Roche heads into Pharma Day with three obesity mechanisms in hand

Roche is heading into a September 28 investor event, known as Pharma Day, with four obesity programs in the spotlight — and none of them yet approved anywhere. Investment bank William Blair expects the Swiss company to release new Phase 2 results for enicepatide in people who have both obesity and type 2 diabetes, along with updates on three other candidates ^[1].

That second enicepatide study, listed on ClinicalTrials.gov as NCT06628362, carries a completion date of September 24, four days before the event ^[1].

What Roche already showed

Enicepatide, also identified in company materials as CT-388, is a once-weekly injection that activates both the GLP-1 and GIP receptors — the same two targets as tirzepatide (Mounjaro and Zepbound). Roche picked it up as a Phase 2-ready asset in its January 2024 purchase of Carmot Therapeutics ^[2].

In the Phase 2 trial called CT388-103, the 24 mg weekly dose produced a statistically significant placebo-adjusted weight loss of 22.5% at 48 weeks, with no weight-loss plateau reached by that point ^[2]. At week 48 in the 24 mg group, 95.7% of participants lost at least 5% of body weight, 87% lost at least 10%, 47.8% lost at least 20% and 26.1% lost at least 30% ^[2]. Fifty-four percent dropped below a BMI of 30, compared with 13% on placebo, and 73% of those who were prediabetic at the start returned to normal blood glucose versus 7.5% on placebo ^[2].

Most gastrointestinal side effects were mild to moderate, the company said, and 5.9% of people on enicepatide stopped treatment because of adverse events versus 1.3% on placebo ^[2]. Roche said full results would be presented at a medical congress, and that Phase 3 trials named Enith1 and Enith2 were expected to begin in the first quarter of 2026 ^[2].

Three other shots on goal

William Blair expects Pharma Day to also cover a once-daily oral candidate, the antibody emugrobart tested in combination with Zepbound (tirzepatide), and petrelintide, a once-weekly injectable amylin drug Roche is developing with Zealand Pharma ^[1]. The BioSpace write-up refers to the oral drug as both "CT-966" and CT-996 in different places, so the exact designation is unclear from the sources. Roche plans to start later-stage trials of CT-996 and petrelintide in obesity in 2026 ^[1]. The company dropped another candidate, acmopatide, earlier this year, while executives have called enicepatide a potential best-in-class asset ^[1]. Roche Pharma CEO Teresa Graham said in January the company aims to be a "top three player" in obesity ^[1].

Reports that an August licensing deal with Hanmi added a third non-incretin mechanism are not covered in the sources reviewed here, so those terms are not yet confirmed.

Why it matters for patients

None of these Roche drugs is available by prescription. Even if the Phase 3 program stays on track, a drug that started late-stage testing in 2026 would take years to reach US pharmacies, and the sources give no filing or approval dates.

The numbers also need context. A 22.5% figure is placebo-adjusted, meaning the placebo group's weight change was subtracted out — it is not the same as total weight lost, and it cannot be compared directly with results from separate trials of semaglutide or tirzepatide, which enrolled different people under different rules ^[2]. The new readout involves people with type 2 diabetes, a group that typically loses less weight on incretin drugs than people without diabetes.

The broader point is competition. Obesity drugs generated $66 billion in sales last year and could reach $105 billion to $200 billion by 2027 and beyond, according to IQVIA figures cited by William Blair ^[1]. More approved mechanisms — incretins, amylins, muscle-sparing antibodies — could eventually mean more choices and more pricing pressure.

What happens next

The companion enicepatide study lists September 24 as its completion date ^[1]. Roche's Pharma Day is September 28 ^[1]. Separately, AstraZeneca is expected to present amylin data for AZD6234 at the European Association for the Study of Diabetes meeting, running September 28 to October 2 in Italy ^[1].