A long-acting amylin analogue given once weekly. Alone it produced up to 10.8% weight loss over 26 weeks against 3.0% on placebo [1]; the 20.4% figure people quote is the CagriSema combination with semaglutide, not cagrilintide on its own [3]. Not approved anywhere — the combination is under FDA review.
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Subcutaneous
Route
4 recommended
Sites
Once weekly
Frequency
Preparation
Bacteriostatic water (BAC water)
Insulin syringe (29-31 gauge, 0.5-1mL)
Alcohol swabs
Sterile vial of cagrilintide powder
Sharps container for safe needle disposal
Pro tip
Prepare all supplies on a clean surface before you begin. Having everything ready makes the process smoother and more sterile.
Mixing
Wash your hands thoroughly with soap and water. Gather all supplies on a clean, flat surface.
Remove the plastic cap from the peptide vial and wipe the rubber stopper with an alcohol swab. Let it air dry.
Draw the appropriate amount of bacteriostatic water into a sterile syringe.
Insert the needle into the vial at an angle, aiming at the inside wall of the vial. Slowly push the plunger to let the water trickle down the glass wall -- do NOT squirt directly onto the powder.
Once all water is added, gently swirl the vial in a slow circular motion. Never shake the vial, as this can damage the peptide bonds.
Continue swirling until the powder is completely dissolved and the solution is clear. If particles remain, let the vial sit for a few minutes and swirl again.
Label the vial with the date of reconstitution, the peptide name, and the concentration (e.g. 250mcg per 0.1mL).
Example calculation
5mg vial + 1mL BAC water = 5mg/mL concentration. Each 0.1mL (10 units) contains 0.5mg cagrilintide.
Dose calculation
For 2.4mg dose at 5mg/mL concentration: draw 0.48mL (48 units on insulin syringe). For easier math, many use 2mL water with 5mg vial for 2.5mg/mL.
Pro tip
Always add the bacteriostatic water slowly, letting it run down the side of the vial. Never shake the vial -- swirl gently to avoid damaging the peptide.
Location
Site 01
Abdomen
Pinch the skin 2 inches from navel. Avoid the area directly around the belly button. Rotate between left and right sides.
Site 02
Outer Thigh
Middle third of the outer thigh. Keep at least 4 inches above the knee and below the hip. Alternate legs each injection.
Site 03
Upper Arm
Back or outer area of the upper arm. This site may require assistance from another person for proper technique.
Site 04
Gluteal
Upper outer quadrant of the buttock. This site is best for intramuscular injections and larger volumes.
Rotate between 4 sites to prevent tissue buildup and ensure consistent absorption.
Pro tip
Rotate your injection sites with each dose to prevent lipohypertrophy (buildup of fatty tissue). Keep a simple log of where you last injected.
Step by step
Wash hands thoroughly and clean injection site with alcohol swab
Let the alcohol dry completely - this reduces stinging
Pinch the skin to create a fold for easier injection
Insert needle at a 45-90 degree angle depending on body composition
Inject the medication slowly over 5-10 seconds
Hold for 10 seconds before removing needle, then release skin
Pro tip
This peptide uses subcutaneous injection once weekly. Inject at a 45-90 degree angle into pinched skin. Aspirate before injecting to ensure you haven't hit a blood vessel.
Timing
Optimal timing
Best time
Same day each week, any time of day that works for your schedule
With food?
Can be taken with or without food - choose whatever is most convenient
Stacking notes
When combining with semaglutide (CagriSema), both can be injected on the same day. The combination is designed to be taken together for synergistic effects.
Sample daily schedule
One day a week, the same day each week
0.3 to 4.5 mg depending on the dose level — 2.4 mg in every phase 3 trial injection
Site: Subcutaneous; rotate sites
Weekly dosing is possible because the half-life is 159-195 hours [2]. No trial specified a time of day. Escalation to the target dose took up to 6 weeks alone [1], or 16 weeks of 4-week co-escalation steps when paired with semaglutide [2].
If combined with semaglutide
2.4 mg of each injection
Site: Separate injection sites
Every phase 3 trial of the combination used 2.4 mg of both drugs [3][6][7]. In REIMAGINE 2 a 1.0 mg + 1.0 mg combination was also tested [7]. The fixed-dose product is under FDA review and not approved.
Dosing tiers
Dose
0.3 mg
Frequency
Once weekly
Duration
26 weeks in the dose-finding trial
The lowest dose studied as monotherapy. Roughly 100 participants took it for 26 weeks; the cagrilintide groups as a whole lost 6.0% to 10.8% of body weight against 3.0% on placebo, with 0.3 mg at the bottom of that range [1]. Participants reached their assigned dose through an escalation period of up to 6 weeks; in the combination trials cagrilintide and semaglutide were co-escalated in 4-week steps over 16 weeks [2]. So there is a titration to your own target dose — there is not a ladder from one dose level to the next, because the dose groups ran in parallel and nobody crossed between them [1].
Dose
0.6 mg
Frequency
Once weekly
Duration
26 weeks in the dose-finding trial
A studied dose level, about 100 participants, 26 weeks [1]. Also one of the six cagrilintide doses tested alongside semaglutide 2.4 mg in the phase 1b trial [2].
Dose
1.2 mg
Frequency
Once weekly
Duration
26 weeks alone; 20 weeks in combination
In combination with semaglutide 2.4 mg this dose produced 15.7% weight loss at 20 weeks against 9.8% for semaglutide plus placebo — about 6 points of additional loss attributable to cagrilintide [2].
Dose
2.4 mg
Frequency
Once weekly
Duration
26 to 68 weeks depending on the trial
The dose that went forward. Every phase 3 trial uses 2.4 mg, both alone and as half of the fixed-dose CagriSema combination: REDEFINE 1 in 3,417 adults with obesity [3], REDEFINE 2 in 1,206 adults with type 2 diabetes [6], and REIMAGINE 2 in 2,713 people with type 2 diabetes, which carried a cagrilintide 2.4 mg monotherapy arm of 152 [7]. In the phase 1b trial 2.4 mg with semaglutide gave 17.1% weight loss at 20 weeks against 9.8% on semaglutide plus placebo [2]. Participants reached their assigned dose through an escalation period of up to 6 weeks; in the combination trials cagrilintide and semaglutide were co-escalated in 4-week steps over 16 weeks [2]. So there is a titration to your own target dose — there is not a ladder from one dose level to the next, because the dose groups ran in parallel and nobody crossed between them [1].
Dose
4.5 mg
Frequency
Once weekly
Duration
26 weeks in the dose-finding trial
The highest dose ever given to humans, and the top of the monotherapy dose-response: 10.8% weight loss (11.5 kg) at 26 weeks against 3.0% (3.3 kg) on placebo, and against 9.0% (9.6 kg) for liraglutide 3.0 mg — a 1.8 percentage point edge over liraglutide, p=0.03 [1]. It was not the dose taken into phase 3. A dedicated cardiac study escalated 53 healthy participants to 4.5 mg and found no clinically relevant QTc prolongation against placebo [8].
Preservation
Before mixing
Store in refrigerator at 36-46 degrees F (2-8 degrees C). Keep in original packaging to protect from light. Never freeze. Can tolerate brief room temperature exposure during shipping but return to refrigeration promptly.
After mixing
Refrigerate immediately after mixing with bacteriostatic water. Do not freeze reconstituted solution. Use within 28 days of first puncture. Keep vial upright to minimize contamination risk.
Shelf life after mixing
28 days
Signs of degradation
Discard the vial immediately if you notice any of these:
Cloudy or discolored solution (should be clear)
Visible particles, floaters, or clumps
Solution that has been accidentally frozen
Unusual smell when opening vial
Important
When to stop
Severe allergic reaction (rash, swelling, difficulty breathing)
Persistent severe nausea or vomiting not improving with dose reduction
Signs of pancreatitis (severe abdominal pain radiating to back)
Planned pregnancy or positive pregnancy test
Inability to maintain adequate nutrition despite dose adjustments
Any concerning symptoms your healthcare provider advises stopping for
Always consult your healthcare provider before stopping or modifying your dose. Do not stop abruptly without medical guidance, especially if you are also on diabetes medications.
Clean technique checklist
Wash hands thoroughly with soap and water before handling supplies
Swab vial tops and injection site with alcohol and let dry
Never touch the needle tip or allow it to contact non-sterile surfaces
Use a new syringe and needle for each injection
Dispose of used sharps in a proper sharps container
Store reconstituted peptides according to the storage instructions above
Published research
Lau DCW et al. · 2021
The dose-finding trial, and the source of every cagrilintide monotherapy dose. 906 adults without diabetes at 57 sites in ten countries were randomised 6:1 to once-weekly subcutaneous cagrilintide at 0.3, 0.6, 1.2, 2.4 or 4.5 mg (100-102 per dose group), once-daily liraglutide 3.0 mg (99), or placebo (101), for 26 weeks after a dose-escalation period of up to 6 weeks. These were PARALLEL dose groups, not a ladder anyone climbed. Weight fell 6.0% to 10.8% (6.4-11.5 kg) across the cagrilintide groups against 3.0% (3.3 kg) on placebo — a treatment difference of 3.0 to 7.8 percentage points, p<0.001. The top dose beat liraglutide 3.0 mg: 10.8% (11.5 kg) against 9.0% (9.6 kg), difference 1.8 percentage points, p=0.03. Gastrointestinal adverse events occurred in 41-63% of cagrilintide participants against 32% on placebo, nausea in 20-47% against 18%. 73 participants (10%) stopped treatment permanently, 30 (4%) because of adverse events.
Enebo LB et al. · 2021
The phase 1b combination trial, 95 adults exposed. Six sequential cohorts with a BMI of 27.0-39.9 were randomised 3:1 to once-weekly cagrilintide at 0.16, 0.30, 0.60, 1.2, 2.4 or 4.5 mg (n=11-12 each) or matched placebo (24), all on top of semaglutide 2.4 mg, with both drugs co-escalated in 4-week intervals over 16 weeks and no lifestyle intervention. At week 20, weight fell 15.7% on cagrilintide 1.2 mg and 17.1% on 2.4 mg against 9.8% on pooled placebo plus semaglutide — treatment differences of -6.0 (95% CI -9.9 to -2.0) and -7.4 (-11.2 to -3.5) percentage points. The 4.5 mg cohort fell 15.4% against 8.0% on its matched placebo. Note what the placebo arm here is: everyone received semaglutide 2.4 mg, so the 9.8% is semaglutide's own effect and cagrilintide added roughly 6-7 points on top. Of 566 adverse events in 92 participants, 207 (37%) were gastrointestinal. Cagrilintide's half-life was 159-195 hours, which is what makes weekly dosing possible.
Garvey WT et al. · 2025
REDEFINE 1, the phase 3a obesity trial. 3,417 adults without diabetes with a BMI of 30 or more, or 27 or more with an obesity-related complication, were randomised 21:3:3:7 to once-weekly cagrilintide-semaglutide 2.4 mg each (2,108), semaglutide 2.4 mg alone (302), cagrilintide 2.4 mg alone (302), or placebo (705), with lifestyle intervention, for 68 weeks. Body weight fell 20.4% on the combination against 3.0% on placebo (difference -17.3 percentage points, 95% CI -18.1 to -16.6, p<0.001), with more participants reaching 5%, 20%, 25% and 30% loss. Gastrointestinal adverse events affected 79.6% on the combination against 39.9% on placebo, mainly transient and mild to moderate. The 20.4% belongs to the combination; the cagrilintide-alone arm's own figure is not reported in the abstract.
Kruse T et al. · 2021
Describes the medicinal chemistry development of cagrilintide, explaining how lipidation extended the half-life from minutes (pramlintide) to approximately one week while maintaining receptor activity.
Frias JP et al. · 2023
In people with type 2 diabetes, CagriSema achieved 15.6% weight loss versus 5.1% with semaglutide alone over 32 weeks, with comparable HbA1c reductions and good tolerability.
Davies MJ, Bajaj HS, Broholm C, et al. · 2025
Phase 3a across 12 countries. 1,206 adults with type 2 diabetes and a BMI of 27 or more were randomised 3:1 to once-weekly cagrilintide-semaglutide, 2.4 mg of each (904), or placebo (302), with lifestyle intervention, for 68 weeks. Body weight fell 13.7% against 3.4% on placebo (difference -10.4 percentage points, 95% CI -11.2 to -9.5, p<0.001). HbA1c reached 6.5% or lower in 73.5% against 15.9% on placebo. Gastrointestinal adverse events were reported by 72.5% against 34.4% on placebo, most transient and mild to moderate.
Buse JB, Bajaj HS, Dalskov SM, et al. · 2026
The largest trial to carry a cagrilintide monotherapy arm. 2,713 people with type 2 diabetes in 30 countries were randomised across six groups for 68 weeks, including cagrilintide 2.4 mg alone (n=152) alongside cagrilintide-semaglutide 2.4 mg each (n=603), semaglutide 2.4 mg (n=605), the 1.0 mg combination (n=595), semaglutide 1.0 mg (n=609) and placebo (n=149). On the primary endpoint the 2.4 mg combination beat semaglutide 2.4 mg on HbA1c (-1.91 vs -1.75 percentage points; difference -0.16, 95% CI -0.27 to -0.05, p=0.0035) — a real but small separation. Adverse events: 86.9% (524/603) on the 2.4 mg combination, 82.2% (125/152) on cagrilintide alone, 81.2% (491/605) on semaglutide 2.4 mg, and 70.5% (105/149) on placebo, most commonly gastrointestinal.
Gabe MBN, Fuhr R, Sinn A, et al. · 2024
A dedicated cardiac-safety study in 105 healthy participants randomised to once-weekly subcutaneous cagrilintide escalated to 4.5 mg (n=53) or placebo (n=52), with oral moxifloxacin 400 mg as a positive control to prove the assay could detect a real signal. After the final 4.5 mg dose the upper limit of the two-sided 90% confidence interval for the placebo-adjusted QTcF change was below 10 ms at every timepoint, so the highest dose ever studied does not prolong cardiac repolarisation to a clinically relevant degree.
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