Danish pharmaceutical company Lundbeck and its Japanese partner Otsuka have announced successful results from a Phase 3 clinical trial evaluating the efficacy, safety and tolerability of a once-monthly drug for the treatment of schizophrenia.

The 52-week, double-blind trial of aripiprazole intramuscular hit its primary endpoint – to delay the time-to-impending relapse compared to a placebo.

Improvements in symptoms were also maintained throughout the study in patients treated with the drug, while patients who received a placebo reported significantly worsening scores, Lundbeck said in a statement.

Results demonstrated that aripiprazole IM was well tolerated, with a discontinuation rate of 7.1% compared to 13.4% in patients taking the placebo.

Executive vice president Anders Gersel Pedersen, head of research and development at Lundbeck said: "We are very encouraged by these data of aripiprazole IM depot formulation, which shows that a once-monthly injection of this compound is effective in delaying the time to relapse for patients with schizophrenia.

"As relapsed patients experience further erosion of his or her mental and overall physical health, which again can lead to decreased functioning, increased morbidity and thereby worsen the overall outcome."

The study included 710 adult patients with schizophrenia who required chronic treatment with an antipsychotic agent.