Somatrogon

Somatrogon is a prescription medication used for pediatric patients aged 3 years and above who have growth failure owing to inadequate secretion of endogenous growth hormone.

• Somatrogon is available under the following different brand names: Ngenla

Common side effects of Somatrogon include:

• injection site reactions (pain, swelling, redness, itching, bleeding)
• runny or stuffy nose
• headache 
• fever
• anemia 
• cough
• vomiting
• hypothyroidism 
• abdominal pain 
• rash
• sore throat
• Serious side effects of Somatrogon include:
• fluid retention
• glucose intolerance and diabetes mellitus
• hypoadrenalism
• hypothyroidism
• increased mortality in patients with acute critical illness
• increased risk of neoplasm
• intracranial hypertension
• progression of preexisting scoliosis
• severe hypersensitivity
• sudden death in pediatric patients with prader-willi syndrome

Rare side effects of Somatrogon include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, coordination loss, unsteady, very stiff muscles, high fever, profuse sweating, or tremors
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, light-headedness, or passing out

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Pediatric dosage

Injection, solution

• 24 mg/1.2 mL (20 mg/mL) prefilled pen; delivers dose in 0.2-mg increments
• 60 mg/1.2 mL (50 mg/mL) prefilled pen; delivers dose in 0.5-mg increments

Growth hormone deficiency

Pediatric dosage

• 0.66 mg/kg (actual body weight) SC every week
• Individualize dosage for each patient based on growth response

Dosage Considerations – Should be Given as Follows:

• See "Dosages"

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, healthcare provider, or pharmacist first.

• Somatrogon has severe interactions with no other drugs.
• Somatrogon has serious interactions with no other drugs.
• Somatrogon has moderate interactions with at least 39 other drugs.
• Somatrogon has minor interactions with no other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, health questions, or concerns.

Contraindications

• Acute critical illness after open heart surgery, abdominal surgery, or multiple accidental trauma or those with acute respiratory failure owing to the risk for increased mortality with somatropin
• Hypersensitivity to somatrogon or excipients
• Closed epiphyses
• Active malignancy owing to the risk for malignancy progression
• Active proliferative or severe nonproliferative diabetic retinopathy
• Prader-Willi syndrome in patients who are severely obese, have a history of upper airway obstruction or sleep apnea, or have severe respiratory impairment owing to the risk for sudden death

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Somatrogon?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Somatrogon?”

Cautions

• Fluid retention may occur, including clinical manifestations (eg, edema, nerve compression syndromes including carpal tunnel syndrome/paresthesia) are usually transient and dose-dependent
• Slipped capital femoral epiphysis may occur more frequently in patients undergoing rapid growth; evaluate patients with onset of a limp or complaints of persistent hip or knee pain
• Somatrogon increases growth rate, and progression of preexisting scoliosis can occur in patients who experience rapid growth; growth hormone treatment has not been shown to increase the occurrence of scoliosis; monitor patients with a history of scoliosis for disease progression
• Pancreatitis reported; risk may be greater in pediatric patients than in adults; consider pancreatitis in patients who develop persistent severe abdominal pain
• Lipoatrophy may occur when administered SC at the same site over a long period; rotate injection sites to reduce risk
• Serum levels of phosphorus, alkaline phosphatase, and parathyroid hormone may increase; monitor as appropriate
• Increased mortality with acute critical illness
• Increased mortality in patients with acute critical illness owing to complications following open heart surgery, abdominal surgery, or multiple accidental trauma or those with acute respiratory failure has been reported
• Safety of continuing treatment in patients who concurrently develop these illnesses has not been established
• Hypersensitivity
  • Severe hypersensitivity reactions, including anaphylaxis and angioedema, reported
  • Inform patients and/or caregivers about the possibility of hypersensitivity and to seek prompt medical attention if an allergic reaction occurs
• Risk for neoplasms
• Active malignancy
  • Increased risk for malignancy progression
  • Any preexisting malignancy should be inactive, and its treatment completed before initiating therapy
  • Discontinue somatrogon with evidence of recurrent malignancy
• Risk for a second neoplasm
  • Increased risk for second neoplasm reported in childhood cancer survivors treated with radiation to the brain/head for their first neoplasm and who developed subsequent growth hormone deficiency (GHD) and were treated with somatropin
  • Intracranial tumors, meningiomas, were the most common of these second neoplasms
  • Monitor for progression or recurrence of the tumor in all patients who have a history of GHD secondary to an intracranial neoplasm while on somatrogon
• New malignancy during treatment
  • Consider risks and benefits in children with certain rare genetic causes of short stature because these children have an increased risk of developing malignancies
  • If treatment is initiated, carefully monitor for the development of neoplasms
  • Monitor for increased growth or potential malignant changes of preexisting nevi
  • Advise patients and/or caregivers to report marked changes in behavior, the onset of headaches, vision disturbances, and/or changes in skin pigmentation or changes in the appearance of preexisting nevi
• Glucose intolerance and diabetes mellitus
  • Growth hormone treatment may decrease insulin sensitivity, particularly at higher doses
  • New-onset type 2 diabetes reported in patients receiving growth hormone
  • Patients with undiagnosed prediabetes and diabetes mellitus may experience worsened glycemic control and become symptomatic
  • Monitor glucose levels periodically in all patients, especially those with risk factors for diabetes mellitus (eg, obesity, Turner syndrome, family history of diabetes mellitus)
  • Monitor patients with preexisting type 1 or type 2 diabetes or prediabetes closely
  • Doses of antidiabetic agents may require adjustment when initiating somatrogon
• Intracranial hypertension (IH)
  • IH within 8 weeks after initiating
  • In all reported cases, IH-associated signs and symptoms rapidly resolved after cessation of therapy or a reduction of the somatropin dose
  • Perform fundoscopic examination before initiating treatment to exclude preexisting papilledema and periodically thereafter
  • If papilledema is identified before initiating, evaluate the etiology and treat the underlying cause before initiating
  • Temporarily discontinue in patients with clinical or fundoscopic evidence of IH
  • If IH is confirmed, restart treatment at a lower dose after IH-associated signs and symptoms have resolved
• Hypoadrenalism
  • Patients who have or are at a risk for pituitary hormone deficiency(s) may be at a risk for reduced serum cortisol levels and/or unmasking of central (secondary) hypoadrenalism
  • Patients treated with glucocorticoid replacement for previously diagnosed hypoadrenalism may require an increase in their maintenance or stress doses following the initiation of somatrogon treatment
  • Monitor for reduced serum cortisol levels and/or need for glucocorticoid dose increases in those with known hypoadrenalism
• Hypothyroidism
  • Undiagnosed/untreated hypothyroidism may prevent an optimal response to somatrogon
  • In patients with GHD, central (secondary) hypothyroidism may first become evident or worsen during treatment with growth hormone therapy
  • Initiate periodic thyroid function tests and thyroid hormone replacement therapy or appropriately adjust treatment when indicated
• Sudden death in patients with Prader-Willi syndrome
  • Sudden death reported after initiating therapy in pediatric patients with Prader-Willi syndrome who had more than one of the following risk factors: severe obesity, history of upper airway obstruction or sleep apnea, or unidentified respiratory infection
  • Men may be at greater risk than women
  • Not indicated for the treatment of pediatric patients who have growth failure owing to genetically confirmed Prader-Willi syndrome
• Drug interaction overview
• Replacement glucocorticoid treatment
  • Dosage modification/monitor of glucocorticoid
  • Microsomal enzyme 11-beta-hydroxysteroid dehydrogenase type 1 (11-beta HSD-1) is required for the conversion of cortisone to its active metabolite, cortisol, in hepatic and adipose tissue
  • Growth hormone inhibits 11-beta HSD-1; consequently, individuals with untreated GHD have relative increases in 11-beta HSD-1 and serum cortisol
  • Initiation of somatrogon may inhibit 11-beta HSD-1 and reduce serum cortisol concentrations
  • Patients treated with glucocorticoid replacement for hypoadrenalism may require increased maintenance or stress doses after initiating somatrogon
  • Cortisone acetate and prednisone may be affected more than others because the conversion of these drugs to their biologically active metabolites depends on 11-beta HSD-1
• Supraphysiologic glucocorticoid treatment
  • Dosage modification/monitor of glucocorticoid
  • Supraphysiologic glucocorticoid treatment may attenuate the growth-promoting effects of somatrogon
  • Carefully adjust glucocorticoid replacement dosing in patients receiving glucocorticoid treatments to avoid hypoadrenalism and an inhibitory effect on growth
• CYP450 substrates
  • Monitor
  • Limited data indicate growth hormone treatment increases cytochrome P450 (CYP450)-mediated antipyrine clearance
  • Somatrogon may alter the clearance of compounds known to be metabolized by CYP450 liver enzymes
• Oral estrogen
  • Modify the dose of somatrogon
  • Oral estrogens may reduce serum insulin-like growth factor 1 response to somatrogon
  • Patients receiving oral estrogen replacement may require higher somatrogon dosages
• Insulin/antihyperglycemic agents
  • Modify dose/monitor
  • Treatment with somatrogon may decrease insulin sensitivity, particularly at higher doses
  • Patients with diabetes mellitus may require adjustment of their doses of insulin and/or other antihyperglycemic agents

Pregnancy and Lactation

• Data are unavailable on use in pregnant women to evaluate for a drug-associated risk for major birth defects, miscarriage, or other adverse maternal or fetal outcomes
• Pregnancy testing
  • Although somatrogon did not interfere with human chorionic gonadotropin (hCG) pregnancy testing in a limited number of commercial tests, interference with hCG blood and urine pregnancy testing in patients receiving somatrogon may be possible, leading to either false-positive or false-negative results
  • Alternative methods (ie, not reliant on hCG) are recommended to determine pregnancy
• Lactation
  • Data are unavailable on the presence of somatrogon in human or animal milk, its effects on breastfed infants, or its effects on milk production