Alto Neuroscience, Inc. announced the initiation of a Phase 2 double-blind, placebo-controlled study of its transdermal formulation of ALTO-101, a novel PDE4 inhibitor in development for the treatment of cognitive impairment associated with schizophrenia (CIAS). Alto expects to report top-line data from the Phase 2 study in the second half of 2025. Alto recently completed a Phase 1 study of ALTO-101 in healthy adults, demonstrating positive effects on cognition and electroencephalography (EEG) measures relevant to cognitive function.

Alto?s novel transdermal formulation of ALTO-101 exhibited greater systemic drug exposure than orally administered ALTO-101 while also demonstrating a reduction in typical class-related adverse events. The Phase 2 study announced on June 20, 2024 consists of a cross-over double-blind, placebo-controlled, dose-escalating treatment with ALTO-101 and placebo in patients with CIAS. Alto expects to enroll approximately 70 adult participants between 21-55 years old with schizophrenia and a demonstrable level of cognitive impairment.

Alto will evaluate the effects of ALTO-101 on EEG markers relevant to cognitive function and will also explore its effects on cognitive performance. The primary outcome in the study is the effect of ALTO-101 on theta band activity as measured using EEG at the end of each dose period. Alto recently presented data at the Society of Biological Psychiatry (SOBP) Annual Meeting demonstrating that theta band activity has both the greatest correlation with cognitive function in patients with schizophrenia among a comprehensive set of EEG measures as well as greatest case-control sensitivity.

The findings on these measures, which were prospectively replicated, support the suitability of the primary outcome measure being evaluated in the present study to demonstrate robust proof-of-concept of ALTO-101 as a potential treatment for CIAS.