Tesamorelin is the only growth hormone-releasing peptide with a current FDA approval, which means its dose and its side effects are written down in a prescribing label rather than pieced together from clinic pages. Everything below comes from that label and the phase 3 trials behind it. Readers comparing it with sermorelin will find the trial-by-trial contrast in the sermorelin vs. tesamorelin comparison; what follows is the label itself.
What is the approved tesamorelin dose?
It depends on which product is prescribed, because the two current versions are dosed differently. The label is explicit that EGRIFTA WR and EGRIFTA SV “are not substitutable” [2].
| EGRIFTA SV | EGRIFTA WR | |
|---|---|---|
| Daily dose | 1.4 mg (0.35 mL) | 1.28 mg (0.16 mL) |
| Vial | 2 mg, single dose | 11.6 mg, one patient |
| Mixed with | 0.5 mL sterile water | 1.3 mL bacteriostatic water |
| After mixing | Inject at once; discard the rest | Lasts 7 daily doses at room temperature |
Both are injected once a day, under the skin of the abdomen [1] [2]. The phase 3 trials that won approval used an older formulation at 2 mg a day [3]; the label states that side effects at the newer doses are expected to match those seen with that 2 mg dose [1]. There is no titration schedule and no weight-based dosing in the label: the dose is fixed.
How is tesamorelin injected and reconstituted?
For EGRIFTA SV, one vial is mixed with 0.5 mL of the sterile water supplied, rolled gently between the hands for 30 seconds rather than shaken, and 0.35 mL is injected straight away. Whatever is left is thrown out, and mixed solution is never refrigerated or saved [1]. EGRIFTA WR is mixed once a week with 1.3 mL of bacteriostatic water, swirled rather than shaken, and 0.16 mL is drawn each day for seven days, after which any remainder is discarded [2].
The injection goes into the abdomen, rotating between areas, and never into scar tissue, bruises or the navel. Unmixed vials are kept at room temperature, 68°F to 77°F, in the box to protect them from light [1] [2]. That is a practical difference from compounded sermorelin, which most compounding pharmacies say to refrigerate, as how to store sermorelin explains; the sermorelin injection technique guide covers the shot itself.
What are the most common side effects of tesamorelin?
The label lists six effects reported in more than 5% of patients: joint pain, injection-site redness, injection-site itching, pain in the arms or legs, swelling of the lower legs, and muscle pain [1]. Its trial table shows how much of each is the drug and how much would have happened anyway. Over the 26-week placebo-controlled phase, with 543 patients on tesamorelin and 263 on placebo:
- Any injection-site reaction: 17% vs. 6% on placebo
- Joint pain: 13% vs. 11%
- Muscle pain: 6% vs. 2%
- Lower-leg swelling: 6% vs. 2%
- Pain in the arms or legs: 6% vs. 5%
- Tingling (paresthesia): 5% vs. 2%
Many of these trace back to fluid retention, which the label ties to the extra growth hormone itself and describes as either transient or resolving when treatment stops [1]. Counting every kind of site reaction across the trials (redness, itching, pain, irritation, bruising), the rate was 25% vs. 14% on placebo, and rotating sites is the label’s advice for reducing them.
What are the serious warnings?
- IGF-1 rises, sometimes a lot. After 26 weeks, 47% of patients had IGF-1 more than two standard deviations above normal and 36% more than three. The label says the effects of prolonged elevation are unknown, asks prescribers to monitor IGF-1, and suggests stopping in patients with persistent elevations, especially if the response is weak [1].
- Blood sugar. HbA1c reached 6.5% or higher in 5% of tesamorelin patients vs. 1% on placebo, a hazard ratio of 3.3. The label calls for checking glucose before and during treatment, and for watching diabetic patients for worsening retinopathy [1].
- Hypersensitivity. Allergic-type reactions (itching, redness, flushing, hives, rash) occurred in 4% of treated patients.
- Critical illness. The label advises considering stopping tesamorelin in patients who become acutely critically ill, for example after major surgery or trauma.
It must not be used in pregnancy, in anyone with an active cancer, in people whose pituitary function has been disrupted by surgery, radiation, a tumor or head injury, or in anyone allergic to the drug [1]. How IGF-1 is tested applies to both drugs.
Does tesamorelin cause cancer?
The label does not say it causes cancer. It says growth hormone is a known growth factor, so tesamorelin must not be started in someone with an active malignancy, should be weighed carefully in anyone with a past cancer, and should be stopped if a cancer comes back. It also asks prescribers to consider the higher background cancer risk in people with HIV before starting [1]. That is a precaution about feeding an existing tumor, not a finding that the drug starts one. Sermorelin raises the same question for the same reason, which is covered in sermorelin’s side effects.
Who is tesamorelin approved for, and what is it not for?
One group: adults with HIV and lipodystrophy who have excess abdominal fat. The label adds three limits of its own. It is not indicated for weight loss, because its effect on body weight is neutral. Its long-term cardiovascular safety has not been established. And it should be reconsidered in anyone whose visceral fat has not fallen [1]. It is not approved for children, and the label has no information on patients over 65.
The trials explain both the approval and its narrowness. In the first phase 3 trial, 412 patients injecting tesamorelin daily for 26 weeks lost 15.2% of their visceral fat while the placebo group gained 5.0% [3]. Pooling both trials (n = 806), the treatment effect was a 15.4% reduction, with no meaningful change in the fat just under the skin [5]. The gains did not last without the drug: patients switched to placebo after six months rapidly lost the improvement [4]. Use outside this indication is off-label.
How does the tesamorelin dose compare with sermorelin’s?
On paper tesamorelin’s dose looks larger, but the two numbers do not line up. Tesamorelin is a fixed 1.28 or 1.4 mg a day. Sermorelin’s only adult trial dosed by body weight, 10 mcg per kilogram each night, which works out to 0.8 mg for an 80 kg adult; the dose-by-weight tool runs that arithmetic. They are different molecules, 44 amino acids against 29, so a milligram of one is not a milligram of the other, and no trial has compared them directly. What each dose is anchored to differs too: tesamorelin’s comes from an approval for a single condition, sermorelin’s from one 1997 trial. Where both sit among the other growth hormone peptides is mapped in growth hormone peptides.