CT-388

Dosing from the Literature

Published for fat loss: single doses of 0.5 to 7.5 mg, and four weekly doses stepped up from 5 mg to 7.5 or 12 mg, in adults with overweight or obesity (Chakravarthy et al., 2026). Not published: a full paper on the Phase 1’s two 22 mg cohorts (24 weeks, and 12 weeks in type 2 diabetes) or on the 48-week Phase 2 trials (up to 24 mg), which appear only in conference abstracts and Roche’s documents; no dose is approved.

No dose of CT-388 is approved. The table records the doses given in Carmot’s and Roche’s trials, as the paper, the conference abstracts, the trial records and Roche’s documents give them. All were injections under the skin (Chakravarthy et al., 2026; NCT06525935; NCT06628362). They are trial doses, not recommendations.

What It Is

CT-388 is a synthetic peptide that switches on the receptors for two gut hormones, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) (Chakravarthy et al., 2026). In 2025 WHO published enicepatide as its proposed international nonproprietary name, with the formula C226H345FN48O67, and classed it as a dual GIP and GLP-1 receptor agonist and an antidiabetic (WHO, 2025); FDA’s substance registry also lists enicepatide as its US adopted name (FDA GSRS). Roche also codes it RO7795068 and RG6640 (NCT06525935), and the developers give its molecular weight as 4,825.4 g/mol (Chakravarthy et al., 2026).

FDA’s substance registry lists its chain as 38 building blocks: X-EGTFTSDYSI-X-LDKIAQKAFVQWLIAGGPSSGAPPPS, where the first X is a β-alanine capped with a small fluorine-carrying chemical group, the second X is 2-methylalanine (Aib), the lysine at position 19 carries a 20-carbon fatty diacid on a linker, and the end is amidated (FDA GSRS; WHO, 2025). Set against tirzepatide’s record, positions 2 to 38 match tirzepatide’s positions 3 to 39, including tirzepatide’s second Aib, the same fatty-acid side chain on the same lysine and the amidated end; the difference is at the start, where tirzepatide’s first two building blocks, tyrosine and Aib, are replaced by the capped β-alanine (FDA GSRS; Zepbound label).

Carmot Therapeutics, a private company in Berkeley, California, found CT-388 by screening thousands of variants of a dual GLP-1/GIP peptide with its Chemotype Evolution platform, choosing for cAMP signaling with little β-arrestin recruitment at both receptors (Chakravarthy et al., 2026; Roche, December 4, 2023). Its first human trial began in April 2021 (NCT04838405). In December 2023 Roche agreed to buy Carmot for USD 2.7 billion upfront plus up to USD 400 million in milestone payments, naming CT-388 the lead asset (Roche, December 4, 2023). Roche has since reported a 24-week Phase 1b cohort (Roche, May 16, 2024) and two 48-week Phase 2 trials (Roche, January 27, 2026; Roche, September 22, 2026), and two Phase 3 trials, ENITH-1 and ENITH-2, began in March 2026 (NCT07351045; NCT07351058).

In March 2025 Roche and Zealand Pharma agreed to develop Zealand’s amylin analog petrelintide alone and as a fixed-dose combination with CT-388 (Roche, March 12, 2025). CT-388 is not CT-996, a once-daily oral small-molecule GLP-1 receptor agonist from the same Carmot deal, nor CT-868, a once-daily injectable GLP-1/GIP agonist meant for people with type 1 diabetes and overweight or obesity (Roche, December 4, 2023); Roche listed CT-868, now named acmopatide, as not advancing to Phase 3 in June 2026 (Roche, June 8, 2026).

PubMed returns 3 records for “CT-388” and none for “enicepatide” (October 4, 2026): the developers’ paper on CT-388 itself (Chakravarthy et al., 2026) and two reviews that mention it (Jepsen & Christensen, 2021; Neumann et al., 2026). No health authority has approved it (see Legal Status).

Mechanism of Action

The findings below come from cell tests, mice and monkeys in the developer’s paper, and from what its first human trial measured (Chakravarthy et al., 2026). The design’s proposed advantage, biased signaling, has not been tested against an unbiased drug in people (PubMed and ClinicalTrials.gov, searched October 4, 2026).

• GLP-1 and GIP receptors (cAMP signaling) — In cell lines carrying the human receptors, CT-388 fully activated the GLP-1 receptor (half-maximal concentration 0.087 nM, 99% of the maximal response) and activated the GIP receptor to 92% of its maximal response (half-maximal concentration 2.47 nM). Compared with the natural hormones it was 4-fold less potent at the GLP-1 receptor and 42-fold less potent at the GIP receptor, so its potency leans toward GLP-1, and it produced no cAMP at the glucagon or GLP-2 receptors (Chakravarthy et al., 2026). Tirzepatide leans the other way: a Lilly-led analysis found that at clinically effective doses it engages the GIP receptor more than the GLP-1 receptor (Willard et al., 2020).
• β-arrestin and receptor internalization (the “biased” design) — Unlike native GLP-1, CT-388 recruited almost no β-arrestin-2 to the human GLP-1 receptor (4% of the maximal response) and little to the GIP receptor (28%), and it barely pulled either receptor into the cell (6% at the GLP-1 receptor; below detection at the GIP receptor) (Chakravarthy et al., 2026). The developers hypothesize that receptors left on the cell surface keep signaling longer, giving longer-lasting effects on glucose and weight (Chakravarthy et al., 2026). In cells and mice, an Imperial College London group found that GLP-1 receptor agonists that recruit less β-arrestin and leave the receptor at the cell surface gave greater long-term insulin release and better blood glucose (Jones et al., 2018), and that in mice very large cuts in β-arrestin recruitment were needed for the full effect on blood glucose (Hinds et al., 2024). Tirzepatide is itself biased toward cAMP at the GLP-1 receptor but not at the GIP receptor (Willard et al., 2020).
• Insulin release that depends on glucose — In a human beta-cell line, CT-388 raised glucose-stimulated insulin secretion (half-maximal concentration 6.4 nM), and in lean monkeys a single dose raised insulin and C-peptide and lowered blood glucose during an intravenous glucose test (Chakravarthy et al., 2026). In the Phase 1’s four-week weekly-dose part, glucose during an oral glucose test fell while insulin and C-peptide generally fell too, which the authors read as better insulin sensitivity (Chakravarthy et al., 2026).
• Appetite — CT-388 cut food intake in lean and obese mice (Chakravarthy et al., 2026). Food intake was not measured in people; in the Phase 1’s four-week weekly-dose part, satiety scores rose and appetite scores fell on CT-388, and all 18 participants on weekly CT-388 reported decreased appetite as an adverse event, against none on placebo (Chakravarthy et al., 2026).
• Long action (fatty-acid side chain) — CT-388 carries a 20-carbon fatty diacid on a lysine (WHO, 2025); tirzepatide’s label says its C20 fatty diacid enables albumin binding and prolongs its half-life (Zepbound label). In the Phase 1’s adults with overweight or obesity, CT-388’s half-life averaged 123–151 hours, and blood levels peaked about 24 hours after injections of 5 mg or more (Chakravarthy et al., 2026).

What the Research Shows

Every result below comes from animal work run by or for the developer, published in the same paper as the first human trial (Chakravarthy et al., 2026). In that paper CT-388 was injected under the skin: once in the lean mice and the monkeys, every day in the 21-day and 8-week mouse studies, and once a week in the people given repeated doses (Chakravarthy et al., 2026). The human studies are in the next section.

• Lean mice, one dose — 6 nmol/kg cut body weight by about 10% against vehicle within 24 hours, with weight drifting back toward baseline by 96 hours, and reduced food intake (8 mice per group). Doses of 2–6 nmol/kg caused minimal conditioned taste aversion, while semaglutide at a dose matched for weight loss (20 nmol/kg) caused strong aversion (5–7 mice per group) (Chakravarthy et al., 2026).
• Diet-induced obese mice, 21 days — 6 nmol/kg a day lowered body weight by about 25% against vehicle (7 mice per group) and lowered liver weight (5 per group) (Chakravarthy et al., 2026).
• Genetically obese mice (MC4R knockout), 21 days — On 30 nmol/kg a day, weight fell about 20% from baseline while vehicle-treated mice gained about 8%, and food intake fell by about 41 g (43.5%) against vehicle; fasting glucose and insulin, fat-pad weight and liver weight were lower (5–6 mice per group) (Chakravarthy et al., 2026).
• Fatty-liver model mice, 8 weeks — In mice on a diet that produces liver changes like those of human steatohepatitis (MASH), 6 nmol/kg a day lowered body weight by about 20%, against 1% on vehicle, lowered the liver enzymes ALT and AST, and reduced liver fat, ballooned liver cells and the fatty-liver activity score (8–9 mice per group) (Chakravarthy et al., 2026).
• Monkeys, one dose — In lean cynomolgus monkeys, single doses of 0.15 or 0.5 mg/kg under the skin raised insulin and C-peptide and lowered blood glucose during an intravenous glucose test (4 monkeys per group) (Chakravarthy et al., 2026).

Human Data

Published in a peer-reviewed journal: one Phase 1 trial (Chakravarthy et al., 2026). Everything else comes from conference abstracts, Roche’s releases and slides, or trial registrations without posted results (ClinicalTrials.gov, searched October 4, 2026). Carmot or Roche sponsored every registered trial (ClinicalTrials.gov).

• Phase 1, single and weekly doses, 64 adults (Chakravarthy et al., 2026) — Randomized 3:1, double-blind and placebo-controlled (NCT04838405), in adults aged 18–65 with overweight or obesity and no diabetes. The single-dose part enrolled 40 adults at one site in Australia, 30 of whom got one dose of 0.5–7.5 mg; the weekly part enrolled 24 adults at one site in Mexico, 18 of whom got four weekly doses stepped up from 5 mg to 7.5 or 12 mg. After the four weekly doses, weight at day 29 was 4.1%, 5.6% and 7.5% lower than on placebo in the three cohorts, 7.4 kg in the highest, and the loss held for up to two weeks after the last dose. Fasting glucose fell 5.2–7.8 mg/dL against 0.2 mg/dL on placebo. The half-life, 123–151 hours, fits weekly dosing. A 2023 conference abstract on the same cohorts gave larger differences from placebo, 4.8%, 6.4% and 8.5% (Chakravarthy et al., 2023); the figures above are the paper’s. The authors list as limits single sites, small numbers, four weeks of treatment and no comparator drug. The registry lists 129 enrolled across all parts of the trial; the paper reports 64 of them (NCT04838405).
• Phase 1b, 24 weeks, 31 adults with obesity (Roche, May 16, 2024) — Another part of the same trial (NCT04838405) randomized 31 adults with obesity and no diabetes 4:1 to CT-388 stepped up to 22 mg once a week, or placebo (Steinberg et al., 2025, abstract 125-OR). Roche reported weight 18.8% lower than on placebo at week 24 (p < 0.001), with every participant on CT-388 losing more than 5% and 45% losing more than 20%, and said all those with prediabetes at the start had normal glucose by week 24 (Roche, May 16, 2024). A 2025 abstract gives the difference as 18.9% (95% CI 14–24%) and reports that, in the 27 with complete liver scans, liver fat fell 59% more than on placebo (Steinberg et al., 2025, abstract 125-OR). These results are not in a journal.
• Phase 1, 12 weeks, 19 adults with obesity and type 2 diabetes — A further cohort of the same trial (NCT04838405), randomized 4:1 to 22 mg once a week or placebo, on diet and exercise or metformin, with HbA1c of 7.0–10.0% at entry. HbA1c fell 3.0% against 0.2% on placebo and weight 8.6% against 1.2%; all 14 on CT-388 reached an HbA1c of 6.5% or less, and there were no serious adverse events or stops for adverse events (Steinberg et al., 2025, abstract 763-P). Conference abstract only.
• Phase 2 CT388-103, 48 weeks, adults without diabetes (NCT06525935) — Randomized, double-blind and placebo-controlled at 34 US sites, in adults aged 18–75 with a BMI of 30 or more, or 27 or more with a weight-related condition such as prediabetes or high blood pressure; the registry lists 469 enrolled. The 467 randomized were split equally between placebo and doses of 4, 8, 12, 16 or 24 mg, injected weekly at the study site; their mean age was 49, mean BMI 38, 68% were women and half had prediabetes (Lingvay et al., 2026; Roche, June 8, 2026). Doses were stepped up within the first 27 weeks to the highest dose each person tolerated, up to their group’s dose, and 4 mg was the least a person could take and stay in the study; 80% of the 24 mg group reached 24 mg (Roche, June 8, 2026). Estimated as if everyone had stayed on treatment, mean weight change at week 48 ran from −6.7% on 4 mg to −22.7% on 24 mg, against −0.2% on placebo, with no plateau on 24 mg; on that dose the difference from placebo was 22.5% on that basis and 18.3% counting everyone randomized (Lingvay et al., 2026; Roche, January 27, 2026; Roche, June 8, 2026). Of the 24 mg group who reached week 48, 47.8% had lost at least 20% and 26.1% at least 30%, and among those with prediabetes, 27 of 37 (73%) had normal glucose at week 48, against 3 of 40 (7.5%) on placebo (Lingvay et al., 2026; Roche, June 8, 2026). Roche adds that 54% on 24 mg ended with a BMI under 30, against 13% on placebo (Roche, January 27, 2026). The trial was funded by Carmot; its results are in an abstract, a poster and Roche releases, not a paper (Roche, June 8, 2026).
• Phase 2 CT-388-104, 48 weeks, 447 adults with type 2 diabetes (NCT06628362) — Randomized, double-blind and placebo-controlled, in adults with type 2 diabetes (HbA1c 7–10.5%) and a BMI of 25 or more, managed with diet and exercise, metformin or an SGLT-2 inhibitor (NCT06628362). Roche reported that both main goals were met: on 24 mg, estimated as if everyone had stayed on treatment, HbA1c fell 2.65% from a baseline of 8.1% (0.43% on placebo), and 4.13% in those who started above 8.5%; 90% reached an HbA1c of 6.5% or less and 62% under 5.7%; and weight fell 15.5% at 48 weeks (Roche, September 22, 2026; Roche, September 28, 2026). The registry lists week 36 for both main outcomes; Roche reports week 48 (NCT06628362; Roche, September 22, 2026). No results are posted or published.
• Phase 3 and other registered trials — ENITH-1 (about 2,000 adults with obesity or overweight and no type 2 diabetes) and ENITH-2 (about 1,600 with type 2 diabetes) compare three dosing regimens with placebo on weight change at week 72; both began in March 2026 at about 200 sites each, and participants inject the drug themselves with an integrated drug-device product (NCT07351045; NCT07351058). A Phase 3 in about 300 Chinese adults, with weight change at week 52 as its main result, and a Phase 1 in 36 healthy Chinese adults began in July 2026 (NCT07670416; NCT07626515). ZYNERGY, a Phase 2 of CT-388 with petrelintide, was not yet recruiting (NCT07589686). Roche plans Phase 3 trials in type 2 diabetes, one of them against tirzepatide, and in cardiovascular disease and heart failure, to start in the first half of 2027 (Roche, September 28, 2026).

The evidence meter on the CT-388 card reads “Human pilots”: it counts published human data on CT-388 itself, for fat loss, and the only peer-reviewed human study is the Phase 1 in 64 adults, of single doses or four weekly doses (Chakravarthy et al., 2026). The 48-week Phase 2 trials have so far been reported only in a conference abstract, slides and company releases (Lingvay et al., 2026; Roche, January 27, 2026; Roche, June 8, 2026; Roche, September 22, 2026; Roche, September 28, 2026).

Pipeline

• Phase 3 ENITH-1 (obesity or overweight without type 2 diabetes) (NCT07351045), primary completion est. Jul 2028
• Phase 3 ENITH-2 (obesity or overweight with type 2 diabetes) (NCT07351058), primary completion est. Aug 2028
• Phase 3 in Chinese adults with obesity or overweight, with or without type 2 diabetes (NCT07670416), primary completion est. Feb 2028
• Phase 2 ZYNERGY, with petrelintide (NCT07589686), primary completion est. Nov 2027
• Phase 1 in healthy Chinese adults (NCT07626515), primary completion est. May 2027

Reconstitution & Storage

No paper, trial record or company document read for this page describes CT-388 as a powder to reconstitute, or gives a vial strength, concentration, storage temperature or shelf life for the trial product, so there is no mixing table here. In the trials it was injected under the skin once a week (Chakravarthy et al., 2026; NCT06525935).

• How the trials gave it — In the obesity Phase 2, participants came to the study site every week for their dose (Roche, June 8, 2026). In the ENITH-1 and ENITH-2 Phase 3 trials, participants inject it themselves with an “integrated drug-device combination product” (NCT07351045; NCT07351058).
• Storage — No storage instructions for the trial product appear in the documents read for this page. A chemical supplier’s catalogue listing deposited in PubChem, labelled not for human use, gives −20 °C for up to a year for the powder (PubChem, 2026).
• Products outside the trials — What is sold is lab-reagent powder labelled for research use only (see Legal Status). No study has tested such a product in people, and no independent analysis of one has been published.

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Side Effects & Risks

• Nausea, vomiting and other stomach effects — In the 48-week obesity Phase 2, stomach and bowel problems were reported by 47–65% of participants across the CT-388 doses against 28% on placebo: nausea 33–46% against 19%, vomiting 8–25% against 0%, diarrhea 14–32% against 10% and constipation 22–26% against 8%, with participants grouped by the highest dose they reached (Roche, June 8, 2026). Roche says most were mild to moderate (Roche, January 27, 2026).
• Single doses in Phase 1 — One participant on 7.5 mg had moderate intractable vomiting, a serious event judged probably related to the drug; at 7.5 mg, 5 of 6 had nausea, 3 vomited, 3 had reflux and one had a Mallory-Weiss tear, a tear in the lining where the esophagus meets the stomach. One participant on 6 mg left the study after vomiting, diarrhea and abdominal pain, and one had a severe retinal detachment 7 days after a 6 mg dose, judged unrelated (Chakravarthy et al., 2026).
• Weekly doses in Phase 1 — No serious events and no one stopped for an adverse event. All 18 on CT-388 reported decreased appetite, and in the first weekly cohort all 6 had nausea and 5 vomited; nausea and vomiting were less common in the two later cohorts, which had higher body weights (Chakravarthy et al., 2026).
• Stopping treatment — In the obesity Phase 2, 5.9% of participants on CT-388 and 1.3% on placebo stopped because of adverse events (Roche, January 27, 2026): by dose group, 1% at 4 mg, 3% at 8 mg, 14% at 12 mg, 5% at 16 mg and 7% at 24 mg, against 1% on placebo (Roche, June 8, 2026). In the type 2 diabetes Phase 2, 2.0% on CT-388 and none on placebo stopped treatment because of adverse events (Roche, September 22, 2026). More people left the obesity trial’s placebo group for any reason (34%) than any CT-388 group (14–31%) (Roche, June 8, 2026).
• Serious adverse events — In the obesity Phase 2, 1–5% of participants across the CT-388 doses had a serious adverse event, against none on placebo, and no one died; Roche calls serious and grade 3 events low and not dose-dependent (Roche, June 8, 2026).
• Heart rate and blood pressure — In the Phase 1’s four-week weekly-dose part, heart rate in the fastest step-up cohort rose by a mean 15.8 beats per minute at day 29, against a fall of 5.5 on placebo; the authors call the rise transient. Systolic blood pressure fell 9.3 and 5.7 mmHg in two cohorts, against 0.3 on placebo, and ECGs showed no drug-related QTc change (Chakravarthy et al., 2026).
• Liver and other lab tests — One participant on a single 7.5 mg dose had ALT and AST above three times the upper limit of normal the day after dosing, back to baseline by day 8 without treatment; the paper reports no other clinically significant laboratory changes (Chakravarthy et al., 2026). In the weekly part, five people on CT-388 had mild laboratory adverse events (creatine phosphokinase up in two; ALT up, lactate dehydrogenase up and a longer clotting time in one each), none judged related to the drug (Chakravarthy et al., 2026).
• Low blood sugar — Roche reports no level 2 hypoglycemia in the type 2 diabetes Phase 2 (Roche, September 28, 2026).
• Warnings on the label of tirzepatide, the approved drug of the same class — Tirzepatide’s label carries a boxed warning that it causes thyroid C-cell tumors in rats, with unknown relevance to people, and lists severe stomach and bowel reactions, kidney injury from fluid loss, gallbladder disease, pancreatitis, serious allergic reactions, low blood sugar with insulin or insulin secretagogues, worsening diabetic eye disease and aspiration under anesthesia (Zepbound label). These are tirzepatide’s warnings; CT-388 has no label. The CT-388 obesity Phase 2 excluded people with a personal or family history of medullary thyroid cancer or a calcitonin of 20 ng/L or more (NCT06525935).
• What has not been tested — No animal toxicology study, drug-interaction study or study in pregnancy has been published (PubMed, searched October 4, 2026). The obesity Phase 2 excluded women who were pregnant or breastfeeding, and women who could become pregnant and were not using highly effective contraception (NCT06525935). No results beyond 48 weeks have been reported.
• WADA — CT-388 is not named on the 2026 Prohibited List. Section S0 prohibits at all times substances not addressed elsewhere on the List “with no current approval by any governmental regulatory health authority for human therapeutic use (e.g. drugs under pre-clinical or clinical development or discontinued…)” (World Anti-Doping Agency, 2026). No approval of CT-388 turned up for this page.

Bloodwork & Monitoring

No monitoring guidance for CT-388 has been published outside the trials, and there is no label. The trials measured these:

• Body weight and waist — Weight change was the main result of the obesity Phase 2 (NCT06525935); weight and hip and waist circumference were measured in Phase 1 (Chakravarthy et al., 2026).
• Blood sugar — Fasting glucose, insulin, HOMA-IR, HbA1c and an oral glucose tolerance test in Phase 1 (Chakravarthy et al., 2026); HbA1c as a main result in the type 2 diabetes Phase 2 (NCT06628362).
• Liver and kidney tests — ALT, AST, bilirubin, gamma-glutamyl transferase, alkaline phosphatase, creatinine and blood urea nitrogen in Phase 1 (Chakravarthy et al., 2026), and liver fat by MRI in the 24-week cohort (Steinberg et al., 2025, abstract 125-OR).
• Heart — Vital signs and ECGs (Chakravarthy et al., 2026).
• Calcitonin — A blood calcitonin of 20 ng/L or more kept people out of the obesity Phase 2 (NCT06525935).
• Which tests fit a given person — A question for a licensed healthcare provider. This page can’t answer it.

Commonly Stacked With

No study has tested CT-388 together with another compound on this site (PubMed and Europe PMC, searched October 4, 2026); in its type 2 diabetes trials it was given on top of diet and exercise, metformin or an SGLT-2 inhibitor (NCT06628362; Steinberg et al., 2025, abstract 763-P). Roche and Zealand Pharma plan a fixed-dose combination of CT-388 with petrelintide, Zealand’s amylin analog (Roche, March 12, 2025); the Phase 2 ZYNERGY trial plans to test the two together and each alone in an estimated 486 adults, and was not yet recruiting on October 4, 2026, so no results exist (NCT07589686).

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Legal Status

Related Compounds

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Next Steps

References

1. Chakravarthy MV, Rodriguez R, Hergarden A, Elliott MA, et al. Effects of CT-388, a once-weekly signaling-biased dual GLP-1/GIP receptor agonist, on weight loss and glycemic control in preclinical models and participants with obesity. Mol Metab. 2026;103:102291. PMID: 41319798. DOI: 10.1016/j.molmet.2025.102291. (Full text at PMC12771327, read October 4, 2026. Funded by Carmot Therapeutics, now part of Roche, which took part in the design, analysis and drafting.)
2. Chakravarthy M, Argüelles-Tello F, Sun A, Elliott M, et al. 75-LB: CT-388, a Novel Once-Weekly Dual GLP-1 and GIP Receptor Modulator, Is Safe, Well-Tolerated, and Produces More than 8% Weight Loss in Four Weeks in Overweight and Obese Adults. Diabetes. 2023;72(Supplement_1):75-LB. DOI: 10.2337/db23-75-lb. (Conference abstract.)
3. Steinberg A, Argüelles-Tello F, Zhu J, Wu J, et al. 125-OR: Effect of CT-388, a Signal-Biased Dual GLP-1/GIP Receptor Agonist, on Liver-Related MRI Parameters in Patients with Obesity. Diabetes. 2025;74(Supplement_1):125-OR. DOI: 10.2337/db25-125-or. (Conference abstract; cited as Steinberg et al., 2025, abstract 125-OR.)
4. Steinberg A, Argüelles-Tello F, Sánchez-Sánchez L, Ortiz W, et al. 763-P: Glycemic Control, Weight Reduction, and Safety with CT-388, a Signal-Biased Dual GLP-1/GIP Receptor Agonist—Results from a 12-Week Cohort in Adults with Obesity and Type 2 Diabetes. Diabetes. 2025;74(Supplement_1):763-P. DOI: 10.2337/db25-763-p. (Conference abstract; cited as Steinberg et al., 2025, abstract 763-P.)
5. Lingvay I, Jastreboff A, Lender D, Bays H, et al. 2813-LB: CT-388, a cAMP Signal-Biased GLP-1/GIP Receptor Agonist, Achieves Clinically Meaningful Weight Loss in People With Overweight/Obesity: A 48-Week Phase 2 Study. Diabetes. 2026;75(Supplement_1):2813-LB. DOI: 10.2337/db26-2813-lb. (Late-breaking conference abstract, ADA 2026.)
6. Rodriguez R, Hergarden A, Krishnan S, Morales M, et al. Biased agonism of GLP-1R and GIPR enhances glucose lowering and weight loss, with dual GLP-1R/GIPR biased agonism yielding greater efficacy. Cell Rep Med. 2025;6(6):102156. PMID: 40460831. DOI: 10.1016/j.xcrm.2025.102156. (Carmot’s mouse study of CT-859, a different molecule.)
7. Willard FS, Douros JD, Gabe MB, Showalter AD, et al. Tirzepatide is an imbalanced and biased dual GIP and GLP-1 receptor agonist. JCI Insight. 2020;5(17):e140532. PMID: 32730231. DOI: 10.1172/jci.insight.140532.
8. Jones B, Buenaventura T, Kanda N, Chabosseau P, et al. Targeting GLP-1 receptor trafficking to improve agonist efficacy. Nat Commun. 2018;9(1):1602. PMID: 29686402. DOI: 10.1038/s41467-018-03941-2.
9. Hinds CE, Peace E, Chen S, Davies I, et al. Abolishing β-arrestin recruitment is necessary for the full metabolic benefits of G protein-biased glucagon-like peptide-1 receptor agonists. Diabetes Obes Metab. 2024;26(1):65-77. PMID: 37795639. DOI: 10.1111/dom.15288.
10. Jepsen MM, Christensen MB. Emerging glucagon-like peptide 1 receptor agonists for the treatment of obesity. Expert Opin Emerg Drugs. 2021;26(3):231-243. PMID: 34176426. DOI: 10.1080/14728214.2021.1947240. (Review.)
11. Neumann J, Kirchefer U, Hofmann B, Gergs U. Future GLP-1 receptor co-agonists and their cardiac effects. Naunyn Schmiedebergs Arch Pharmacol. 2026. PMID: 42768195. DOI: 10.1007/s00210-026-05908-3. (Review.)
12. World Health Organization. Proposed International Nonproprietary Names: List 133. WHO Drug Information. 2025;39(2):515. Enicepatide: dual gastric inhibitory polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) receptor agonist, antidiabetic; C226H345FN48O67; CAS 2869147-44-2. cdn.who.int/media/docs/default-source/international-nonproprietary-names-(inn)/pl133.pdf. Read October 4, 2026.
13. FDA. Global Substance Registration System: Enicepatide, UNII MTP9QR7GYF (synthetic peptide, 38 residues, XEGTFTSDYSIXLDKIAQKAFVQWLIAGGPSSGAPPPS; residue 1 an N-capped β-alanine, residue 12 Aib, lysine 19 carrying a C20 diacid (icosanedioyl) on a γ-Glu and two-unit ethylene-glycol linker, serinamide end; names CT-388 and RO7795068; INN and USAN), and tirzepatide, UNII OYN3CCI6QE (39 residues, Aib at 2 and 13, the same lysine side chain at 20, serinamide end). gsrs.ncats.nih.gov. Read October 4, 2026.
14. Eli Lilly and Company. Zepbound (tirzepatide) injection prescribing information. DailyMed set ID 487cd7e7-434c-4925-99fa-aa80b1cc776b (version effective August 28, 2026): boxed warning, warnings and precautions (5.1–5.9), description (11) and mechanism of action (12.1). dailymed.nlm.nih.gov. Read October 4, 2026.
15. FDA. Drugs@FDA: tirzepatide, NDA 215866 (Mounjaro, first approved May 13, 2022) and NDA 217806 (Zepbound, first approved November 8, 2023), both Eli Lilly and Company, marketed by prescription. api.fda.gov/drug/drugsfda.json. Read October 5, 2026.
16. Roche. Roche enters into a definitive merger agreement to acquire Carmot Therapeutics, including three clinical stage assets with best-in-class potential in obesity and diabetes. Media release, December 4, 2023. roche.com/media/releases/med-cor-2023-12-04. Read October 4, 2026.
17. Roche. Roche reports positive Phase Ib results for its dual GLP-1/GIP receptor agonist CT-388 in people with obesity. Media release, May 16, 2024. roche.com/media/releases/med-cor-2024-05-16. Read October 4, 2026.
18. Roche. Roche enters into an exclusive collaboration & licensing agreement with Zealand Pharma to co-develop and co-commercialise petrelintide as a potential foundational therapy for people with overweight and obesity. Media release, March 12, 2025. roche.com/media/releases/med-cor-2025-03-12. Read October 4, 2026.
19. Roche. Roche announces positive Phase II results for its dual GLP-1/GIP receptor agonist CT-388 in people living with obesity. Media release, January 27, 2026. roche.com/media/releases/med-cor-2026-01-27. Read October 4, 2026.
20. Roche. Virtual ADA investor event, June 8, 2026: presentation, including the CT388-103 Phase 2 poster (Lingvay et al., 2813-LB) with its design, baseline, disposition, weight-change, normoglycemia and safety tables, and the CVRM pipeline slide. assets.roche.com/f/176343/x/20033a15c4/ada-ir-event_08-june-2026_final.pdf. Read October 4, 2026.
21. Roche. Roche announces positive Phase II results for dual GLP-1/GIP receptor agonist enicepatide in people living with type 2 diabetes and overweight or obesity. Media release, September 22, 2026. roche.com/media/releases/med-cor-2026-09-22. Read October 4, 2026.
22. Roche. Pharma Day 2026, September 28, 2026: presentation, Cardiovascular, Renal and Metabolism section (enicepatide Phase 2 results in obesity and type 2 diabetes; Phase 3 plans for 2027). assets.roche.com/f/176343/x/51deda2587/20260928_final_pharma-day-2026-publish-1.pdf. Read October 4, 2026.
23. ClinicalTrials.gov. Registrations of CT-388 (enicepatide, RO7795068): NCT04838405 (Phase 1, Carmot, 129 enrolled, completed August 2024), NCT06525935 (Phase 2, CT388-103, 469 enrolled, completed December 2025), NCT06628362 (Phase 2, CT-388-104, 447 enrolled, active, not recruiting), NCT07351045 (Phase 3 ENITH-1, about 2,000, recruiting), NCT07351058 (Phase 3 ENITH-2, about 1,600, recruiting), NCT07670416 (Phase 3 in China, about 300, recruiting), NCT07626515 (Phase 1 in China, 36, recruiting) and NCT07589686 (Phase 2 ZYNERGY with petrelintide, 486 planned, not yet recruiting). None posts results. clinicaltrials.gov, API v2. Read October 4, 2026.
24. FDA. FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss. Content current as of October 1, 2026. fda.gov/drugs/drug-alerts-and-statements/fdas-concerns-unapproved-glp-1-drugs-used-weight-loss. Read October 4, 2026.
25. PubChem. Substance records for enicepatide: SID 518139746 (FDA’s substance registration) and a chemical supplier’s catalogue listing (supplier not named), whose product page, read October 4, 2026, offers 10, 100 and 500 mg of solid, price on request, labelled “For research only, Do not use for Human!”, with storage of the powder at −20 °C for one year. pubchem.ncbi.nlm.nih.gov. Read October 4, 2026.
26. FDA. Drugs@FDA, NDC directory and drug labels (openFDA, api.fda.gov), NLM DailyMed, and FDA’s warning-letter search: searches for “enicepatide” and “CT-388,” October 4, 2026 (no records). European Medicines Agency. Medicines data table (ema.europa.eu, medicines-output-medicines_json-report), read October 4, 2026 (no entry).
27. Code of Federal Regulations. 21 CFR 216.23, bulk drug substances that can be used to compound drug products in accordance with section 503A, and 21 CFR 216.24, drug products withdrawn or removed from the market for reasons of safety or effectiveness. ecfr.gov. Read October 4, 2026.
28. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (categories 1–3). Updated May 14, 2026. fda.gov/media/94155/download.
29. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503B of the Federal Food, Drug, and Cosmetic Act (categories 1–3). Updated March 21, 2025. fda.gov/media/94164/download.
30. World Anti-Doping Agency. Prohibited List 2026 (in effect January 1, 2026). S0, Non-approved substances. wada-ama.org.
31. Searches of October 4, 2026: PubMed, “CT-388” (3 records: the developers’ paper and two reviews), “CT388” and “CT 388” (the same 3), “enicepatide,” “RO7795068” and “RG6640” (none); Europe PMC, “enicepatide” (1 record, a review-methods paper) and “CT-388” (45 hits; the only study of CT-388 itself is the developers’ paper); Crossref, CT-388 conference abstracts (four, in Diabetes, 2023–2026); ClinicalTrials.gov, “CT-388,” “CT388,” “RO7795068” and “enicepatide” (eight registrations, all sponsored by Carmot or Roche); PubMed, “CT-388” with petrelintide, semaglutide, tirzepatide or metformin (only the two reviews), with toxicology or toxicity (one review) and with interaction or pregnancy terms (none); Europe PMC, “CT-388” with petrelintide, semaglutide, tirzepatide or metformin, and with toxicology, pregnancy or drug-interaction terms (reviews only; no study of a combination, of toxicity, of interactions or in pregnancy); lab-reagent catalogues listing enicepatide for research use only (suppliers not named).

Related Research

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• PetrelintideAmylin Analog; planned combination with CT-388
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• RetatrutideGIP/GLP-1/Glucagon Triple Agonist