Ozempic was a game changer. Now scientists have another candidate

The drug, Orzeyful (oveporexton), developed by Japan-based pharmaceutical company Takeda, received regulatory approval in August for a type of narcolepsy. It belongs to a class of medicines called orexin agonists, which mimic the effects of orexins, brain chemicals that help maintain wakefulness.

Scientists believe these drugs could have a broader impact on medicine, potentially following a path similar to GLP-1 drugs such as Ozempic. Initially developed to treat diabetes, GLP-1 medicines later gained wider use for weight management and other conditions.

Orexins influence several brain functions, including sleep, appetite, mood, memory and attention. Researchers are now investigating whether drugs that activate orexin receptors could help treat conditions beyond narcolepsy.

How orexin drugs work

Scientists discovered orexins independently in the 1990s. Early research linked these brain chemicals to appetite, but experiments revealed a more important role in regulating wakefulness.

Researchers found that blocking orexin signals in animals could trigger sudden muscle weakness resembling cataplexy, a hallmark of narcolepsy type 1. Further studies showed that people with this form of narcolepsy often lose most of the brain cells that produce orexins.

These findings helped scientists understand why the condition develops and suggested a way to address its underlying cause.

Unlike existing treatments that mainly manage symptoms, orexin agonists activate the receptors through which orexins work. Researchers hope this approach will help restore more stable wakefulness.

Takeda began investigating the drugs in the late 2000s. An early candidate, TAK-925, showed promising results in animal studies and later human trials. The research eventually contributed to the development of Orzeyful.

People who took the drug during clinical trials reported a striking improvement in alertness, according to Emmanuel Mignot, a Stanford University sleep medicine specialist who led Takeda's late-stage trials.

Beyond narcolepsy

The commercial potential extends beyond the relatively small population of people with narcolepsy. The condition affects an estimated three million people worldwide, although many cases may remain undiagnosed.

Researchers at Alkermes are investigating whether orexin agonists can improve attention and alertness by acting on the brain systems that regulate wakefulness.

In September, the company released preliminary results from an early-stage study involving 50 adults with moderate to severe ADHD symptoms. Participants receiving the highest dose experienced a reduction in symptoms to mild levels after two weeks. The company reported that the drug was generally well tolerated, with no serious treatment-related adverse events.

Takeda has not started a dedicated ADHD trial, but further analysis of its narcolepsy research found improvements in participants' memory and executive function.

Scientists are also exploring whether orexin agonists could reduce fatigue associated with conditions such as multiple sclerosis and Parkinson's disease.

Earlier, Qazinform News Agency reported that England urged to rethink mental health, ADHD and autism support.