# Tesamorelin Dosing in the Research and Clinical Trials | Tesamorelin > Tesamorelin dosing in the trials: the 2 mg/day subcutaneous regimen used in both Phase 3 studies, the routes studied, the short plasma half-life, and the once-daily rationale. Research context, not advice. The regimens used in the published randomized trials, the route, the storage and pharmacokinetic constraints, and why dosing was once daily — described as research context, never as guidance. ## The short version In the trials, tesamorelin was given as a 2 mg injection under the skin once a day — that was the dose in both major Phase 3 studies and the FDA-approved regimen for the HIV use. The drug clears the blood fast (within about half an hour), but its downstream effect on IGF-1 (a growth signal) lasts through the day, which is why once daily worked. This page describes what was studied. It is not a dosing instruction, and the research-grade material discussed here is for laboratory study, not for people to inject. ## Dosing in the trials The extensively studied tesamorelin regimen is 2 mg subcutaneously once daily. That was the dose in both pivotal Phase 3 trials in HIV-associated lipodystrophy and the FDA-approved regimen [1][2][5]. A lower 1 mg/day arm has appeared in secondary studies, but the 2 mg once-daily paradigm is the one the visceral-fat efficacy data rest on. Later reformulations changed the concentration and presentation rather than the underlying once-daily logic; across the program, the extensively validated paradigm remains 2 mg once daily by subcutaneous injection. These are doses administered to a specific HIV-positive clinical-trial population under medical supervision — described here as research context, not as a recommendation. No human dosing instruction is given on this site, and the material discussed is research-grade tesamorelin supplied for laboratory use, not the approved finished drug. ## Route and administration as studied Subcutaneous injection — specifically at an abdominal site in the trials — is the only route studied in clinical trials and the only FDA-approved route [5]. There is no oral, intranasal, or transdermal tesamorelin in the trial record; the peptide would not survive gastrointestinal digestion intact, which is why every studied regimen used subcutaneous delivery. Tesamorelin is supplied as a lyophilized (freeze-dried) powder requiring reconstitution before use. The FDA prescribing information specifies refrigerated storage and use of the reconstituted solution within a defined window — constraints that reflect the peptide's physical instability once in solution [5]. ## Half-life and the once-daily rationale Tesamorelin clears the plasma quickly. Population PK modeling reported an apparent clearance around 1,060 L/h, and secondary sources describe a terminal half-life on the order of 26-38 minutes [11]. On its face, that brevity would argue against once-daily dosing. The resolution is the IGF-1 effect. Although the peptide itself is gone from the plasma within roughly half an hour, the IGF-1 elevation it triggers persists across the dosing interval, which is the pharmacodynamic basis for once-daily administration [11]. The trans-3-hexenoyl N-terminal modification is what makes even the brief plasma window possible, by blocking the DPP-IV cleavage that inactivates native GHRH almost immediately [6]. The full account is on the [mechanism page](/mechanism). ## Why the dose does not generalize The 2 mg once-daily regimen was validated in HIV patients with lipodystrophy — the only population with pivotal efficacy data [1][2]. There is no completed large randomized trial establishing a dose for general-population fat loss, anti-aging, or any non-HIV use, all of which are off-label [5]. Visceral fat also reaccumulated after discontinuation in the 52-week program, so the studied effect depended on continued dosing rather than a fixed course [2]. Anyone reading the dosing literature should treat the 2 mg figure as a documented trial parameter in a specific population, not a generalizable protocol — and the research-grade material discussed here is not for human use. For the [side effects and safety](/research) record, see the research page. --- The tesamorelin literature read as one procession of banner-marked findings -- the visceral-fat and IGF-1 trials carried back to their studies, the FDA-approved HIV-lipodystrophy scope held in the gold and every off-label use kept off-label, the reverts-when-you-stop and IGF-1 caveats flying their own pennants; an ornamented digest of the published evidence, never a clinic, a vendor, or a prescription.