AtaiBeckley Inc. announced peer-reviewed Phase 2a results demonstrating that a single intranasal dose of BPL-003 (mebufotenin benzoate) achieved rapid and sustained reductions in depression symptoms from baseline in participants with treatment-resistant depression who remained on stable SSRI therapy. A 66.7% antidepressant response rate was observed at Day 2 in both the 10 mg cohort (n=6) and 12 mg cohort (n=6), with 83% of participants in the 10 mg cohort and 66.7% of participants in the 12 mg cohort maintaining a response at Week 12. BPL-003 was generally well tolerated with no serious adverse events reported, and participants achieved mean discharge approximately 100 minutes post-dose.
The 12-week, open-label study enrolled 12 adults aged 18 to 75 years with moderate-to-severe major depressive disorder and treatment-resistant depression. All participants had failed at least two prior antidepressants and remained on a stable dose of one of four SSRIs—citalopram, escitalopram, sertraline or fluoxetine—throughout the study. Six participants received a single intranasal 10 mg dose of BPL-003 and six received a single intranasal 12 mg dose. This publication represents Part 2 of a four-part Phase 2a open-label study. Data from Part 1, published in March 2026, reported a mean depression score reduction by Day 2, sustained through 12 weeks. Topline data from Part 3, announced in September 2025, showed that a second dose of BPL-003 at Week 2 has the potential to induce additional reductions in depression scores.
BPL-003 received FDA Breakthrough Therapy Designation in October 2025. Phase 3 studies are on track to initiate in Q2 2026. Treatment-resistant depression affects an estimated 30% of the nearly 300 million people living with depression globally. BPL-003 is a patent-protected intranasal formulation administered via nasal spray, designed to deliver rapid and durable effects from a single dose with a short psychedelic duration.
This article is an AI-assisted summary. All facts and figures are drawn from the original report: https://www.benzinga.com/pressreleases/26/04/g51697974/ataibeckleys-bpl-003-shows-rapid-durable-antidepressant-response-in-treatment-resistant-depression