicate or diverge from an established class result. Rapport's broader RAP-219 program has already produced positive Phase 2a follow-up data in focal onset seizures, including a 90% median reduction in clinical seizures over baseline in weeks 9-12, presented at the American Academy of Neurology meeting in April 2026. That epilepsy result does not predict the bipolar mania outcome, but it establishes that the same molecule has produced a measurable clinical effect in at least one indication, which is the backdrop against which the psychiatric readout will be read. RapportRapport Therapeutics Reports First Quarter 2026 Financials and Provides Business UpdateMay 7, 2026
This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.