Once-weekly Skytrofa® lonapegsomatropin-tcgd
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Why SKYTROFA Photo Why SKYTROFA Photo

Why SKYTROFA

More than 10,000 patients and their doctors have chosen SKYTROFA for pediatric growth hormone deficiency.

Not an actual patient

SKYTROFA is the first and only FDA‑approved once-weekly growth hormone treatment that offers
a steady and predictable release of unmodified somatropin, which has the same structure as the growth hormone that the body would naturally produce.

Once-weekly SKYTROFA

  • Provides somatropin, the same structure as the growth hormone your body naturally produces.
  • Was designed to slowly release somatropin (active ingredient) over one week.
  • Has an established safety profile.

Learn about the SKYTROFA difference

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Once-weekly injections

Go from up to 7 injection days to just 1 injection day per week.

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No refrigeration

Store at room temperature for up to 6 months.*

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Preservative free

Each single-dose cartridge contains only lonapegsomatropin-tcgd, diluent, and sterile water.

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Proven efficacy

Reduction of percent of fat in the torso and increased lean body mass after just 38 weeks vs. placebo.†

* Store SKYTROFA in the original package to protect from light. Do not freeze. SKYTROFA can be stored at room temperature (not to exceed 86°F [30°C]) for up to 6 months. Alternatively, SKYTROFA can be stored under refrigeration at 36°F to 46°F (2°C to 8°C) until the expiration date. If refrigerated, keep at room temperature for 15 minutes before use. Do not use SKYTROFA beyond the expiration date or 6 months after the date it was first removed from refrigeration (whichever is earlier). † In a clinical trial that compared once-weekly SKYTROFA with placebo in 259 adults with adult growth hormone deficiency (aGHD) who previously had not been on treatment in the past 12 months. The primary endpoint from the trial was change from baseline in trunk percent fat (percent of fat in torso) at 38 weeks. The change in trunk percent fat was a 1.7% decrease from baseline. The secondary efficacy endpoints from the trial were greater increase in total body lean mass (+1.6 kg after 38 weeks) compared with placebo and greater reduction in trunk fat mass (-0.5 kg after 38 weeks) compared with placebo.

Chosen by more than

patients and their doctors, SKYTROFA is the #1 prescribed once-weekly treatment for pediatric GHD since 2021‡§

‡ Ascendis Pharma Endocrinology, Inc. Data on file; 2025. Numbers are based on Ascendis Signature Access Program (A·S·A·P) prescribing data as of September 24, 2025. §
Symphony Health, an ICON Company, Metys®, September 24, 2025.
SKYTROFA AI photo SKYTROFA AI photo

Meet the SKYTROFA Auto-Injector.
Offering automated mixing. No measuring.

The SKYTROFA Auto-Injector cartridges are pre-measured and ready to use, so you don’t have to calculate or adjust doses.

 

Your doctor will help you find the dose that’s right for you and adjust as needed.

Learn More

Provides an automated mixing step followed by a manual mixing step controlled by the device

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Safety and Results
Starting SKYTROFA

IMPORTANT SAFETY INFORMATION & USES

SKYTROFA is a prescription medicine used for:

  • the replacement of growth hormone in children 1 year old or older who weigh at least 26 pounds (11.5 kilograms) with growth hormone deficiency (GHD)
  • the replacement of growth hormone in adults with growth hormone deficiency (GHD)

Do not take SKYTROFA if:

  • you have a critical illness caused by certain types of heart or stomach surgery, trauma or breathing problems
  • you are allergic to somatropin or any of the ingredients in SKYTROFA
  • you are a child with closed bone growth plates
  • you have cancer or other tumors
  • you have certain types of eye problems caused by diabetes
  • you are a child with Prader-Willi syndrome who is severely obese or has breathing problems including sleep apnea (briefly stopping breathing during sleep)

Tell your healthcare provider if you are pregnant or plan to become pregnant, about all of your medical conditions, and about all the medicines you take. SKYTROFA may affect how other medicines work, and other medicines may affect how SKYTROFA works.

What are the possible side effects of SKYTROFA?

SKYTROFA may cause serious side effects, including:

  • serious allergic reactions. Get medical help right away if you have swelling of the face, mouth, tongue, or throat or trouble breathing
  • high risk of death in people who have critical illnesses caused by heart or stomach surgery, trauma, or serious breathing problems
  • increased risk of growth of an existing tumor or cancer, or increased risk of a previous tumor or cancer returning in people who were treated with radiation to the brain or head as children and who developed low growth hormone problems. Your healthcare provider will need to monitor for the growth or return of a tumor or cancer. Contact your healthcare provider if you start to have sudden changes in behavior, headaches, vision problems, or changes in moles, birthmarks, or skin color
  • new or worsening high blood sugar or diabetes. Your blood sugar may need to be monitored during treatment with SKYTROFA
  • increase in pressure in the skull. Contact your healthcare provider if headaches, eye problems, nausea, or vomiting occur
  • too much fluid in the body (fluid retention). Contact your healthcare provider if you notice swelling in the hands and feet, pain in the joints or muscles, or nerve
    problems that cause pain, burning or tingling in the hands, arms, legs, and feet
  • decrease in a hormone called cortisol. Your healthcare provider will do blood tests to check your cortisol levels
  • decrease in thyroid hormone levels. Decreased thyroid hormone levels may affect how well SKYTROFA works. Your healthcare provider will do blood tests to check your thyroid hormone levels
  • hip and knee pain or a limp in children (slipped capital femoral epiphysis). This may lead to a serious condition where bone tissue dies due to a lack of blood supply (osteonecrosis). Get medical help right away for children who develop a limp or have hip or knee pain
  • worsening of curvature of the spine in children (scoliosis)
  • severe and constant abdominal pain. This could be a sign of pancreatitis. Tell your healthcare provider about any new abdominal pain
  • loss of fat and tissue weakness in the area of skin you or your child inject. Talk to your healthcare provider about rotating the areas where SKYTROFA is injected
  • high risk of sudden death in children with Prader-Willi syndrome who are severely obese or have breathing problems, including sleep apnea
  • increase in phosphate, alkaline phosphatase, and parathyroid hormone levels in your blood. Your healthcare provider will do blood tests to check this

The most common side effects of SKYTROFA in children include: viral infection, fever, cough, nausea and vomiting, bleeding, diarrhea, stomach area pain, joint pain and arthritis

The most common side effects of SKYTROFA in adults include: swelling due to fluid build-up and low thyroid hormone

These are not all of the possible side effects of SKYTROFA. Call your doctor for medical advice about side effects. You are encouraged to report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. You may also report side effects to Ascendis Pharma at 1-844-442-7236.

Please click here for SKYTROFA full Prescribing Information.