Ribupatide (HRS9531) is an investigational GLP-1 and GIP dual receptor agonist, the same mechanism as tirzepatide. Jiangsu Hengrui Pharmaceuticals developed it in China, and Kailera Therapeutics holds the rights elsewhere. It is being developed as a weekly injection and a daily tablet. In a 48-week Chinese phase 3 trial, the 6 mg weekly injection produced 17.7% average weight loss vs 1.4% on placebo.
The single most important fact: ribupatide is not approved anywhere as of November 7, 2026. Chinese regulators are reviewing two applications, for weight management (accepted September 2025) and for type 2 diabetes (accepted September 2026). The global phase 3 program, KaiNETIC, finished enrollment of about 5,000 people; Kailera expects results in mid-2028 (Kailera Q3 2026 release, SEC). No body-composition data have been published.
This page summarizes what the published studies, trial registrations and company disclosures report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | Dual GLP-1 and GIP receptor agonist (peptide) |
| Codes | HRS9531 (Hengrui); KAI-9531 (injection) and KAI-9531-T (tablet) (Kailera) |
| Developers | Jiangsu Hengrui Pharmaceuticals (Greater China); Kailera Therapeutics (rest of world) |
| Route | Subcutaneous injection once weekly; oral tablet once daily |
| Doses studied | Injection 2–8 mg in China, up to 10 mg in global phase 3, 10–20 mg in a US phase 2b; tablet 10–50 mg daily |
| Half-life | 7–8 days with weekly dosing (phase 1) |
| Status (November 7, 2026) | Investigational; NDAs under review in China; global phase 3 fully enrolled |
| WADA status | Not named on the 2026 List; unapproved, so it falls under S0 (non-approved substances) |
What it is
Ribupatide is a synthetic peptide that activates two gut-hormone receptors:
- the GLP-1 receptor, which reduces appetite, slows stomach emptying and raises insulin when blood sugar is high;
- the GIP receptor, the second incretin receptor, which also contributes to insulin release and is thought to add to weight loss when combined with GLP-1 activity.
That is the same pair targeted by tirzepatide, VK2735 and enicepatide, but ribupatide is a different molecule. In Kailera’s IPO prospectus, the company said lab tests showed about three times tirzepatide’s binding affinity at the GLP-1 receptor and about half its affinity at the GIP receptor, and a half-life roughly two days longer (Kailera prospectus, SEC). These are developer statements, not head-to-head clinical findings.
Hengrui licensed rights outside Greater China to Kailera, a US company that listed on Nasdaq in 2026. The same molecule is used in both the injection and the tablet, but the two are separate programs with separate data.
How it compares with related drugs
| Drug | Receptors | Status (November 2026) | Library page |
|---|---|---|---|
| Tirzepatide | GIP and GLP-1 | Approved | Tirzepatide |
| Ribupatide | GIP and GLP-1 | Under review in China; phase 3 elsewhere | This page |
| Enicepatide | GIP and GLP-1 (signal-biased) | Phase 3 | Enicepatide |
| VK2735 | GIP and GLP-1 | Phase 3 | VK2735 |
| Semaglutide | GLP-1 | Approved | Semaglutide |
| Retatrutide | GIP, GLP-1 and glucagon | Investigational | Retatrutide |
Pharmacokinetics
The first-in-human study, published in 2026, gave single doses (0.1–8.1 mg) and four weekly doses (0.9–5.4 mg) to 90 healthy Chinese volunteers (He et al., Diabetes Obes Metab 2026):
- Half-life after multiple doses was 7–8 days, which suits weekly injection.
- Weight fell by 4.3–7.7 kg (6.7–9.6%) after four weekly doses, vs 1.2 kg (1.4%) on placebo.
- Safety: all adverse events were mild to moderate, with no serious events.
- Preclinical work showed good absorption under the skin in rats and monkeys and lower food intake and weight in obese mice.
A separate single-dose bridging study in Australia (49 adults) found similar weight-adjusted drug exposure in Asian and non-Asian participants. This supports using Chinese efficacy data in global trials (Hengrui ADA 2026 release).
Regulatory status
Status checked on November 7, 2026:
- China, weight management. The NMPA (China’s drug regulator) accepted an application for ribupatide injection for long-term weight management in adults in September 2025. It was still under review in September 2026 (Hengrui, September 2026).
- China, type 2 diabetes. A second application, for glycemic control in adults with type 2 diabetes, was accepted around September 2026, based on two phase 3 trials (PRIME-1 and PRIME-2) (Hengrui, September 2026).
- Global injection program. KaiNETIC is three placebo-controlled phase 3 trials, KaiNETIC-1 (NCT07284875), KaiNETIC-2 (NCT07284901, with type 2 diabetes) and KaiNETIC-3 (NCT07284979, which also includes an open-label semaglutide 2.4 mg arm). Together they enroll about 5,000 adults and test weekly doses up to 10 mg over 76 weeks. All are fully enrolled, with data expected in mid-2028 (Kailera Q3 2026 release).
- High-dose study. A US phase 2b trial (NCT07458269) tests 10, 13, 16 and 20 mg weekly over 48 weeks in about 260 people with a BMI of 35 or more. Data are expected in mid-2027.
- Tablet. After an end-of-phase-2 meeting with the FDA, Kailera plans to start a global phase 3 program of daily oral ribupatide, at doses up to 25 mg over 60 weeks, in the first half of 2027. In China, a tablet phase 3 trial (NCT07670884) is recruiting.
- Other Chinese trials registered on ClinicalTrials.gov include sleep apnea, heart failure with preserved ejection fraction, knee osteoarthritis and a cardiovascular outcomes trial in about 9,262 people (NCT07551492).
What the research shows
Injection: China phase 2 in obesity
On 8 mg weekly, average weight loss at 36 weeks was 23.6%, compared with 1.8% on placebo, under the efficacy estimand (which assumes people stay on treatment). Under the treatment-policy estimand (which counts everyone randomized), the figures were 22.8% vs 1.7% (Kailera prospectus). This is the most-quoted figure for the drug. It comes from a mid-sized phase 2 trial, and the full results had not been published in a peer-reviewed journal by November 2026.
Injection: China phase 3 in obesity (HRS9531-301)
This 48-week, double-blind trial enrolled 567 Chinese adults with obesity or overweight plus at least one weight-related condition, without type 2 diabetes. Average age was 34.4 years, average weight 93.0 kg and average BMI 33.3. Doses were raised over up to 20 weeks (Kailera prospectus):
| Outcome at 48 weeks | Placebo | 2 mg | 4 mg | 6 mg |
|---|---|---|---|---|
| Weight change, treatment-policy estimand | −1.4% | −10.7% | −16.4% | −17.7% |
| Weight change, efficacy estimand | −1.4% | −11.2% | −17.4% | −19.2% |
| Lost ≥5% (treatment policy) | 16% | 68.1% | 88% | 85.7% |
At 6 mg, 75.4% lost at least 10%, 63.8% at least 15% and 44.4% at least 20%. On placebo, the figures were 9.2%, 7.1% and 3.5%. Weight was still falling at week 48 in the 4 mg and 6 mg groups. Blood pressure, lipids, HbA1c and an inflammation marker (hs-CRP) also improved.
The fall from about 23% in phase 2 to about 18% in phase 3 is not a red flag. Bigger trials enroll a broader mix of people and use stricter analyses, and here the doses and trial lengths were also different.
Injection: type 2 diabetes (PRIME-1 and PRIME-2)
Hengrui reported two 36-week phase 3 trials in Chinese adults (Hengrui, August 2026; Hengrui, September 2026):
| Trial | Design | HbA1c reduction at 36 weeks |
|---|---|---|
| PRIME-1 (HRS9531-302) | 218 patients on diet and exercise only; vs placebo | −2.67 points on 4 mg |
| PRIME-2 (HRS9531-303) | 884 patients on metformin with or without an SGLT2 inhibitor; vs semaglutide 1 mg | −2.78 points (4 mg) and −2.34 (2 mg) vs −2.29 (semaglutide) |
Both doses met the non-inferiority goal against semaglutide, and 4 mg was statistically better (difference −0.49 points). HbA1c of 6.5% or lower was reached by 85.0% on 4 mg, 69.0% on 2 mg and 64.3% on semaglutide. Note that 1 mg is semaglutide’s diabetes dose, not the 2.4 mg obesity dose.
Tablet: China phase 2
A 26-week trial randomized 166 adults with obesity and no diabetes to daily oral ribupatide or placebo (Hengrui ADA 2026 release):
| Daily dose | Weight change (efficacy / treatment policy) | Lost ≥15% |
|---|---|---|
| Placebo | −2.3% / −2.1% | — |
| 10 mg | −6.9% / −6.7% | 4.8% |
| 25 mg | −12.1% / −11.9% | 38.6% |
| 50 mg | −12.1% / −11.4% | 37.5% |
The 50 mg dose added nothing over 25 mg, which is the dose Kailera has chosen as its top oral phase 3 dose.
Body composition: no data yet
For people interested in keeping muscle, the key gap is that no DXA or MRI body-composition results have been published for ribupatide. The global KaiNETIC trials do not list lean mass as a key secondary endpoint in Kailera’s description (Kailera prospectus). A small investigator-led Chinese trial on weight regain lists “body fat rate” as an outcome, but its registry status is unknown and no results are posted (NCT06287437).
Until data appear, the closest guide is the incretin class. In a meta-analysis of trials with at least 10% weight loss, fat-free mass made up 33.3% of the weight lost with incretin drugs, vs 7.7% with diet plus exercise (Busk-Cirera et al., Diabetes Obes Metab 2026). That gap is why resistance training and adequate protein are usually advised alongside these drugs.
Use alongside testosterone or anabolic steroids
No trial has combined ribupatide with TRT or anabolic steroids. The only human data on combining a GLP-1/GIP drug with testosterone come from a pilot study of 10 obese hypogonadal men on tirzepatide. The five men who also received testosterone undecanoate regained lean mass over six months, while the five on tirzepatide alone lost it (Seminara et al., Minerva Endocrinol 2026). That study is far too small to guide practice, and it involved replacement doses in men with low testosterone, not supraphysiologic AAS use.
Side effects and risks
Gastrointestinal effects
As with tirzepatide, the main side effects are nausea, vomiting, diarrhea and reduced appetite, mostly during dose increases. Kailera reports that in Hengrui’s trials most adverse events were mild or moderate and leveled off once participants reached doses of 3 mg and above (Kailera prospectus). That observation is part of why the global trials go up to 10 mg.
Detailed per-dose adverse-event rates for the injection trials have not been published in a peer-reviewed journal. For the tablet, the 10/25/50 mg groups reported (Hengrui ADA 2026 release):
| Event | 10 mg | 25 mg | 50 mg |
|---|---|---|---|
| Nausea | 11.9% | 22.7% | 20.0% |
| Diarrhea | 4.8% | 20.5% | 5% |
| Vomiting | 2.4% | 11.4% | 7.5% |
No one in the oral groups permanently stopped treatment or had the dose reduced because of gastrointestinal events.
Gaps in the safety data
- Limited peer review. Most efficacy and safety data are company-reported.
- Mostly Chinese populations. The completed trials were run in China. The bridging study supports similar exposure across ethnic groups, but larger global safety data will come from KaiNETIC.
- Class warnings. Approved GLP-1-based drugs such as semaglutide carry warnings for thyroid C-cell tumors in rodents, pancreatitis and gallbladder disease (Wegovy label, DailyMed). Whether these apply to ribupatide is not established.
Unregulated products
Outside China’s pending review, ribupatide is available only in clinical trials. Products sold online as “HRS9531” or “ribupatide” are not the trial drug, and their contents cannot be assumed.
Legal status and use in sport
Ribupatide is not named on the WADA Prohibited List, and incretin drugs as a class are not prohibited. Because no government regulator has approved it, it falls under S0, which bans “any pharmacological substance” with no current approval for human therapeutic use, including “drugs under pre-clinical or clinical development” (WADA 2026 Prohibited List). It is therefore prohibited at all times.
If China approves it, the S0 status would no longer apply, because S0 covers only substances with no approval by any government health authority. It would then be treated like tirzepatide: not prohibited. Tirzepatide markers, however, are on WADA’s 2026 Monitoring Program (WADA 2026 Monitoring Program).
Key takeaways
- A tirzepatide-class drug from China. Ribupatide activates GLP-1 and GIP receptors, has a half-life of 7–8 days and is developed as a weekly injection and a daily tablet.
- Not approved yet. China is reviewing weight-management and diabetes applications; the global KaiNETIC phase 3 program (about 5,000 people) reports in mid-2028.
- Strong phase 3 weight loss in China. 17.7% at 48 weeks on 6 mg (treatment policy) vs 1.4% on placebo; up to 23.6% at 36 weeks in phase 2.
- Beat semaglutide 1 mg on HbA1c. In type 2 diabetes, 4 mg lowered HbA1c by 2.78 points vs 2.29 for semaglutide 1 mg.
- Tablet plateaus at 25 mg. Oral ribupatide gave about 12% weight loss at 26 weeks, with no gain from 50 mg.
- No lean-mass data and banned in sport for now. No body-composition results exist, and as an unapproved drug it falls under WADA S0.
Sources
- Kailera Therapeutics. Kailera reports third quarter 2026 financial results and provides business updates. Press release (Form 8-K, Exhibit 99.1), November 4, 2026. SEC.
- Kailera Therapeutics. Prospectus (Form 424B4), April 2026. SEC.
- He K, Wei Y, Zhao H, et al. Preclinical and First-In-Human Evaluation of Ribupatide (HRS9531), a Dual GLP-1/GIP Receptor Agonist. Diabetes Obes Metab. 2026;28(12):11643–11652. PubMed.
- Jiangsu Hengrui Pharmaceuticals. Hengrui Pharma and Kailera Therapeutics present ribupatide clinical data at ADA 2026. June 5, 2026. Hengrui.
- Jiangsu Hengrui Pharmaceuticals. Ribupatide development update and PRIME-2 results. August 4, 2026. Hengrui.
- Jiangsu Hengrui Pharmaceuticals. NMPA accepts new drug application for ribupatide injection for type 2 diabetes. September 10, 2026. Hengrui.
- ClinicalTrials.gov. KaiNETIC-1: efficacy and safety of ribupatide in participants living with obesity or overweight with weight-related comorbidities. NCT07284875. ClinicalTrials.gov.
- ClinicalTrials.gov. KaiNETIC-2: efficacy and safety of ribupatide administered once weekly in participants living with obesity or overweight and type 2 diabetes. NCT07284901. ClinicalTrials.gov.
- ClinicalTrials.gov. KaiNETIC-3: efficacy and safety of ribupatide administered once weekly compared with semaglutide and placebo. NCT07284979. ClinicalTrials.gov.
- ClinicalTrials.gov. Efficacy and safety of ribupatide (KAI-9531) administered once weekly in participants living with obesity (phase 2b, high dose). NCT07458269. ClinicalTrials.gov.
- ClinicalTrials.gov. Other ribupatide trials: HRS9531 tablets phase 3, NCT07670884; cardiovascular outcomes trial, NCT07551492; weight regain trial, NCT06287437. ClinicalTrials.gov.
- Busk-Cirera L, Carlsen IØ, Madsen LB, et al. Effects of Incretin-Based Therapies, Diet and Exercise Interventions, and Bariatric Surgery on Fat-Free Mass in Adults With Overweight or Obesity: A Systematic Review and Meta-Analysis. Diabetes Obes Metab. 2026;28(9):7737–7751. PubMed.
- Seminara G, Leuzzi M, Meduri L, et al. Effects of testosterone undecanoate as add-on therapy in obese hypogonadal men that are late responders to tirzepatide: a pilot study. Minerva Endocrinol (Torino). 2026;51(2):104–117. PubMed.
- Novo Nordisk. Wegovy (semaglutide) injection prescribing information. Revised June 2026. DailyMed.
- World Anti-Doping Agency. The 2026 Prohibited List. WADA 2026 Prohibited List.
- World Anti-Doping Agency. The 2026 Monitoring Program. WADA.