Olanzapine LAI (Weltruza) Receives FDA Approval for Schizophrenia

The US Food and Drug Administration (FDA) has approved olanzapine (Weltruza) extended-release injectable suspension, a once-monthly subcutaneous long-acting injectable (LAI), for adults with schizophrenia based on phase 3 SOLARIS data.¹

According to Teva, the approval makes olanzapine LAI is the first and only once-monthly subcutaneous olanzapine LAI and requires no loading doses, no oral supplementation, and no post-injection monitoring.¹ The existing intramuscular long-acting olanzapine formulation carries a Risk Evaluation and Mitigation Strategy (REMS) requiring administration in a certified health care facility and 3 hours of monitoring after each injection.²

Teva has framed the new formulation as a response to adherence challenges with daily oral olanzapine, which the company describes as the most widely prescribed atypical antipsychotic for schizophrenia.¹

“Olanzapine has been a trusted and foundational treatment option for people living with schizophrenia for more than 30 years, but adherence continues to be a major barrier to stability, particularly for those who rely on daily oral medications,” said Christoph Correll, MD, a clinical professor of psychiatry at the Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY. “By offering a subcutaneous long-acting injectable formulation with achievement of therapeutic blood levels without oral cotreatment, loading doses or booster injections, this new treatment option can help empower patients, support their care partners and provide clinicians with an important new tool to assist in managing this complex condition more effectively.”¹

More About the SOLARIS Trial

SOLARIS was a multinational, multicenter, randomized, double-blind, placebo-controlled phase 3 trial in patients aged 18 to 64 years with schizophrenia. During the 8-week period 1, 675 patients were randomized 1:1:1:1 to low-, medium-, or high-dose olanzapine LAI or placebo, administered once monthly by subcutaneous injection.¹ In the 48-week period 2, placebo completers were rerandomized equally across the 3 active doses, and patients already on active treatment remained on their assigned strength.¹

Period 2 assessed long-term safety and tolerability as a secondary objective, with end-of-treatment and follow-up visits 4 and 8 weeks after the final dose.¹

The primary end point was change in Positive and Negative Syndrome Scale (PANSS) total score, with Clinical Global Impression–Severity (CGI-S) and Personal and Social Performance (PSP) scale scores as key secondary measures.¹ Teva reported improvement in PANSS symptoms, a significant reduction in CGI-S illness severity, and improvement in PSP functioning with olanzapine LAI.¹

The approved doses of 318 mg, 425 mg, and 531 mg correspond to daily oral olanzapine doses of 10 mg, 15 mg, and 20 mg, respectively. Teva expects the product to become available in the US in the coming weeks.¹

Safety, PDSS Risk, and Long-Term Stabilization

All 3 doses were similarly tolerated in SOLARIS, with weight gain, somnolence, headache, constipation, and injection site reactions among the most common adverse events. Weight gain and metabolic changes, including clinically significant weight gain, were consistent with the systemic safety profile of oral olanzapine, according to Teva.

Discontinuations due to common adverse events occurred in 5% of olanzapine LAI recipients and 4% of placebo recipients.No cases of post-injection delirium/sedation syndrome (PDSS) were observed or confirmed across 3971 injections in SOLARIS.

Labeling still includes a PDSS warning, noting the syndrome has occurred with intramuscular extended-release olanzapine and its occurrence with subcutaneous dosing is unknown. Labeling also carries a boxed warning for increased mortality in elderly patients with dementia-related psychosis.¹

In post hoc analyses of the open-label period, more than half of participants achieved clinical stabilization, and more than 20% of those treated for 6 months or longer met remission criteria. Few patients reaching stabilization went on to relapse, Hughes reported.²

Olanzapine LAI uses SteadyTeq, a copolymer technology from Medincell designed for steady, sustained drug release.¹ The European Medicines Agency accepted a marketing authorization application for the agent in May 2026, and it is not yet approved in Europe.¹

References

1. Teva announces US Food and Drug Administration (FDA) approval of Weltruza (olanzapine) for extended-release injectable suspension, as the first and only once-monthly subcutaneous injectable olanzapine for adults with schizophrenia. October 9, 2026. Accessed October 9, 2026. https://www.tevapharm.com/news-and-media/latest-news/teva-announces-u.s.-food-and-drug-administration-fda-approval-of-weltruza-olanzapine-for-extended-re

2. Hughes E, Walters J. Post hoc SOLARIS data support stabilization and remission with subcutaneous olanzapine. Psychiatric Times. October 2, 2026. https://www.psychiatrictimes.com/view/post-hoc-solaris-data-support-stabilization-and-remission-with-subcutaneous-olanzapine