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Skytrofa Dosage

Generic name: Lonapegsomatropin 3mg
Dosage form: injection, powder, lyophilized, for solution
Drug class: Growth hormones

Medically reviewed by Drugs.com. Last updated on Oct 28, 2022.

General Dosing Information

  • For subcutaneous injection, once-weekly.
  • Therapy with SKYTROFA should be supervised by a physician who is experienced in the diagnosis and management of pediatric patients with growth failure due to growth hormone deficiency (GHD).
  • To exclude preexisting papilledema, perform fundoscopic examination before initiating treatment with SKYTROFA and reassess periodically thereafter [see Warnings and Precautions (5.5)].

Dosage Recommendations

  • The recommended dose of SKYTROFA for treatment-naïve patients and patients switching from daily somatropin therapy is 0.24 mg/kg body weight, given once-weekly.
  • Individualize and titrate the dosage of SKYTROFA based on response.
  • When changing from daily somatropin therapy to once-weekly SKYTROFA, wait at least 8 hours between the final dose of daily somatropin and the first dose of once-weekly SKYTROFA.
  • Assess compliance and evaluate other causes of poor growth such as hypothyroidism, under-nutrition, advanced bone age and antibodies to recombinant human growth hormone if patients experience failure to increase height velocity, particularly during the first year of treatment.
  • Discontinue SKYTROFA once epiphyseal fusion has occurred.

Missed Doses

  • Administer a missed dose as soon as possible and not more than 2 days after the missed dose.
  • To avoid missed doses, SKYTROFA can be taken 2 days before or 2 days after the scheduled dosing day. Resume once-weekly dosing for the next dose at the previously scheduled dosing day.
  • If more than 2 days have passed from the scheduled day, skip the dose and administer the next dose on the regularly scheduled day.
  • At least 5 days should elapse between doses.

Administration Instructions

SKYTROFA is available in 9 cartridges (dosage strengths in somatropin equivalents). Selection of the appropriate cartridge is based on the prescribed dose (mg/kg) and the patient's body weight (kg).

  • If prescribing a dose of 0.24 mg/kg/week and the patient's weight is 11.5 to 100 kg, follow the recommended dosing in Table 1.
  • If prescribing a dose other than 0.24 mg/kg/week, calculate the total weekly dose (in mg) and select the appropriate cartridge as follows:
    Total weekly dose (mg) = prescribed weekly dose (mg/kg) × patient's body weight (kg).
    Round the total weekly dose (mg) to the closest cartridge dose while also considering treatment goals and clinical response.
Table 1: Recommended Dosing for Patients Prescribed Doses of 0.24 mg/kg/week
Weight (kg) Dose (mg)
11.5 – 13.9 3
14 – 16.4 3.6
16.5 – 19.9 4.3
20 – 23.9 5.2
24 – 28.9 6.3
29 – 34.9 7.6
35 – 41.9 9.1
42 – 50.9 11
51 – 60.4 13.3
60.5 – 69.9 15.2 (using two cartridges of 7.6 mg each)
70 – 84.9 18.2 (using two cartridges of 9.1 mg each)
85 – 100 22 (using two cartridges of 11 mg each)

Preparation and Administration

  • The SKYTROFA cartridge has been designed for use only with the SKYTROFA Auto-Injector.
  • If refrigerated, the SKYTROFA cartridge must be kept at room temperature for 15 minutes before use.
  • The SKYTROFA Auto-Injector provides a fully automated reconstitution of the lyophilized drug product which is followed by a manual mixing step controlled by the device. When the injection needle is inserted into the skin, the device automatically delivers the drug product. The built-in electronics and software assist the user during the entire preparation and injection sequence and provide confirmation that the full dose has been delivered.
  • The mixed solution should be clear and colorless to opalescent and may occasionally contain air bubbles. DO NOT inject if the solution is cloudy or contains particulate matter.
  • Use SKYTROFA cartridges within 4 hours after reconstitution. Discard reconstituted SKYTROFA cartridges after 4 hours when stored at room temperature up to 86°F (30°C).
  • Inject SKYTROFA subcutaneously into the abdomen, buttock, or thigh. Rotate injection sites between and within regions to reduce the risk of lipoatrophy.
  • Refer to the Instructions for Use for complete administration instructions with illustrations. The instructions can also be found on www.Skytrofa.com/IFU.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.