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skytrofa

Skytrofa (Lonapegsomatropin-Tcgd) is a medication used to treat Septo-Optic Dysplasia.

Lonapegsomatropin-Tcgd · by Ascendis Pharma Encocrinology Div A/S

Not yet rated· sourced from the FDA label
Rated against independent regulatory sources·Last updated June 7, 2026·How we rate
Verified againstopenFDANIH DailyMedRxClass

Key facts

Active ingredient
Lonapegsomatropin-Tcgd
Form
Injectable
Strength
LONAPEGSOMATROPIN-TCGD 11MG · LONAPEGSOMATROPIN-TCGD 13.3MG · LONAPEGSOMATROPIN-TCGD 3.6MG · LONAPEGSOMATROPIN-TCGD 3MG · LONAPEGSOMATROPIN-TCGD 4.3MG · LONAPEGSOMATROPIN-TCGD 5.2MG · LONAPEGSOMATROPIN-TCGD 6.3MG · LONAPEGSOMATROPIN-TCGD 7.6MG · LONAPEGSOMATROPIN-TCGD 9.1MG
Type
Prescription (Rx)
Brand or generic
Brand-name
FDA application
BLA761177

What is Skytrofa?

From the FDA label:Lonapegsomatropin-tcgd is a long-acting prodrug of a human growth hormone (somatropin) produced by recombinant DNA technology using E. coli . Lonapegsomatropin-tcgd consists of a parent drug, somatropin, that is conjugated to a methoxypolyethylene glycol carrier (4 × 10 kDa mPEG) via a proprietary TransCon Linker and has a molecular weight of 63 kDa (released somatropin is 22 kDa). In vitro assay confirms the minimum potency of released somatropin is NLT 2.5 IU/mg. SKYTROFA (lonapegsomatropin-tcgd) for injection is a sterile, preservative-free, white to off-white lyophilized powder available in a single-dose, dual-chamber, prefilled cartridge containing lonapegsomatropin-tcgd in one chamber and the diluent, Water for Injection, in the other chamber. SKYTROFA prefilled cartridge must be used with SKYTROFA Auto-Injector to provide an automatic mixing step for reconstitution prior to subcutaneous use. After reconstitution, each prefilled cartridge delivers: 0.327 mL containing 0.7 mg lonapegsomatropin-tcgd, succinic acid (0.39 mg), trehalose dihydrate (29.8 mg) and tromethamine for pH adjustment to 5.0. 0.327 mL containing 1.4 mg lonapegsomatropin-tcgd, succinic acid (0.39 mg) trehalose dihydrate (29.1 mg) and tromethamine for pH adjustment to 5.0. 0.327 mL containing 1.8 mg lonapegsomatropin-tcgd, succinic acid (0.39 mg) trehalose dihydrate (28.8 mg) and tromethamine for pH…

How to use

SKYTROFA should be administered subcutaneously once weekly into the abdomen, buttock, or thigh with regular rotation of the injection sites ( 2.7 ). Pediatric Patients: Recommended dose is 0.24 mg/kg body weight once weekly ( 2.2 ). Adults: Recommended starting dose is based on age and concomitant use of oral estrogen. Titrate monthly until the desired clinical response and/or weekly average IGF-1 concentration are achieved ( 2.3 ). See Full Prescribing Information for instructions on preparation and administration of drug ( 2.5 , 2.6 , 2.7 ). 2.1 General Dosing Information For subcutaneous injection, once weekly. Therapy with SKYTROFA should be supervised by a healthcare provider who is experienced in the diagnosis and management of patients with growth hormone deficiency (GHD). Perform fundoscopic examination before initiating treatment with SKYTROFA to exclude preexisting papilledema. If papilledema is identified, evaluate the etiology and treat the underlying cause before initiating treatment with SKYTROFA [see Warnings and Precautions (5.5) ] . 2.2 Recommended Dosage for Pediatric Patients The recommended dose of SKYTROFA for treatment-naïve patients and patients switching from another growth hormone product 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…

Side effects

The following important adverse reactions are described elsewhere in the labeling: Increased mortality in patients with acute critical illness [see Warnings and Precautions (5.1) ] Severe hypersensitivity [see Warnings and Precautions (5.2) ] Increased risk of neoplasms [see Warnings and Precautions (5.3) ] Glucose intolerance and diabetes mellitus [see Warnings and Precautions (5.4) ] Intracranial hypertension [see Warnings and Precautions (5.5) ] Fluid retention [see Warnings and Precautions (5.6) ] Hypoadrenalism [see Warnings and Precautions (5.7) ] Hypothyroidism [see Warnings and Precautions (5.8) ] Slipped capital femoral epiphysis in pediatric patients [see Warnings and Precautions (5.9) ] Progression of preexisting scoliosis in pediatric patients [see Warnings and Precautions (5.10) ] Pancreatitis [see Warnings and Precautions (5.11) ] Lipoatrophy [see Warnings and Precautions (5.12) ] Sudden death in pediatric patients with Prader-Willi syndrome [see Warnings and Precautions (5.13) ] Pediatric Patients: Most common adverse reactions (≥ 5%): viral infection, pyrexia, cough, nausea and vomiting, hemorrhage, diarrhea, abdominal pain, and arthralgia and arthritis ( 6.1 ). Adults: Most common adverse reaction (≥ 5%): edema peripheral ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Ascendis Pharma Endocrinology, Inc., at 1-844-442-7236 or FDA at 1-800-FDA-1088 or…

Warnings

Important safety information

Severe Hypersensitivity: Hypersensitivity reactions, including anaphylaxis and angioedema have occurred. In the event of an allergic reaction, seek prompt medical attention ( 5.2 ). Increased Risk of Neoplasms: Monitor patients with preexisting tumors for progressions or recurrence. Increased risk of a second neoplasm in childhood cancer survivors treated with somatropin – in particular meningiomas in patients treated with radiation to the head for their first neoplasm ( 5.3 ). Glucose Intolerance and Diabetes Mellitus: May be unmasked. Periodically monitor glucose levels in all patients. Doses of concurrent antihyperglycemic drugs in diabetics may require adjustment ( 5.4 ). Intracranial Hypertension: Exclude preexisting papilledema. May develop and is usually reversible after discontinuation or dose reduction ( 5.5 ). Fluid Retention (i.e., edema, arthralgia, carpal tunnel syndrome): May occur. Reduce dose as necessary ( 5.6 ). Hypoadrenalism: Monitor patients for reduced serum cortisol levels and/or need for glucocorticoid dose increases in those with known hypoadrenalism ( 5.7 ). Hypothyroidism: May first become evident or worsen ( 5.8 ). Slipped Capital Femoral Epiphysis in Pediatric Patients: May develop. Evaluate children with the onset of a limp or persistent hip/knee pain ( 5.9 ). Progression of Preexisting Scoliosis: May develop ( 5.10 ). Pancreatitis: Consider pancreatitis in patients with persistent severe abdominal pain ( 5.11 ). 5.1 Increased Mortality in Patients With Acute Critical Illness Increased mortality in patients with acute critical illness due to complications following open heart surgery, abdominal surgery or multiple accidental trauma, or those with acute respiratory failure has been reported after treatment with pharmacologic doses of somatropin [see Contraindications (4) ]. The safety of continuing SKYTROFA treatment in patients receiving replacement doses for the approved indication who concurrently develop these illnesses has not been established. 5.2 Severe Hypersensitivity Severe systemic hypersensitivity reactions, including anaphylactic reactions and angioedema have been reported with postmarketing use of somatropin products, including SKYTROFA. Inform patients and/or caregivers that such reactions are possible, and that prompt medical attention should be sought if an allergic reaction occurs. SKYTROFA is contraindicated in patients with known hypersensitivity to somatropin or any of the excipients in SKYTROFA. 5.3 Increased Risk of Neoplasms Active Malignancy There is an increased risk of malignancy progression with somatropin treatment in patients with active malignancy [see Contraindications (4) ]. Any preexisting malignancy should be inactive, and its treatment should be completed prior to instituting therapy with SKYTROFA. Discontinue SKYTROFA if there is evidence of recurrent malignancy. Risk of Second Neoplasm in Pediatric Patients In childhood cancer survivors who were treated with radiation to the brain/head for their first neoplasm and who developed subsequent growth hormone deficiency (GHD) and were treated with somatropin, an increased risk of a second neoplasm has been reported. Intracranial tumors, in particular meningiomas, were the most common of these second neoplasms. Monitor all patients with a history of GHD secondary to an intracranial neoplasm while on somatropin therapy for progression or recurrence of the tumor. New Malignancy During Treatment Because children with certain rare genetic causes of short stature have an increased risk of developing malignancies, thoroughly consider the risks and benefits of starting somatropin in these patients. If treatment with somatropin is initiated, carefully monitor these patients for development of neoplasms. Monitor patients on SKYTROFA therapy carefully for increased growth or potential malignant changes of preexisting nevi. Advise patients/caregivers to report marked changes in behavior, onset of headaches, vision disturbances and/or changes in skin pigmentation or changes in the appearance of preexisting nevi. 5.4 Glucose Intolerance and Diabetes Mellitus Treatment with somatropin may decrease insulin sensitivity, particularly at higher doses. Previously undiagnosed impaired glucose tolerance and overt type 2 diabetes mellitus may be unmasked. Monitor glucose levels in all patients receiving SKYTROFA, especially in those with risk factors for type 2 diabetes mellitus, such as obesity or a family history of type 2 diabetes mellitus. When initiating SKYTROFA, monitor closely patients with preexisting type 1 or type 2 diabetes mellitus or impaired glucose tolerance and adjust the doses of antihyperglycemic drugs as needed. 5.5 Intracranial Hypertension Intracranial hypertension (IH) with papilledema, visual changes, headache, nausea, and/or vomiting has been reported in a small number of patients treated with somatropin. Symptoms usually occurred within 8 weeks after the initiation of somatropin. In all reported cases, IH-associated signs and symptoms resolved rapidly after cessation of therapy or a reduction of the somatropin dose. To exclude preexisting papilledema, perform fundoscopic examination before initiating treatment with SKYTROFA, and reassess periodically thereafter. If papilledema is observed by fundoscopy, stop somatropin treatment. If somatropin-induced IH is confirmed, restart treatment with SKYTROFA at a lower dose after IH-associated signs and symptoms have resolved. 5.6 Fluid Retention Fluid retention during somatropin therapy may occur. Clinical manifestations of fluid retention (e.g., edema, arthralgia, myalgia, nerve compression syndromes, including carpal tunnel syndrome/paresthesia) are usually transient and dose dependent. 5.7 Hypoadrenalism Patients receiving somatropin therapy who have or are at risk for pituitary hormone deficiency(s) may be at risk for reduced serum cortisol levels and/or unmasking of central (secondary) hypoadrenalism. In addition, patients treated with glucocorticoid replacement for previously diagnosed hypoadrenalism may require an increase in their maintenance or stress doses following initiation of SKYTROFA therapy. Monitor patients for reduced serum cortisol levels and/or need for glucocorticoid dose increases in patients with known hypoadrenalism [see Drug Interactions (7) ] . 5.8 Hypothyroidism Undiagnosed or untreated hypothyroidism may prevent optimal response to SKYTROFA. In patients with GHD, central (secondary) hypothyroidism may first become evident or worsen during SKYTROFA treatment. Therefore, perform periodic thyroid function tests in patients and initiate or appropriately adjust thyroid hormone replacement therapy when indicated. 5.9 Slipped Capital Femoral Epiphysis in Pediatric Patients Slipped capital femoral epiphysis may occur more frequently in patients undergoing rapid growth. Slipped capital femoral epiphysis may lead to osteonecrosis. Cases of slipped capital femoral epiphysis with or without osteonecrosis have been reported in pediatric patients with short stature receiving somatropin. Evaluate pediatric patients receiving SKYTROFA with the onset of a limp or complaints of persistent hip or knee pain for slipped capital femoral epiphysis and osteonecrosis and manage accordingly. 5.10 Progression of Preexisting Scoliosis in Pediatric Patients Somatropin increases growth rate in pediatric patients, and progression of existing scoliosis can occur in patients who experience rapid growth. Somatropin has not been shown to increase the occurrence of scoliosis. Monitor patients with a history of scoliosis for disease progression. 5.11 Pancreatitis Pancreatitis has been reported in pediatric patients receiving somatropin. The risk may be greater in pediatric patients than adults. Consider pancreatitis in patients who develop persistent severe abdominal pain. 5.12 Lipoatrophy When SKYTROFA is administered subcutaneously at the same site over a long period of time, lipoatrophy may result.…

Who should not take Skytrofa

SKYTROFA is contraindicated in patients with: Acute critical illness after open heart surgery, abdominal surgery or multiple accidental trauma, or those with acute respiratory failure due to the risk of increased mortality with use of pharmacologic doses of somatropin [see Warnings and Precautions (5.1) ] . Hypersensitivity to somatropin or any of the excipients in SKYTROFA. Severe systemic hypersensitivity reactions, including anaphylactic reactions and angioedema, have been reported [see Warnings and Precautions (5.2) ]. Pediatric patients with closed epiphyses. Active malignancy due to the risk of malignancy progression [see Warnings and Precautions (5.3) ]. Active proliferative or severe non-proliferative diabetic retinopathy because treatment with somatropin may worsen this condition. Pediatric patients with Prader-Willi syndrome who are severely obese, have a history of upper airway obstruction or sleep apnea or have severe respiratory impairment due to the risk of sudden death [see Warnings and Precautions (5.13) ]. Acute critical illness ( 4 ) Hypersensitivity to somatropin or any of the excipients in SKYTROFA ( 4 ) Children with closed epiphyses ( 4 ) Active malignancy ( 4 ) Active proliferative or severe non-proliferative diabetic retinopathy ( 4 ) Children with Prader-Willi syndrome who are severely obese or have severe respiratory impairment due to risk of sudden death ( 4 )

Overdose — what happens if you take too much

Acute overdosage may lead initially to hypoglycemia and subsequently to hyperglycemia. Overdose with somatropin may cause fluid retention. Long-term overdosage may result in signs and symptoms of gigantism consistent with the known effects of excess growth hormone.

U.S. Poison Control: call or text 1-800-222-1222 (free, 24/7). In an emergency call 911. From the FDA label; not medical advice.

Interactions

Table 4 includes a list of drugs with clinically important drug interactions when administered concomitantly with SKYTROFA and instructions for preventing or managing them. Table 4: Clinically Important Drug Interactions with SKYTROFA Replacement Glucocorticoid Treatment Clinical Impact: Microsomal enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD-1) is required for conversion of cortisone to its active metabolite, cortisol, in hepatic and adipose tissue. Somatropin inhibits 11βHSD-1. Consequently, individuals with untreated growth hormone deficiency (GHD) have relative increases in 11βHSD-1 and serum cortisol. Initiation of SKYTROFA may result in inhibition of 11βHSD-1 and reduced serum cortisol concentrations. Intervention: Patients treated with glucocorticoid replacement for hypoadrenalism may require an increase in their maintenance or stress doses following initiation of SKYTROFA [see Warnings and Precautions (5.7) ] Examples Cortisone acetate and prednisone may be affected more than others because conversion of these drugs to their biologically active metabolites is dependent on the activity of 11βHSD-1. Pharmacologic Glucocorticoid Therapy and Supraphysiologic Glucocorticoid Treatment Clinical Impact: Pharmacologic glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth-promoting effects of SKYTROFA in pediatric patients. Intervention: Carefully adjust glucocorticoid replacement dosing in pediatric patients receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth. Cytochrome P450-Metabolized Drugs Clinical Impact: Limited published data indicate that somatropin treatment increases cytochrome P450 (CYP450)-mediated antipyrine clearance. SKYTROFA may alter the clearance of compounds known to be metabolized by CYP450 liver enzymes. Intervention: Careful monitoring is advisable when SKYTROFA is administered in combination with drugs metabolized by CYP450 liver enzymes. Oral Estrogen Clinical Impact: Oral estrogens may reduce the serum insulin-like growth factor-1 (IGF-1) response to SKYTROFA. Intervention: Patients receiving oral estrogen replacement may require higher SKYTROFA dosages. Insulin and/or Other Antihyperglycemic Agents Clinical Impact: Treatment with SKYTROFA may decrease insulin sensitivity, particularly at higher doses. Intervention: Patients with diabetes mellitus may require adjustment of their doses of insulin and/or other antihyperglycemic agents [see Warnings and Precautions (5.4) ] . Replacement Glucocorticoid Treatment: Patients treated with glucocorticoid for hypoadrenalism may require an increase in their maintenance or stress doses following initiation of SKYTROFA ( 7 ). Pharmacologic Glucocorticoid Therapy and Supraphysiologic Glucocorticoid Treatment: Adjust glucocorticoid dosing in pediatric patients to avoid both hypoadrenalism and an inhibitory effect on growth ( 7 ). Cytochrome P450-Metabolized Drugs: SKYTROFA may alter the clearance. Monitor carefully if used with SKYTROFA ( 7 ). Oral Estrogen: Larger doses of SKYTROFA may be required ( 7 ). Insulin and/or Other Antihyperglycemic Agents: Dose adjustment of insulin or antihyperglycemic agent may be required ( 7 ).

Storing Skytrofa, and how long it keeps

Quoted from this product’s own FDA label. Storage belongs to the product and its device, not to the drug in general — a pen and a tablet of the same medicine are kept completely differently.

  • Discard reconstituted SKYTROFA cartridges after 4 hours when stored at room temperature up to 86°F (30°C).
  • For patients : Refrigerate SKYTROFA cartridges at 36°F to 46°F (2°C to 8°C) in the outer carton to protect from light until the expiration date.
  • Store SKYTROFA cartridges refrigerated at 36°F to 46°F (2°C to 8°C) in the outer carton to protect from light until the expiration date.

May treat (source: NIH RxClass)

Dosage forms

Injectable

The forms currently marketed in the U.S., per the FDA National Drug Code Directory.

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Frequently asked questions

What does Skytrofa treat?
Skytrofa (Lonapegsomatropin-Tcgd) may be used to treat septo-optic dysplasia, based on NIH RxClass drug-classification data (conditions a drug may treat — not a verbatim copy of the FDA-approved label). This is general reference, not medical advice.
Is there a coupon or discount for Skytrofa?
pharmaranks is an independent ratings site, not a pharmacy — we don't issue coupons or sell Skytrofa. To pay less, ask your prescriber or pharmacist whether a generic equivalent exists, check the manufacturer's copay/savings card and patient-assistance program, and compare a pharmacy discount card against your insurance copay. Prices vary by pharmacy, insurance, and location, so always confirm at the counter. This is general reference, not medical or financial advice.
Who makes Skytrofa?
Skytrofa is marketed by Ascendis Pharma Encocrinology Div A/S. You can see Ascendis Pharma Encocrinology Div A/S's full profile, rating, and other products on pharmaranks.
Is Skytrofa a brand-name or generic drug?
Skytrofa is a brand-name product with the active ingredient Lonapegsomatropin-Tcgd.
Is Skytrofa available over the counter?
No. Skytrofa is a prescription (Rx) medication in the US — you need a prescription from a licensed clinician (in person or via telehealth); it isn't sold over the counter. For some conditions there are OTC alternatives — ask your pharmacist.
What forms does Skytrofa come in?
Skytrofa is currently marketed as injectable, per the FDA's National Drug Code Directory.
Is Skytrofa FDA-registered?
Skytrofa is on record with the U.S. FDA under application number BLA761177. You can verify this on its official FDA label.
Is Skytrofa safe?
There's no single safe-or-not verdict, and we don't yet have a composite recall-safety score for Skytrofa. Review its FDA-label side effects and warnings below, and always consult a licensed professional.
What are the side effects of Skytrofa?
Skytrofa's side effects are taken directly from its FDA label. From the label: The following important adverse reactions are described elsewhere in the labeling: Increased mortality in patients with acute critical illness [see Warnings and Precautions (5.1) ] Severe hypersensitivity [see Warnings and Precautions (5.2) ] Increased risk of neoplasms [see Warnings and Precautions… Both common and serious reactions are documented in full on this page. This is general reference from the FDA, not medical advice — always consult a professional.

Clinical content sourced from the FDA label via openFDA (U.S. FDA). View the FDA label on DailyMed → Provided for general reference only — not medical advice. Always consult a licensed professional and the current prescribing information.

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