Cagrilintide (5 mg vial)

Protocol Overview

Concise summary of the regimen.

Dosing & Reconstitution

Once weekly sub-Q, on the same day each week, using the ladder above. The acylation extends the half-life to roughly 160 to 195 hours, which is what makes a weekly cadence work and also means a step up does not show its full effect for two to three weeks; that lag is the reason each rung is held 2 weeks rather than changed on a single week of feedback. Injections go into subcutaneous tissue at the abdomen, thigh, or upper arm, with the site rotated every week to avoid lipohypertrophy. At the 5 mg/mL dilution used here the largest dose on the ladder is 90 units, so the whole protocol runs on a standard U-100 insulin syringe and no 3 mL syringe is needed; the tradeoff is that a 4.5 mg maintenance dose draws 0.90 mL, nearly the entire vial, so a maintenance week consumes close to one vial. Gradual escalation is the main tolerability lever, and holding a rung an extra 2 weeks is the usual response when gastrointestinal symptoms are still settling.

Results Timeline

Sequence described in the research record. Individual response varies.

• Weeks 1 to 6: titration in 2 week steps from 0.6 mg to 2.4 mg, the window where gastrointestinal symptoms such as nausea are most concentrated and generally most transient.
• Weeks 7 onward: maintenance at 4.5 mg weekly, held through the end of a 12 to 16 week run or longer where appropriate.
• Week 26: in the phase 2 dose finding trial, cagrilintide 4.5 mg weekly produced approximately 10.8% body weight loss versus 3.0% with placebo.
• Week 68: in the phase 3 REDEFINE program, cagrilintide combined with semaglutide 2.4 mg produced approximately 20% weight loss, exceeding either agent alone.

Reconstitution Steps

1. Draw 1.0 mL bacteriostatic water with a sterile syringe.
2. Inject slowly down the vial wall; avoid foaming or vigorous agitation.
3. Gently swirl or roll until fully dissolved (do not shake).
4. Label with date and concentration; refrigerate at 2 to 8 °C, protected from light. At 5 mg/mL, 1 unit = 0.01 mL » 50 mcg on a U-100 insulin syringe.
5. Use within 30 days of reconstitution; discard if the solution turns cloudy or if particulate matter appears. Ladder conversions at 5 mg/mL: 0.3 mg = 6 units; 0.6 mg = 12 units; 1.2 mg = 24 units; 2.4 mg = 48 units; 4.5 mg = 90 units.

Storage Instructions

Proper storage preserves peptide quality.

• Lyophilized: store at minus 20 °C (minus 4 °F) in dry, dark conditions, with moisture exposure kept to a minimum.
• Reconstituted: refrigerate at 2 to 8 °C (35.6 to 46.4 °F), use within 30 days, and avoid freeze thaw cycles.

• Allow vials to reach room temperature before opening, which reduces condensation uptake.
• Keep reconstituted vials on a shelf rather than in the refrigerator door, where temperature swings are largest, and label each one with date and concentration so a draw volume is never guessed.

Supplies Needed

Planning math is based on a weekly protocol of 8 to 16 weeks with titration every 2 weeks, finishing at 4.5 mg weekly.

Peptide Vials (Cagrilintide, 5 mg vial):

• A full 16 week course totals 53.4 mg, which is about 11 vials at 5 mg each; 12 weeks totals 35.4 mg, about 8 vials; 8 weeks totals 17.4 mg, about 4 vials.

Insulin Syringes (U-100):

• Per week: 1 U-100 insulin syringe, since at 5 mg/mL even the 4.5 mg maintenance dose is 90 units and fits a single syringe.
• Full cycle: 16 syringes over 16 weeks, 12 over 12 weeks, or 8 over 8 weeks, at one injection per week.

Bacteriostatic Water (10 mL bottles):

• Each 5 mg vial takes 1.0 mL, so one 10 mL bottle covers 10 vials: 1 bottle for an 8 or 12 week course and 2 bottles for the full 16 weeks.

Alcohol Swabs:

• Per injection: 2 swabs, one for the vial stopper and one for the skin.
• Full cycle: 32 swabs over 16 weeks, which one 100 count box covers with room to spare.

Important Notes

Practical considerations for consistency and safety.

• Use a new sterile syringe for every injection and dispose of it in a sharps container.
• Rotate injection sites weekly across abdomen, thighs, and upper arms to reduce local irritation.
• Gradual dose escalation is the main lever against gastrointestinal side effects such as nausea; repeating a rung for another 2 weeks is preferable to climbing through symptoms.
• At 5 mg/mL the entire ladder stays under 100 units, so the 3 mL syringe required at thinner dilutions is unnecessary here. Because a 4.5 mg dose is 0.90 mL, a maintenance week uses close to one full vial, and vial planning should follow that rather than the smaller titration draws.
• Logging the weekly dose, the injection site, and any adverse effects keeps the titration consistent and makes a tolerability problem visible before the next step up.
• Regulatory Note: cagrilintide is not an approved medicine and remains investigational, with its evidence base in phase 2 dose finding work and the phase 3 REDEFINE program in combination with semaglutide. Vials are research grade, not pharmaceutical grade, and the material here is educational and for research use only. WADA status is not addressed in the source material.

How This Works

Cagrilintide is an acylated, long acting analogue of amylin, a hormone co secreted with insulin from pancreatic beta cells. Native amylin promotes satiation, slows gastric emptying, and inhibits postprandial glucagon secretion, but it clears too quickly to be useful as a weekly injection. By acting on central amylin receptors, particularly in the area postrema and hindbrain, cagrilintide reduces appetite and energy intake, and the lipid modification extends its half-life to approximately 160 to 195 hours, which is what enables once weekly dosing. The result is continuous rather than meal linked satiety signaling, and that same continuous engagement of the hindbrain pathway is why the side effect profile is dominated by gastrointestinal symptoms during the climb.

Benefits & Side Effects

Observations from the published record.

• Weight reduction: in the phase 2 trial, cagrilintide 4.5 mg weekly produced approximately 10.8% body weight loss over 26 weeks versus 3.0% with placebo.
• Combination therapy: combined with semaglutide 2.4 mg as CagriSema, the phase 3 REDEFINE trials showed approximately 20% weight loss at 68 weeks, exceeding the result of either agent alone.
• Dose dependent efficacy: the higher doses of 2.4 to 4.5 mg demonstrate greater weight loss than the lower 0.3 to 1.2 mg band, which is the reason the ladder finishes where it does rather than stopping mid climb.
• Side effects: primarily gastrointestinal, including nausea, vomiting, diarrhea, and constipation, generally mild to moderate and transient. Gradual titration helps minimize them.
• Injection site reactions: occasional mild redness or irritation at subcutaneous injection sites.

Lifestyle Factors

Complementary strategies for best outcomes.

• Pair with a balanced, protein forward diet tailored to individual energy needs.
• Combine resistance training and aerobic activity to support metabolic health and preserve lean mass.
• Prioritize adequate sleep of 7 to 9 hours and stress management, both of which support adherence and recovery.
• Monitor hydration and electrolytes, particularly during any stretch of gastrointestinal side effects.

Injection Technique

General subcutaneous guidance from clinical best-practice resources.

1. Clean the vial stopper and skin with alcohol; allow to air dry completely.
2. Pinch a skinfold; insert the needle at 45 to 90 degrees into subcutaneous tissue.
3. Do not aspirate for subcutaneous injections; inject slowly and steadily.
4. Hold for 5 to 10 seconds before withdrawing the needle to ensure complete delivery.
5. Rotate sites systematically (abdomen, thighs, upper arms) each week to avoid lipohypertrophy.

References

Source citations for further reading.

1. Lau et al. Once-weekly cagrilintide for weight management: phase 2 dose-finding trial (The Lancet, 2021).
2. Cagrilintide phase 2 trial: 10.8% weight loss at 4.5 mg dose over 26 weeks (The Lancet, 2021).
3. REDEFINE 1: Coadministered cagrilintide and semaglutide in adults with overweight or obesity (NEJM, 2025).
4. Development of cagrilintide: a long-acting amylin analogue (J Med Chem, 2021).