Peptide LibraryLonapegsomatropin dosage in published studies and labels
These are the doses used for Lonapegsomatropin in FDA labelling and published clinical studies, reported as each source states them, one row per regimen. They describe what was studied or approved for a specific population. They are not a recommendation, and none of them is a dose for any individual.
Research and educational reference only. This is not medical advice, and no figure on this page is a dosing recommendation.
Last checked against primary sources:
Studied regimens and sources
Lonapegsomatropin has FDA-approved human dosages as Skytrofa, given by subcutaneous injection once a week. Children aged 1 year and older who weigh at least 11.5 kg and have growth failure due to inadequate growth hormone secretion receive 0.24 mg/kg once weekly. Adults with growth hormone deficiency start at 0.7, 1.4 or 2.1 mg once weekly depending on age and oral oestrogen use, titrated monthly to at most 6.3 mg once weekly. Doses are stated in somatropin equivalents.
| Human dosing established | Yes |
|---|---|
| Route | Subcutaneous |
| Frequency | Once weekly |
| Duration studied | Continuous |
| Titration | Adults: start at 1.4 mg once weekly at ages 30–60 without oral oestrogen, 2.1 mg under age 30 or at any age with oral oestrogen, and 0.7 mg over age 60 without oral oestrogen; move up a cartridge strength monthly by clinical response and serum IGF-1 drawn 4–5 days after a dose; maximum 6.3 mg once weekly. Children: 0.24 mg/kg once weekly, individualised by response. |
| Half-life | Mean observed half-life of about 30.7 hours for lonapegsomatropin and about 25 hours for the somatropin it releases, in children with growth hormone deficiency (Skytrofa label) |
| Evidence level | FDA Approved |
| Last reviewed | 2026-11-07 |
Research-reported dosing
Doses as studied, one row per regimen. Different trials used different regimens; they are listed separately rather than averaged.
| Study / context | Population | Dose | Route | Frequency | Duration | Outcome studied | Source |
|---|---|---|---|---|---|---|---|
| FDA label — Skytrofa, paediatric growth hormone deficiencyFDA-approved label · FDA prescribing information | Children aged 1 year and older weighing at least 11.5 kg with growth failure due to inadequate secretion of endogenous growth hormone | 0.24 mg/kg (somatropin equivalent); the label's table gives cartridge doses from 3 mg at 11.5–13.9 kg to 22 mg at 85–100 kg | Subcutaneous, abdomen, buttock or thigh, rotating sites | Once weekly | Individualised by growth response | In the label's 52-week phase 3 study (161 treatment-naive prepubertal children), annualised height velocity was 11.2 cm/year with Skytrofa and 10.3 cm/year with daily somatropin at the same weekly dose of 0.24 mg/kg | SKYTROFA (lonapegsomatropin-tcgd) for injection — FDA prescribing information, DailyMed |
| FDA label — Skytrofa, adult growth hormone deficiencyFDA-approved label · FDA prescribing information | Adults with growth hormone deficiency | 0.7, 1.4 or 2.1 mg to start depending on age and oral oestrogen use; maximum 6.3 mg (somatropin equivalent) | Subcutaneous | Once weekly | Continuous; titrated monthly against clinical response and serum IGF-1 | Replacement of endogenous growth hormone | SKYTROFA (lonapegsomatropin-tcgd) for injection — FDA prescribing information, DailyMed |
Where sources disagree
- Lonapegsomatropin is a prodrug: somatropin is attached to a polyethylene glycol carrier by a linker that releases it over the week. Skytrofa doses are written in milligrams of somatropin equivalent, so they are not milligrams of the whole prodrug molecule.
- Skytrofa comes as single-dose dual-chamber cartridges (0.7 mg to 13.3 mg) used only with the Skytrofa Auto-Injector, which mixes the powder with its water automatically. The label does not describe reconstitution by hand.
- When switching from daily somatropin the label asks for at least 8 hours between the last daily dose and the first Skytrofa dose, and at least 7 days when switching from another once-weekly growth hormone. Once-weekly growth hormone products are not interchangeable dose for dose.