Structure's diabetes pill misses weight-loss expectations in mid-stage trial

By Michael Erman

(Reuters) -Structure Therapeutics' diabetes pill missed market expectations for weight loss in a mid-stage trial and fell short of results from a similar treatment from rival Eli Lilly, sending the biotech company's shares tumbling more than 50% on Monday.

The pill - called GSBR-1290 by Structure - also helped obese patients reduce their weight by nearly 5% after eight weeks.

It belongs to the same class of diabetes and obesity treatments as Novo Nordisk's Wegovy and Ozempic and Lilly's Mounjaro and Zepbound, known as GLP-1 agonists.

These four treatments, which bring in billions of dollars in revenue to the drugmakers, are injections.

Before the data was published, Jefferies analyst Roger Song had said he was expecting 6%-7% weight loss relative to a placebo and 1.3% reduction in HbA1c levels in diabetes patients.

Structure Therapeutics said the Phase 2 study in 94 patients was divided into a cohort with obesity and a group with type 2 diabetes. The obese patients saw an average weight loss of 4.74% versus patients who received a placebo after eight weeks.

Their actual weight loss was 5.6% - patients on placebo had a 0.8% weight loss during the period.

Patients with diabetes showed reduction of 1.01% to 1.02% in hemoglobin A1c (HbA1c) and 3.3% to 3.5% in weight at 12 weeks, relative to those who received a placebo.

"We're clearly showing a very, very good trend downwards in terms of weight loss," Structure Chief Executive Raymond Stevens said in an interview.

"At 12 weeks, we feel like we will be very comparable in terms of efficacy" to Lilly's orfoglipron - another GLP-1 pill in development.

The drug's efficacy in diabetes patients was below expectations and fell short of orforglipron, said Leerink Partners analyst David Risinger, even though he was encouraged by its clean safety and efficacy in obesity patients.

Lilly's drug was shown to reduce HbA1c levels by about 1.25%-1.75% and weight by 5%-6% after 12 weeks when adjusted for a placebo in diabetes patients in a mid-stage study, Risinger said.

GLP-1s, originally developed for type 2 diabetes, mimic the action of the GLP-1 hormone to regulate blood sugar, slow digestion and suppress appetite.

CEO Stevens said he was pleased with the drug's safety and tolerability profile. Only one of the 60 participants discontinued the study due to adverse events from the drug and the most common side effects were nausea and vomiting.

Pfizer recently decided to stop developing a twice-daily obesity pill after most patients dropped out of its mid-stage trial with high rates of side effects.

Structure said it expects full 12-week results from the obesity cohort in the second quarter of 2024. It plans to launch a larger mid-stage study in the second half of next year and a late-stage trial in 2026.

Companies developing GLP-1 drugs have been hot targets for acquisitions and licensing deals.

Recent deals include Roche's acquisition of Carmot Therapeutics for $2.7 billion upfront and AstraZeneca's purchase of rights to an experimental pill from China's Eccogene.

"We need a strategic partner for the Phase 3 and commercialization," Stevens said. "We have been getting inbound interest - we're going to evaluate those very carefully, and choose the right partner that we believe that we can work with the best to really develop this drug."

Shares of Structure Therapeutics were trading at $29.02 in early trading.

(Reporting by Michael Erman in New York, additional reporting by Mariam Sunny in Bengaluru; Editing by Christopher Cushing and Arun Koyyur)