09:59 AM EDT, 09/20/2024 (MT Newswires) -- Novo Nordisk ( NVO ) said Friday that a phase 2a trial of monlunabant in obesity showed that all doses achieved a "statistically significant" weight loss, but reports of mild to moderate neuropsychiatric side effects were "more frequent and dose-dependent" with the investigational drug compared with placebo.

Martin Holst Lange, head of development, said that "further work is needed to determine the optimal dosing to balance safety and efficacy" of the drug.

The phase 2a trial results showed that participants treated with a once-daily 10mg dose of monlunabant lost 7.1 kilograms after 16 weeks compared with a 0.7 kg loss with placebo, the company said.

No serious adverse events were observed, but some participants reported mild to moderate gastrointestinal problems and neuropsychiatric side effects such as anxiety, irritability and sleep disturbances, Novo Nordisk ( NVO ) said.

The company said it will launch a bigger phase 2b study in 2025 to further assess dosing and the safety profile of monlunabant over a longer period.

Novo Nordisk ( NVO ) shares were falling more than 4% in recent trading.

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