Structure patches up holes in share price after GLP-1 linked to 6% weight loss

Now that’s more like it. After investors frowned on Structure Therapeutics’ oral GLP-1 data in December 2023, the biotech is back with a new cut showing 6% weight loss in a phase 2a study.

Structure says the data, which include the midstage test and a capsule to tablet pharmacokinetics study, support once-daily dosing with low discontinuations and a favorable safety profile, according to a Monday press release

The California biotech’s shares climbed 16% as the markets opened Monday to $39.65 compared to $34.20 at close.

Rewinding back to the end of 2023, Structure linked the oral candidate to significant reductions in blood sugar and weight in the phase 2a trial. But investors compared the results to the two heavyweights in the obesity scene—Eli Lilly’s Zepbound and Novo Nordisk’s Wegovy—and did not like what they saw. The shares dropped by half to $29.

So while today’s news has not brought Structure back to its previous high, it’s a nice reversal.

GSBR-1290 had a statistically significant placebo-adjusted mean decrease in weight of 6.2% at 12 weeks. At this point, 67% of patients treated with the medicine had achieved greater than or equal to 6% weight loss and 33% achieved greater than or equal to 10% weight loss, compared to 0% for placebo-treated patients.

A separate PK study is exploring a tablet formulation of GSBR-1290. Here, patients had placebo-adjusted mean weight loss of up to 6.9% at 12 weeks. The tablet also showed comparable exposure to the capsule and support a once-daily dosing schedule.

Safety is key in ongoing GLP-1 studies, as Lilly and Novo have by far seized the market. The leading medicines lead to significant weight loss but also have tolerability concerns, including gastrointestinal side effects and muscle loss. Structure said that GSBR-1290 had generally favorable safety and tolerability with daily dosing of 120 mg.

The most common adverse events were gastrointestinal-related, including nausea and vomiting. These were generally well tolerated and the discontinuation rate was 5% in the phase 2a obesity study and 11% in the PK study.

There were no cases of liver injury, which has been an issue with some early oral GLP-1s, including an offering from Pfizer.

“These topline results demonstrate the substantial weight loss effect of GSBR-1290 and its potential to become a best-in-class oral small molecule GLP-1RA as well as an ideal backbone for future combination therapeutics for the treatment of obesity and related diseases,” said Raymond Stevens, Ph.D., Structure CEO.

Structure will take the lessons learned from dosing into a phase 2b trial and the safety results suggest a higher dose could be used as well, according to Stevens. That test is expected to begin in the fourth quarter with an investigational new drug application headed to the FDA in the third quarter. Structure will use the tablet formulation for that 36-week trial of 300 participants.