FDA Provides Feedback to Saniona on Development of Tesomet for PWS

The U.S. Food and Drug Administration (FDA) has provided some recommendations to Saniona regarding the development of Tesomet to treat Prader-Willi syndrome (PWS).

In particular, the agency is advising the company to conduct a Phase 3 trial to follow the planned Phase 2b clinical trial, as well as including children younger than 12.

The written feedback from the FDA follows a pre-investigational new drug submission, in which Saniona inquired if data from the Phase 2b study would be sufficient to support the potential approval of Tesomet in PWS.

Because Tesomet is a new type of molecule, the FDA’s Division of Psychiatry within the Office of Neuroscience said a Phase 3 study is necessary to confirm the safety and efficacy of the investigational therapy.

“We now have a clear path forward for the development of Tesomet as a novel treatment for PWS, and we look forward to further engaging with the FDA to clarify the best path for bringing Tesomet to patients,” Rami Levin, President and CEO of Saniona, said in a press release.

The two main active ingredients in Tesomet are tesofensine and metoprolol. Tesofensine is considered a triple monoamine reuptake inhibitor, which means it prevents the reabsorption of three neurotransmitters — dopamine, serotonin, and noradrenaline — by nerve cells.

Tesofensine was originally developed as a treatment for neurodegenerative diseases, but initial clinical studies found it was ineffective. However, what researchers did see is that the medication caused unintended weight loss in patients, and studies pivoted toward potentially developing it to treat excessive weight.

Because tesofensine can cause an abnormal heart rate, developers paired it with metoprolol, a beta-blocker designed to lower blood pressure and improve circulation.

Saniona completed a Phase 2a trial (NCT03149445) investigating the safety and efficacy of Tesomet in young adults with PWS. The study found that patients receiving once-daily Tesomet showed a decrease in weight, body mass index (BMI), and hyperphagia, or excessive eating, compared with patients on a placebo.

In particular, Tesomet, at 0.25 mg per day, caused a 69% decrease in hyperphagia over the three-month period, determined by a questionnaire that asked caregivers about eating habits.

Following these results, Saniona is now planning to launch the Phase 2b trial in the first half of 2021 to evaluate multiple doses of Tesomet in adults and adolescents with PWS.

The FDA also provided feedback to Saniona regarding the potential use of Tesomet as a treatment for hypothalamic obesity, recommending a Phase 2b study followed by a Phase 3 study, similar to its guidance for PWS.

The agency also cautioned that Tesomet might be used off-label in people with general obesity. Due to this risk, it has requested that Saniona either investigate how Tesomet affects the cardiovascular system, or clarify how it will restrict Tesomet to patients with hypothalamic obesity. Discussions regarding further development of Tesomet for this condition will continue, according to the company.