Dr. Pep

Peptides · Long-acting amylin analogue

Cagrilintide: what the studies show

Every line below comes from a study, label or regulator record, checked by two models, with the source linked. Information, not medical advice. For adults 18+.

What it is

  • Cagrilintide is a long-acting lab-made copy of amylin, a hormone that makes people feel full. It is injected once a week under the skin. It is being developed by Novo Nordisk alone and in a fixed combination with semaglutide called CagriSema.[1][2]
  • Most recent trials test CagriSema, not cagrilintide alone. Results for the combination are mainly the effect of semaglutide plus cagrilintide together and should not be read as cagrilintide's own effect.[3][4]

Bottom line

  • Cagrilintide has good-quality randomised trial data for weight loss, mostly from the manufacturer, but it is not an approved drug. FDA says it cannot be used in compounding and has sent warning letters to sellers of 'research' cagrilintide.[1][3][5]

What the human studies found

  • Cagrilintide alone, phase 2 (double-blind RCT, 706 adults with obesity or overweight and no diabetes given cagrilintide, 99 given liraglutide 3.0 mg daily, 101 given placebo, 26 weeks): weight fell 6.0% to 10.8% on once-weekly cagrilintide 0.3 to 4.5 mg versus 3.0% on placebo. At 4.5 mg the loss was 10.8% versus 9.0% on liraglutide (p=0.03). The study was funded by Novo Nordisk.[1]
  • CagriSema, REDEFINE 1 (phase 3 double-blind RCT, 3,417 adults with obesity or overweight and no diabetes, 68 weeks, with lifestyle support): weight fell 20.4% on cagrilintide 2.4 mg plus semaglutide 2.4 mg versus 3.0% on placebo. Stomach and bowel side effects occurred in 79.6% versus 39.9%.[3]
  • CagriSema, REDEFINE 2 (RCT, 1,206 adults with obesity and type 2 diabetes, 68 weeks): weight fell 13.7% versus 3.4% on placebo. Stomach and bowel side effects occurred in 72.5% versus 34.4%.[4]
  • CagriSema versus semaglutide alone, East Asia (RCT, 331 randomised adults, 68 weeks): weight fell 18.4% versus 11.9% on semaglutide 2.4 mg.[6]
  • CagriSema, type 2 diabetes (RCT, 2,713 randomised adults on metformin, 68 weeks): the combination lowered blood sugar more than semaglutide alone, and the safety profile matched the GLP-1 drug class.[7]
  • Cagrilintide alone, pooled: a meta-analysis of four randomised trials (5,425 participants, listed in the records we hold as an RCT) reported weight loss of 6.08% for cagrilintide alone versus placebo, with large differences between trials.[8]

Known risks and side effects

  • Stomach and bowel side effects are the main problem. In the phase 2 trial, 41% to 63% on cagrilintide had them versus 32% on placebo, mostly nausea (20% to 47% versus 18%). About 10% across all groups stopped treatment, 4% because of side effects.[1]
  • Heart rhythm: in a thorough QT study (RCT, 105 adults, cagrilintide up to 4.5 mg versus placebo, moxifloxacin as a positive control), cagrilintide did not cause clinically relevant QTc lengthening.[9]
  • FDA says cagrilintide is not a component of any FDA-approved drug and has not been found safe and effective for any condition.[5]

Legal status

  • As of the FDA page updated in 2026, cagrilintide cannot be used in compounding under federal law, and it is not a component of an FDA-approved drug.[5]
  • FDA warning letters treated cagrilintide products sold online as unapproved new drugs: Xcel Research LLC and Summit Research Peptides (both 2024-12-10) and Prime Sciences (2026-03-31).[10][11][12]

Sources

  1. [1] Once-weekly cagrilintide for weight management in people with overweight and obesity: a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial.
  2. [2] Renal or Hepatic Impairment Does Not Affect Pharmacokinetics, Safety, or Tolerability of Subcutaneous Cagrilintide.
  3. [3] Coadministered Cagrilintide and Semaglutide in Adults with Overweight or Obesity.
  4. [4] Cagrilintide-Semaglutide in Adults with Overweight or Obesity and Type 2 Diabetes.
  5. [5] FDA: FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss (updated 2026)
  6. [6] Efficacy and safety of co-administered cagrilintide and semaglutide versus semaglutide alone in adults with overweight or obesity with or without type 2 diabetes in Japan and Taiwan (REDEFINE 5): a multicentre, randomised, active-controlled, phase 3a trial.
  7. [7] Cagrilintide-semaglutide (CagriSema) versus semaglutide or cagrilintide in people with type 2 diabetes (REIMAGINE 2): a double-blind, randomised, controlled, phase 3 study.
  8. [8] Amylin-based obesity therapy: a meta-analysis of Cagrilintide and CagriSema versus placebo.
  9. [9] Cagrilintide is not associated with clinically relevant QTc prolongation: A thorough QT study in healthy participants.
  10. [10] FDA: Warning Letter, Xcel Research LLC (2024-12-10), retatrutide, semaglutide, cagrilintide, survodutide, mazdutide, sermorelin
  11. [11] FDA: Warning Letter, Summit Research Peptides (2024-12-10), retatrutide, semaglutide, tirzepatide, cagrilintide, mazdutide
  12. [12] FDA: Warning Letter, Prime Sciences (2026-03-31), retatrutide, cagrilintide, mazdutide, semaglutide, tirzepatide