Decades-Old Schizophrenia Medication Approved in New Monthly Injectable Formulation
Adults living with schizophrenia now have access to a newly approved once-monthly subcutaneous injectable version of olanzapine, marketed as Weltruza, following an announcement by Teva Pharmaceuticals. While oral olanzapine has served as a widely prescribed atypical antipsychotic for over thirty years, daily dosing can present adherence hurdles that complicate symptom management and long-term stability.
A Streamlined Option Without Specialized Monitoring
Unlike previous long-acting injectable formulations of the medication—such as Zyprexa Relprevv, which requires a strict Risk Evaluation and Mitigation Strategy program and a mandatory three-hour monitoring window—the newly approved product eliminates the need for intensive observation. Previous formulations carried risks associated with post-injection delirium/sedation syndrome (PDSS), a condition marked by symptoms like confusion, agitation, and extreme drowsiness. Clinical trials for the new subcutaneous formulation reported no cases of PDSS, and the treatment requires neither loading doses nor booster injections to achieve therapeutic blood levels.
Dr. Christoph Correll of the Zucker School of Medicine at Hofstra/Northwell noted that while the medication has long been a foundational treatment choice, daily oral adherence remains a significant hurdle. He stated that providing a subcutaneous long-acting option that achieves therapeutic levels without oral cotreatment or specialized loading doses can help empower patients and assist clinicians in managing a complex condition.
Clinical Trial Findings and Dosing Specifics
The approval of the new formulation was backed by data from the phase III SOLARIS trial. According to findings highlighted by Teva Pharmaceuticals, all evaluated dose groups outperformed placebos regarding the mean difference in score changes on the Positive and Negative Syndrome Scale from baseline to week eight. Additional secondary endpoints, including the Clinical Global Impressions-schizophrenia scale and the Personal and Social Performance Scale, similarly demonstrated superiority compared to placebo.
To match standard oral dosages of 10 mg, 15 mg, and 20 mg, the subcutaneous injection will be accessible in 318 mg, 425 mg, and 531 mg strengths. The overall safety profile observed during the SOLARIS study aligned closely with oral olanzapine. Commonly reported adverse events included increased weight, somnolence, headaches, and constipation, alongside localized injection-site reactions such as pain, swelling, erythema, induration, and pruritus.
Important Safety Information and Warnings
Despite clinical trials showing an absence of PDSS events, the product labeling maintains PDSS among its warnings and precautions. Additionally, the medication carries a boxed warning indicating an elevated risk of mortality among elderly patients suffering from dementia-related psychosis. Other noted risks detailed in the warning sections include neuroleptic malignant syndrome, metabolic shifts, tardive dyskinesia, orthostatic hypotension, seizures, potential cognitive and motor impairment, laboratory abnormalities, anticholinergic effects, and blood disorders such as leukopenia, neutropenia, and agranulocytosis.
Source: MedPage Today
