A chemically synthesised version of semaglutide, developed by the Chinese drugmaker CSPC under the code HD1916, produced weight loss equivalent to Wegovy in a 44-week randomised trial of 462 Chinese adults with obesity, published on 7 October in Diabetes, Obesity and Metabolism. For readers in the US nothing changes yet: HD1916 is not approved here, and it is not the compounded semaglutide sold through American telehealth services. What the trial shows is that a second manufacturer, using a different production route, matched the original drug in a direct comparison.
What the trial measured
The trial ran at 30 centres in China. It enrolled adults aged 18 to 75 with a body-mass index of 28 or more, the threshold China uses for obesity, and without diabetes. Participants were randomised one-to-one to a once-weekly injection of HD1916 or of Wegovy for 44 weeks. It was open-label, so participants and investigators knew which product each person received.
The primary endpoint was the percentage change in body weight. The researchers declared in advance that the two products would count as equivalent if the 95% confidence interval for the difference between them sat entirely within 4.16 percentage points either way. Weight fell by 13.1% on HD1916 and 14.4% on Wegovy, a difference of 1.35 points, with a 95% confidence interval of −0.02 to 2.72. That interval lies inside the 4.16-point margin, so by the trial’s own definition the products were equivalent.
For a hypothetical 95 kg adult, those averages translate to about 12.4 kg on HD1916 and 13.7 kg on Wegovy. The secondary results pointed the same way: 87.8% versus 90.5% of participants lost at least 5% of their weight, and 68.7% versus 73.6% lost at least 10%. Waist reductions were described as comparable. Side effects of any grade were reported in 86.5% of the HD1916 group and 89.2% of the Wegovy group, most of them grade 1 or 2.
Why a different production route matters
Wegovy’s FDA label states that the peptide backbone of its semaglutide is produced by yeast fermentation, with the molecule then modified to make it long-acting. HD1916 is described as chemically synthesised. A different route can leave different impurities, which is why a head-to-head trial with a pre-set equivalence margin is the standard way to show that a copy behaves like the original in patients rather than only on paper.
That is the gap between this trial and the compounded semaglutide sold in the US. Compounded products are not required to show equivalence in a clinical trial at all, and the FDA has repeatedly warned about how they are sourced. HD1916 went through the testing that compounded versions skip. That still does not make it a US option: the paper does not mention any US filing, price or launch date.
The result also sits where the existing evidence would predict. The 14.4% loss on Wegovy at 44 weeks is in the range seen in earlier trials of the 2.4 mg dose, although those ran longer and in different populations. The site’s semaglutide overview covers those trials.
What is not yet known
The trial was funded and partly run by the developer: five of the 15 authors work for CSPC Baike. It was open-label, which matters less for a weight measurement than for reported side effects, but still matters. It enrolled only Chinese adults, with a lower BMI entry point than US trials use, and lasted 44 weeks rather than the 68 of Wegovy’s main trials. The point estimate also favoured Wegovy, and the upper end of the interval allows a gap of up to 2.7 points: “equivalent” here means within the agreed margin, not identical. We read the published abstract; the full paper was not accessible to us, so doses and dropout rates are not reported here. The ClinicalTrials.gov record NCT06604624, sponsored by CSPC Baike with 462 participants enrolled, matches the trial’s size and sponsor.
Sources: Gao L, Ma Y, Zhang Q, et al. “Efficacy and Safety of Chemically Synthesized Semaglutide Injection (HD1916) for the Treatment of Obesity: A Multicenter, Randomized, Phase III Trial”, Diabetes, Obesity and Metabolism, published online 7 October 2026, doi:10.1111/dom.71354. ClinicalTrials.gov NCT06604624, “Semaglutide in Treatment of Obesity”. Wegovy prescribing information, FDA label, description section.
