Efficacy and safety of TV-46000, a long-acting, subcutaneous, injectable formulation of risperidone, for schizophrenia: a randomised clinical trial in the USA and Bulgaria.

Background: TV-46000 is a long-acting, subcutaneous, antipsychotic agent that combines risperidone and an innovative, copolymer-based drug delivery technology in a suspension that was approved in April, 2023 for subcutaneous use. The aim of the phase 3 Risperidone Subcutaneous Extended-release (RISE) study was to evaluate the efficacy of TV‑46000 in schizophrenia.

Methods: The RISE study consisted of two treatment stages: a 12-week, open-label stabilisation phase with oral risperidone (stage 1), and an open-ended, randomised, double-blind, placebo-controlled, relapse-prevention phase with subcutaneous TV-46000 (stage 2) done at 69 clinical sites across the USA and Bulgaria. Patients diagnosed with schizophrenia more than 1 year before screening by DSM-5 criteria and confirmed at screening by the Structured Clinical Interview for DSM-5 and who had at least one relapse within 24 months before screening were eligible for enrolment. Patients who were outpatients and stabilised in stage 1 continued to stage 2 and were randomly assigned 1:1:1 by a computer-generated randomisation list to receive either subcutaneous TV-46000 once monthly, TV-46000 once every 2 months, or placebo until relapse, early discontinuation, or the study was stopped because the prespecified stopping criterion of at least 90 relapse events was met. The primary endpoint was time to impending relapse of the intention-to-treat patient population in stage 2. This study is registered with ClinicalTrials.gov, number NCT03503318, and is complete.

Findings: The study enrolled the first patient on June 1, 2018, and the last patient completed on Dec 3, 2020. 1267 patients were screened, 863 enrolled, and 544 (male, n=332 [61%], female, n=212 [39%]; mean [SD] age, 49·3 [10·98] years; Black or African American, n=322 [59%]; White, n=206 [38%]; Asian, n=7 [1%]; Native Hawaiian or other Pacific Islander, n=2 [<1%]; race not reported, n=3 [<1%]; other race, n=4 [<1%]; Hispanic or Latinx, n=117 [22%]) randomly assigned to subcutaneous TV-46000 once monthly (n=183), TV-46000 once every 2 months (n=180), or placebo (n=181). Time to impending relapse was significantly prolonged by 5·0 times with TV-46000 once monthly (hazard ratio, 0·200 [95% CI 0·109-0·367]; p<0·0001) and by 2·7 times with TV-46000 once every 2 months (0·375 [0·227-0·618]; p<0·0001) versus placebo. Most frequently reported treatment-related adverse events (ie, ≥5% of patients in either TV-46000 group) that occurred more often in patients receiving TV-46000 (once monthly or once every 2 months) versus placebo were injection site nodules (7% for TV-46000 once monthly, 7% for TV-46000 once every 2 months, 3% for placebo), weight increased (4%, 6%, 2%, respectively), and extrapyramidal disorder (5%, 3%, 0% respectively). Serious adverse events were reported for eight (4%) patients in the TV-46000 once-monthly group, ten (6%) patients in the TV-46000 once-every-2-months group, and 14 (8%) patients in the placebo group. The safety profile of TV-46000 was consistent with other approved formulations of risperidone. No new safety signals were identified.

Interpretation: In patients with schizophrenia, subcutaneous TV-46000 once monthly and once every 2 months significantly delayed impending relapse versus placebo. TV-46000 is an effective long-acting, subcutaneous, antipsychotic agent treatment option in adult patients with schizophrenia, with a favourable benefit-risk profile.

Funding: Teva Branded Pharmaceutical Products R&D.