Saniona cleared for second phase of Prader-Willi syndrome trial

Saniona has gotten the go-ahead it needs to continue a midstage trial of its combination therapy for Prader-Willi syndrome (PWS), a debilitating genetic disorder that causes insatiable appetite and obesity.

Preliminary data from the phase 2a trial of a fixed-dose combination of monoamine reuptake inhibitor tesofensine and beta blocker metoprolol (Tesomet) reported last October showed that the duo was able to achieve clinically meaningful weight loss and curb the desire to overeat (hyperphagia) in nine adolescents with PWS.

It had hoped to recruit 15 patients, however, and the smaller patient population—as well as the failure of one patient on placebo and four on Tesomet to complete the study—prompted an analysis of the data before the trial could progress to the larger, second stage.

With that analysis complete, the phase 2a trial can now get underway once again with a target enrolment of 10 adolescents with PWS, says Denmark-based Saniona, which sees Tesomet as the drug most likely to become its first own-commercialized product.

A key finding from the initial patient group was that plasma concentrations of tesofensine were two to four times higher compared to previous studies of the same tesofensine dose as a monotherapy in obese patients and alongside metformin in diabetic patients. The second stage of the trial will therefore use a lower dose, but the outcome measures will stay the same—i.e. change in body weight over 12 weeks and eating behavior.

The Sweden-listed company raised almost $17 million in a fundraising towards the end of 2017 which it says will fund its clinical programs through 2020—long enough to bring the PWS trial to conclusion.

“By pursuing an orphan indication such as PWS, we may develop and commercialize our own product in the U.S. and Europe within a relative short time and at a limited investment in an indication where the commercial opportunities appear to be very large,” said Jørgen Drejer, Ph.D., Saniona’s founder and CEO.

“We believe that low dose Tesomet could prove to be a compelling treatment for adolescents with this currently untreatable disease.”

Other companies have been trying to develop therapies for PWS, including Zafgen which started a phase 3 trial of MetAP2 inhibitor beloranib in 2016 but suspended the program after two patients died from clot-related side effects. The company turned its attention to a follow-up drug with a cleaner profile, reporting phase 1 data last year. Meanwhile, French biotech Alizé Pharma has AZP-531, billed as a first-in-class analogue of unacylated ghrelin (UAG), in phase 2 testing.

Saniona has partnered tesofensine monotherapy as an obesity drug with Medix, which is running a phase 3 trial in obese Mexican patents that should read out in early 2019. It’s also developing Tesomet in phase 2 for Type 2 diabetes.