Structure reports 72‑week aleniglipron weight loss and early oral amylin results

Structure Therapeutics reported new results on September 8 for two experimental oral medicines: the GLP-1 drug aleniglipron and the amylin candidate ACCG-2671. The results come from separate studies at very different stages of development.

The company reported up to 16.2% average weight loss through 72 weeks with aleniglipron. Its first single-dose amylin study found an early weight-loss signal, alongside nausea and vomiting at higher doses. Neither medicine has FDA approval.

Aleniglipron results come from an extension without a placebo group

The ACCESS trial first compared aleniglipron with placebo, an inactive treatment, for 36 weeks. Participants who completed that period had the option to enter another 36 weeks of treatment. In this open-label extension, everyone received aleniglipron and knew the treatment.

The extension enrolled 151 participants. Groups originally assigned to 45, 90 or 120 mg reached average weight reductions of 11.6%, 14.4% and 16.2%, respectively. The company used a statistical model to estimate the average weight changes. They describe changes from the original baseline, not differences from placebo. Participants increased their doses during the extension, with the move to 180 mg after week 60.

This distinction matters. The figures do not describe 72 weeks at a fixed 180 mg dose. They also do not show how the medicine compares with another obesity drug. People who complete a trial and choose to continue can differ from those who stop early.

The safety table lists nausea, vomiting, diarrhea and constipation during the extension. Five participants stopped treatment because of adverse events, meaning health problems reported during the study. Eleven had serious adverse events, which does not by itself establish that the drug caused those events.

The company also reported better tolerability among former placebo participants who started aleniglipron at 2.5 mg. That comparison involved different groups and dose schedules. It does not isolate the effect of the lower initial dose.

The amylin result involved six people at the highest dose

ACCG-2671 acts on amylin and calcitonin receptors, the cell targets for those hormones. Its first study enrolled 31 adults without obesity. Each received one dose of the experimental drug or placebo.

The six people who received 10 mg lost an average of 3.3% of body weight by day 24. All six reported nausea and vomiting, described as mild or moderate. No serious adverse events were reported in this small study.

A single-dose result in adults without obesity cannot establish sustained benefit for people with obesity. Six people also cannot reveal the full range of uncommon harms. This is an early signal for further research, not an estimate of expected weight loss during routine treatment.

Larger trials still need to establish the benefits and risks

ClinicalTrials.gov lists the placebo-controlled ACCOMPLISH-1 and ACCOMPLISH-2 studies of aleniglipron as recruiting. Their planned enrollment totals 4,700 adults, with at least 76 weeks of treatment. The second study includes adults with type 2 diabetes.

Longer, controlled trials can help separate drug effects from changes that occur for other reasons. They also provide more information about treatment discontinuation and adverse events over time.

These results remain company-reported trial findings. They do not establish comparative superiority, an approved dose, a price or a date when patients can get either medicine. The two studies cannot be combined to predict the results of an oral GLP-1 and amylin combination.