Itruvone · program
Itruvone for Major depressive disorder
- Fast Track
Itruvone (PH10) for major depressive disorder. A positive randomized, double-blind, placebo-controlled Phase 2A study (HAM-D-17 endpoint) was conducted in Mexico and published; a U.S. Phase 1 bridging safety study in healthy adults completed in 2023 with favorable safety/tolerability, enabling planned U.S. Phase 2B development as a non-systemic, stand-alone MDD treatment. FDA Fast Track designation granted December 2022. As of 2025, staged for potential U.S. Phase 2B (Vistagen or a strategic partner).
Development timeline
- Favorable safety/tolerability results from U.S. Phase 1 bridging study (single-center, randomized, double-blind, placebo-controlled, healthy adults; first dosed Jan 2023, last patient last visit Mar 2023) announced; no serious adverse events or AE discontinuations. Enables planned U.S. Phase 2B development. Program remains Phase 2 overall.↗
- FDA granted Fast Track designation for development of PH10 (itruvone) to treat major depressive disorder.↗
- metPositive Phase 2A study of PH10 (itruvone) in MDD: statistically significant rapid-onset antidepressant effect on HAM-D-17 vs placebo↗
- Option exerciseVistaGen exercises option for exclusive worldwide license to PH10 (itruvone) from Pherin↗
Readouts
- 2020-02-19ReportedFull resultsmet
Positive Phase 2A study of PH10 (itruvone) in MDD: statistically significant rapid-onset antidepressant effect on HAM-D-17 vs placebo ↗
Formulations
| Formulation | Route | Regimen | Pharmacokinetics |
|---|---|---|---|
| Itruvone intranasal spraynasal spray Microgram-level intranasal doses; Phase 2A studied 3.2 µg and 6.4 µg once daily for 8 weeks | Intranasal | Once daily | — |
Mechanism of action
Itruvone is a synthetic neuroactive 'pherine' (vomeropherine) delivered as an intranasal microgram-dose spray. Its proposed rapid-onset mechanism is non-systemic: it engages and activates chemosensory neurons in the nasal passages that connect to olfactory-amygdala neural circuits, increasing activity of the limbic-hypothalamic sympathetic nervous system and catecholamine release to produce antidepressant effects. Preclinical biodistribution work found radiolabeled [14C]PH10 essentially undetectable in the brain, blood, and plasma after intranasal dosing, supporting a peripheral (nasal-neuron) site of action with no measurable systemic exposure. No characterized systemic molecular receptor target has been published; the nasal chemosensory receptor mediating its effect remains uncharacterized.
| Target | Action | Affinity |
|---|---|---|
| Nasal chemosensory neuron receptor (uncharacterized)primary | Unknown | —ⓘ |
← Full Itruvone compound page (identity, identifiers, all indications)
Sources
- Vistagen Announces Closing of Pherin Pharmaceuticals Acquisition — VistaGen Therapeutics, Inc.
- VistaGen Announces Positive Results of Newly Published Exploratory Phase 2a Study of PH10 for Rapid-Onset Treatment of Major Depressive Disorder — VistaGen Therapeutics / PR Newswire
- Vistagen Announces Results of Successful U.S. Phase 1 Study of Itruvone (PH10), Enabling U.S. Phase 2B Development for Treatment of Major Depressive Disorder — Vistagen Therapeutics / Business Wire
- Vistagen Receives FDA Fast Track Designation for Development of PH10 to Treat Major Depressive Disorder — Vistagen Therapeutics / Business Wire
- Vistagen Reports New Preclinical Data Supporting Itruvone (PH10) Nasal Spray — VistaGen Therapeutics
- Vistagen Reports New Preclinical Data Supporting Itruvone (PH10) Nasal Spray's Potential Antidepressant Activity via Peripheral Nasal Neurons without Entry into the Brain — Vistagen Therapeutics / Business Wire
- VistaGen Therapeutics Acquires Worldwide Rights to Develop and Commercialize PH10, a First-in-Class Intranasally Administered Neuroactive Steroid with Rapid-onset Antidepressant Effects for Major Depressive Disorder — VistaGen Therapeutics, Inc. (GlobeNewswire)