SOLARIS Protocol: A Phase 3, Randomized, Double-Blind, Placebo-Controlled Safety and Efficacy Trial of TV-44749 for Subcutaneous Use (Olanzapine for Extended-Release Injectable Suspension Use) in Adults With Schizophrenia

This work was sponsored by Teva Branded Pharmaceutical Products R&D, Inc. Background: Among patients with schizophrenia, nonadherence to oral antipsychotics increases relapse risk. Adherence may be improved with long-acting injectable (LAI) antipsychotics. Intramuscular LAI olanzapine is indicated for adults with schizophrenia, but clinical use is limited by the associated risk for post-injection delirium/sedation syndrome (PDSS). Methods: The Subcutaneous OLAnzapine extended-Release Injection Study (SOLARIS; NCT05693935) is an ongoing phase 3 study designed to assess the efficacy, safety, and tolerability of TV-44749, an investigational long-acting subcutaneous antipsychotic (LASCA) that combines olanzapine and an innovative, copolymer-based drug delivery technology in an extended-release injectable suspension. SOLARIS is designed with an 8-week, randomized, double-blind, placebo-controlled period followed by an up-to-48–week open-label safety period. Adults with schizophrenia with relapse within ≤8 weeks before screening who would benefit from hospitalization may be eligible. Patients are randomized 1:1:1:1 to receive once-monthly TV-44749 (low, medium, or high dose) or placebo. TV-44749 arms will be compared with placebo (overall α=0.05). After 8 weeks, the placebo group are rerandomized 1:1:1 to join the 3 TV-44749 groups. Results: The primary endpoint is change from baseline to week 8 in Positive and Negative Syndrome Scale (PANSS). α-controlled secondary efficacy endpoints include change from baseline to week 8 in Clinical Global Impression-Severity (CGI-S) and Personal and Social Performance Scale (PSP). Secondary endpoints include safety and tolerability, including absence of PDSS, and additional time points for efficacy assessments. Conclusions: When complete, this study will provide efficacy and safety data for multiple doses of once-monthly TV-44749, a LASCA for treatment of schizophrenia in adults.