FDA approves Teva’s WELTRUZA, the first once-monthly subcutaneous olanzapine injection for adults with schizophrenia, supported by Phase 3 SOLARIS data.
Written By: Kalyani Boharapi,
M.Pharm (Reg. Affairs)
Reviewed By: Pharmacally Editorial Team
Teva Pharmaceuticals announced on October 9, 2026, that the U.S. Food and Drug Administration (FDA) had approved WELTRUZA™ (olanzapine) extended-release injectable suspension for the treatment of schizophrenia in adults. The product is the first and only once-monthly subcutaneous long-acting injectable formulation of olanzapine approved for this indication in the United States. It does not require loading doses, oral supplementation or post-injection monitoring.
The approval is supported by results from the Phase 3 SOLARIS trial (NCT05693935), which demonstrated improvements in schizophrenia symptoms, illness severity, and personal and social functioning.
Phase 3 SOLARIS Trial Demonstrated Clinical Improvements
The multinational, multicentre, randomised, double-blind, placebo-controlled SOLARIS trial evaluated the efficacy, safety and tolerability of once-monthly subcutaneous olanzapine in adults aged 18–64 years with schizophrenia.
The first eight-week period enrolled 675 participants, randomised in a 1:1:1:1 ratio to receive low-, medium- or high-dose WELTRUZA or placebo. During the subsequent 48-week period, participants initially assigned to placebo were re-randomised equally to the three active-dose groups, while those receiving WELTRUZA continued their assigned doses.
The primary endpoint was the change in the Positive and Negative Syndrome Scale (PANSS) total score. Key secondary endpoints included the Clinical Global Impression–Severity (CGI-S) scale and Personal and Social Performance (PSP) scale.
Previously reported Week 8 results showed statistically significant improvements in PANSS scores compared with placebo across all three dose groups. The mean differences were −9.71 points for the 531 mg dose, −11.25 points for the 425 mg dose and −9.69 points for the 318 mg dose, with all comparisons reporting P<0.0001.
The trial also demonstrated improvements in CGI-S scores, with between-group differences of −0.47, −0.61 and −0.53 points for the high-, medium- and low-dose groups, respectively. PSP scores improved by 4.93, 3.15 and 4.63 points, respectively, compared with placebo. All reported secondary endpoint comparisons were statistically significant.
These numerical results were disclosed in earlier company reports; the October 9 approval announcement summarised the clinical findings without repeating the effect sizes.
Monthly Dosing and Administration
WELTRUZA will be available in the United States in three once-monthly subcutaneous strengths: 318 mg, 425 mg and 531 mg. These strengths correspond to daily oral olanzapine doses of 10 mg, 15 mg and 20 mg, respectively.
The formulation uses SteadyTeq™, a proprietary copolymer technology developed by Medincell to provide controlled, sustained release of olanzapine.
Olanzapine is an established atypical antipsychotic used to treat schizophrenia. However, maintaining long-term treatment adherence can be challenging with daily oral medication, potentially contributing to symptom instability and relapse. WELTRUZA offers a long-acting injectable alternative without the need for oral supplementation, loading doses or booster injections.
Safety and Tolerability Findings
In SOLARIS, all three WELTRUZA doses showed similar tolerability. The most commonly reported adverse events included increased weight, somnolence, headache, constipation and injection-site reactions. Weight gain and metabolic changes, including clinically significant weight gain, were consistent with the established systemic safety profile of oral olanzapine.
Discontinuations due to common adverse events occurred in 5% of WELTRUZA-treated participants and 4% of placebo-treated participants.
The prescribing information includes a warning about increased mortality in elderly patients with dementia-related psychosis; WELTRUZA is not approved for this population. Other important risks include hyperglycaemia and diabetes, dyslipidaemia, tardive dyskinesia, orthostatic hypotension, seizures, neuroleptic malignant syndrome and drug reaction with eosinophilia and systemic symptoms (DRESS).
Post-injection delirium/sedation syndrome (PDSS) has been reported with another extended-release intramuscular olanzapine formulation. Its occurrence with subcutaneous WELTRUZA remains unknown. Patients and healthcare professionals should consult the approved prescribing information for the complete safety profile and precautions.
European Regulatory Review
In May 2026, the European Medicines Agency (EMA) accepted the marketing authorisation application for olanzapine long-acting injectable, designated TEV-’749, for schizophrenia in adults. The application is supported by the clinical development programme, including SOLARIS. The product has not yet received EMA approval.
About Schizophrenia
Schizophrenia is a chronic mental disorder that affects thinking, emotions and behaviour. Symptoms may include delusions, hallucinations, disorganised speech or behaviour, and impaired cognitive function. Relapses can require emergency psychiatric care or hospitalisation, while difficulties maintaining treatment can contribute to worsening disease outcomes.
Teva estimates that approximately 2.1 million people in the United States are diagnosed with schizophrenia. WELTRUZA introduces a monthly subcutaneous formulation of an established antipsychotic, offering an additional treatment option for adults with the condition.
References
Teva Announces U.S. 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, Teva Pharmaceuticals, 09 October 2026
A Randomized, Double-Blind, Placebo-Controlled Study with an Open-Label, Long-Term Safety Phase to Evaluate the Efficacy and Safety of TV-44749 in Adults with Schizophrenia (SOLARIS), ClinicalTrials.gov ID NCT05693935
About the Writer
Kalyani Boharapi (LinkedIn) is a pharmacy professional and healthcare writer currently pursuing an M.Pharm in Regulatory Affairs at Dr. D. Y. Patil College of Pharmacy, with interests in pharmaceutical regulations, drug development, and healthcare innovation. She has academic exposure to dossier preparation, scientific writing, and regulatory documentation. Kalyani has also completed certification courses in Generative AI, AI in Pharma, and Bioinformatics, and actively participates in pharmaceutical conferences to stay updated with emerging trends and advancements in the healthcare and pharmaceutical industry.