Clinical Scorecard: FDA approves olanzapine injection for schizophrenia

At a Glance

Key Highlights

• The FDA approved once-monthly subcutaneous olanzapine (Weltruza) for adults with schizophrenia.
• The formulation does not require loading doses, oral supplementation, or routine post-injection monitoring.
• In the 8-week SOLARIS placebo-controlled period, all three monthly doses met the primary endpoint of change in PANSS total score.
• Weight gain was reported in 35% of olanzapine-treated patients and 8% of placebo recipients during the placebo-controlled period.
• No suspected or confirmed PDSS cases were reported through 3,470 injections by week 56; prescribing information states that whether PDSS can occur remains unknown.

Guideline-Based Recommendations

Diagnosis

Management

• The approved indication is treatment of adults with schizophrenia.
• Monthly strengths of 318 mg, 425 mg, and 531 mg correspond to oral olanzapine doses of 10 mg, 15 mg, and 20 mg daily, respectively.
• The formulation does not require loading doses or oral supplementation.

Monitoring & Follow-up

• Assess metabolic risk before treatment and monitor blood glucose and other metabolic parameters during therapy.
• Routine post-injection monitoring is not required for this formulation, according to the article.

Risks

• Weight gain and metabolic abnormalities were consistent with the known safety profile of oral olanzapine.
• Other commonly reported adverse events included somnolence, headache, constipation, and injection-site reactions.
• Clinically important risks include hyperglycemia, dyslipidemia, weight gain, neuroleptic malignant syndrome, tardive dyskinesia, orthostatic hypotension, and drug reaction with eosinophilia and systemic symptoms.
• Olanzapine carries a boxed warning for increased mortality in older adults with dementia-related psychosis and is not approved for this population.
• No PDSS cases were reported in the cited trial data, but whether PDSS can occur with olanzapine remains unknown.

Patient & Prescribing Data

Adults with schizophrenia; SOLARIS enrolled 675 patients aged 18 to 64 years.

In the initial 8-week trial period, patients received monthly olanzapine 318 mg, 425 mg, or 531 mg, or placebo. All three doses met the primary PANSS endpoint. Adverse event-related discontinuations occurred in 1% to 3% of patients in both groups.

Clinical Best Practices

• Assess metabolic risk before starting treatment.
• Monitor blood glucose and other metabolic parameters during therapy.
• Do not use for older adults with dementia-related psychosis; the drug is not approved for this population.

Related Resources & Content

• Teva Pharmaceutical Industries Ltd. FDA approval announcement for Weltruza, October 9, 2026.
• Teva Pharmaceutical Industries Ltd. SOLARIS phase 3 efficacy, safety, and tolerability data, 2024.
• Teva Pharmaceutical Industries Ltd. SOLARIS long-term safety data, 2025.
• ClinicalTrials.gov. Study of olanzapine extended-release injectable suspension in patients with schizophrenia (SOLARIS), NCT05693935.