lonapegsomatropin (Rx)

Brand and Other Names:Skytrofa, lonapegsomatropin-tcgd

Dosing & Uses

AdultPediatric

See pediatric dosing

Dosage Forms & Strengths

injection, lyophilized powder for reconstitution

  • 3mg
  • 3.6mg
  • 4.3mg
  • 5.2mg
  • 6.3mg
  • 7.6mg
  • 9.1mg
  • 11mg
  • 13.3mg
  • Available in a single-dose, dual-chamber, prefilled cartridge containing lonapegsomatropin in one chamber and water for injection (diluent) in the second chamber

Growth Hormone Deficiency

Indicated for treatment of pediatric patients aged ≥1 year who weigh ≥11.5 kg and have growth failure due to inadequate secretion of endogenous growth hormone (GH)

<1 year: Safety and efficacy not established

≥1 year and weighs ≥11.5 kg

  • Naïve patients and patients switching from daily somatropin therapy: 0.24 mg/kg IV qWeek
  • Individualize and titrate dosage based on response
  • Discontinue once epiphyseal fusion has occurred

Dosage Modifications

Renal or hepatic impairment: No specific studies have been performed

Dosing Considerations

Assess compliance; evaluate other causes of poor growth such as hypothyroidism, undernutrition, advanced bone age, and antibodies to recombinant human GH if patients experience failure to increase height velocity, particularly during the first year of treatment

Switching from somatropin therapy to lonapegsomatropin

  • Separate first dose of lonapegsomatropin and final dose of somatropin by at least 8 hr
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Interactions

Interaction Checker

and lonapegsomatropin

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                Monitor Closely (67)

                • acarbose

                  lonapegsomatropin decreases effects of acarbose by Other (see comment). Modify Therapy/Monitor Closely. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • albiglutide

                  lonapegsomatropin decreases effects of albiglutide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • alogliptin

                  lonapegsomatropin decreases effects of alogliptin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • bazedoxifene/conjugated estrogens

                  bazedoxifene/conjugated estrogens will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • betamethasone

                  lonapegsomatropin decreases effects of betamethasone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  betamethasone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • bexagliflozin

                  lonapegsomatropin decreases effects of bexagliflozin by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Growth hormone products may decrease insulin sensitivity, particularly at higher doses. Antidiabetic agents may require dose adjustment after initiating growth hormone.

                • canagliflozin

                  lonapegsomatropin decreases effects of canagliflozin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • chlorpropamide

                  lonapegsomatropin decreases effects of chlorpropamide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • conjugated estrogens

                  conjugated estrogens will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • corticotropin

                  lonapegsomatropin decreases effects of corticotropin by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  corticotropin decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • cortisone

                  lonapegsomatropin decreases effects of cortisone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  cortisone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • dapagliflozin

                  lonapegsomatropin decreases effects of dapagliflozin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • deflazacort

                  lonapegsomatropin decreases effects of deflazacort by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  deflazacort decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • dexamethasone

                  lonapegsomatropin decreases effects of dexamethasone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  dexamethasone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • dienogest/estradiol valerate

                  dienogest/estradiol valerate will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • drospirenone

                  drospirenone will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • dulaglutide

                  lonapegsomatropin decreases effects of dulaglutide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • empagliflozin

                  lonapegsomatropin decreases effects of empagliflozin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • ertugliflozin

                  lonapegsomatropin decreases effects of ertugliflozin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • estrogens conjugated synthetic

                  estrogens conjugated synthetic will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • estrogens esterified

                  estrogens esterified will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • estropipate

                  estropipate will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • ethinylestradiol

                  ethinylestradiol will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • exenatide injectable solution

                  lonapegsomatropin decreases effects of exenatide injectable solution by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • exenatide injectable suspension

                  lonapegsomatropin decreases effects of exenatide injectable suspension by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • exenatide subdermal implant

                  lonapegsomatropin decreases effects of exenatide subdermal implant by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • fludrocortisone

                  lonapegsomatropin decreases effects of fludrocortisone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  fludrocortisone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • glimepiride

                  lonapegsomatropin decreases effects of glimepiride by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • glipizide

                  lonapegsomatropin decreases effects of glipizide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • glyburide

                  lonapegsomatropin decreases effects of glyburide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • hydrocortisone

                  lonapegsomatropin decreases effects of hydrocortisone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  hydrocortisone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • insulin aspart

                  lonapegsomatropin decreases effects of insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin aspart protamine/insulin aspart

                  lonapegsomatropin decreases effects of insulin aspart protamine/insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin degludec

                  lonapegsomatropin decreases effects of insulin degludec by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin degludec/insulin aspart

                  lonapegsomatropin decreases effects of insulin degludec/insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin detemir

                  lonapegsomatropin decreases effects of insulin detemir by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin glargine

                  lonapegsomatropin decreases effects of insulin glargine by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin glulisine

                  lonapegsomatropin decreases effects of insulin glulisine by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin inhaled

                  lonapegsomatropin decreases effects of insulin inhaled by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin isophane human/insulin regular human

                  lonapegsomatropin decreases effects of insulin isophane human/insulin regular human by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin lispro

                  lonapegsomatropin decreases effects of insulin lispro by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin lispro protamine/insulin lispro

                  lonapegsomatropin decreases effects of insulin lispro protamine/insulin lispro by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin NPH

                  lonapegsomatropin decreases effects of insulin NPH by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • insulin regular human

                  lonapegsomatropin decreases effects of insulin regular human by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • linagliptin

                  lonapegsomatropin decreases effects of linagliptin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • liraglutide

                  lonapegsomatropin decreases effects of liraglutide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • lixisenatide (DSC)

                  lonapegsomatropin decreases effects of lixisenatide (DSC) by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • metformin

                  lonapegsomatropin decreases effects of metformin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • methylprednisolone

                  lonapegsomatropin decreases effects of methylprednisolone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  methylprednisolone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • miglitol

                  lonapegsomatropin decreases effects of miglitol by Other (see comment). Modify Therapy/Monitor Closely. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • mometasone sinus implant

                  lonapegsomatropin decreases effects of mometasone sinus implant by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  mometasone sinus implant decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • nateglinide

                  lonapegsomatropin decreases effects of nateglinide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • pioglitazone

                  lonapegsomatropin decreases effects of pioglitazone by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • pramlintide

                  lonapegsomatropin decreases effects of pramlintide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • prednisolone

                  lonapegsomatropin decreases effects of prednisolone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  prednisolone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • prednisone

                  lonapegsomatropin decreases effects of prednisone by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  prednisone decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • repaglinide

                  lonapegsomatropin decreases effects of repaglinide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • rosiglitazone

                  lonapegsomatropin decreases effects of rosiglitazone by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • saxagliptin

                  lonapegsomatropin decreases effects of saxagliptin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • segesterone/ethinyl estradiol

                  segesterone/ethinyl estradiol will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages.

                • semaglutide

                  lonapegsomatropin decreases effects of semaglutide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • sitagliptin

                  lonapegsomatropin decreases effects of sitagliptin by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • tirzepatide

                  lonapegsomatropin decreases effects of tirzepatide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • tolazamide

                  lonapegsomatropin decreases effects of tolazamide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • tolbutamide

                  lonapegsomatropin decreases effects of tolbutamide by Other (see comment). Use Caution/Monitor. Comment: Closely monitor blood glucose when treated with antidiabetic agents. Lonapegsomatropin 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.

                • triamcinolone acetonide extended-release injectable suspension

                  lonapegsomatropin decreases effects of triamcinolone acetonide extended-release injectable suspension by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  triamcinolone acetonide extended-release injectable suspension decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                • triamcinolone acetonide injectable suspension

                  lonapegsomatropin decreases effects of triamcinolone acetonide injectable suspension by Other (see comment). Use Caution/Monitor. Comment: Growth hormone (GH) inhibits microsomal enzyme 11 beta-hydroxysteroid dehydrogenase type 1, which converts cortisone to its active metabolite, cortisol. Patients with untreated GH deficiency may have increases in serum cortisol, and initiation of lonapegsomatropin may result decreased serum cortisol. Patients with hypoadrenalism treated with glucocorticoids may require an increase glucocorticoid stress or maintenance doses following lonapegsomatropin initiation.

                  triamcinolone acetonide injectable suspension decreases effects of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Comment: Glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth promoting effects of lonapegsomatropin in children. Carefully adjust glucocorticoid replacement dosing in children receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth.

                Minor (0)

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                  Adverse Effects

                  >10%

                  Elevated phosphate levels (44.2%)

                  Elevated alkaline phosphatase levels (19.2%)

                  Viral infection (15%)

                  Pyrexia (15%)

                  Cough (11%)

                  Nausea and vomiting (11%)

                  1-10%

                  Hemorrhage (7%)

                  Diarrhea (6%)

                  Abdominal pain (6%)

                  Arthralgia and arthritis (6%)

                  Postmarketing Reports

                  Severe systemic hypersensitivity reactions including anaphylactic reactions and angioedema

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                  Warnings

                  Contraindications

                  Acute critical illness after open heart surgery, abdominal surgery, multiple accidental traumas, or those with acute respiratory failure

                  Hypersensitivity to somatropin or any of the excipients

                  Closed epiphyses

                  Active malignancy, owing to risk of malignancy progression

                  Active proliferative or severe nonproliferative diabetic retinopathy

                  Prader-Willi syndrome who are severely obese, have a history of upper airway obstruction or sleep apnea, or have severe respiratory impairment

                  Cautions

                  Increased mortality reported among patients with acute critical illness, owing to complications following open heart surgery, abdominal surgery, multiple accidental traumas, or those with acute respiratory failure; safety of continuing treatment in such patients receiving replacement doses has not been established

                  Serious systemic hypersensitivity reactions (eg, anaphylactic reactions, angioedema) reported; inform patients and caregivers that such reactions are possible and to seek immediate medical attention if allergic reaction occurs

                  May decrease insulin sensitivity, particularly at higher doses; previously undiagnosed impaired glucose tolerance and overt type 2 diabetes mellitus (DM) may be unmasked; closely monitor glucose levels when initiating and during treatment in patients with preexisting type 1 or type 2 DM or impaired glucose tolerance; adjust doses of antihyperglycemic drugs as needed

                  Fluid retention may occur; clinical manifestations of fluid retention (eg, edema, arthralgia, myalgia, nerve compression syndromes including carpal tunnel syndrome/paresthesia) are usually transient and dose-dependent

                  Undiagnosed or untreated hypothyroidism may prevent optimal treatment response; perform periodic thyroid function tests and initiate or appropriately adjust thyroid hormone replacement therapy when indicated

                  Reports of fatalities after initiating therapy with somatropin documented in pediatric patients with Prader-Willi syndrome who had ≥1 of the following risk factors: severe obesity, history of upper airway obstruction or sleep apnea, or unidentified respiratory infection; male patients with ≥1 factors may be at greater risk than females

                  Not indicated for treatment of pediatric patients who have growth failure due to genetically confirmed Prader-Willi syndrome

                  Slipped capital femoral epiphysis may occur more frequently in patients undergoing rapid growth; evaluate patients with the onset of a limp or complaints of hip or knee pain

                  Pancreatitis reported; consider pancreatitis in patients who develop persistent severe abdominal pain

                  When somatropin is administered SC at same site over a long period, tissue atrophy may result; avoid by rotating injection site

                  Treated patients 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; patients treated with glucocorticoid replacement for previously diagnosed hypoadrenalism may require an increase in their maintenance or stress dose following initiation of treatment; monitor for reduced serum cortisol levels and/or need for glucocorticoid dose increases in those with known hypoadrenalism

                  Serum levels of phosphate, alkaline phosphatase, and parathyroid hormone may increase after treatment; monitor these laboratory tests if abnormal

                  Somatropin increases growth rate, and progression of existing scoliosis can occur in patients who experience rapid growth; somatropin has not been shown to increase occurrence of scoliosis; monitor patients with a history of scoliosis for disease progression

                  Increased risk of neoplasms

                  • Somatropin treatment may increase risk of malignancy progression in patients with active malignancy
                  • Any preexisting malignancy should be inactive and its treatment complete before initiating somatotropin; discontinue therapy if there is evidence of recurrent activity
                  • An increased risk of second neoplasm reported in childhood cancer survivors treated with somatropin; the most common second neoplasms were intracranial tumors (eg, meningiomas) in patients treated with radiation to the head for their first neoplasm
                  • Monitor all patients with a history of GH deficiency secondary to an intracranial neoplasm while on somatropin therapy for progression or recurrence of the tumor
                  • Because pediatric patients with certain rare genetic causes of short stature have an increased risk of developing malignancies, thoroughly consider the risks and benefits of starting treatment in these patients; monitor for development of neoplasms if initiating treatment
                  • Monitor 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

                  Intracranial hypertension

                  • Intracranial hypertension (IH) with papilledema, visual changes, headache, nausea, and/or vomiting reported
                  • In reported cases, IH-associated signs and symptoms rapidly resolved after discontinuing therapy or reducing the dose
                  • Perform funduscopic examination routinely before initiating treatment to exclude preexisting papilledema, and periodically thereafter
                  • If papilledema observed by fundoscopy, stop somatropin treatment
                  • If somatropin-induced IH is confirmed, restart treatment at a lower dose once IH-associated signs and symptoms resolve

                  Drug interaction overview

                  • Replacement glucocorticoid treatment
                    • Patients treated with glucocorticoid replacement for hypoadrenalism may require an increase in their maintenance or stress dose following initiation
                    • 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
                    • Initiating lonapegsomatropin may result in inhibition of 11βHSD-1 and reduced serum cortisol concentrations
                  • Pharmacologic glucocorticoid therapy and supraphysiologic glucocorticoid treatment
                    • Carefully adjust glucocorticoid replacement dosing in pediatric patients receiving glucocorticoid treatments to avoid both hypoadrenalism and an inhibitory effect on growth
                    • Pharmacologic glucocorticoid therapy and supraphysiologic glucocorticoid treatment may potentiate the growth-promoting effects of lonapegsomatropin in pediatric patients
                  • Cytochrome P450-metabolizing drugs
                    • Carefully monitor when used in combination with drugs metabolized by cytochrome P450 (CYP450) liver enzymes
                    • Limited published data indicate that somatropin treatment increases CYP450-mediated antipyrine clearance
                    • Lonapegsomatropin may alter clearance of compounds known to be metabolized by CYP450 liver enzymes
                  • Oral estrogen
                    • Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages
                    • Oral estrogens may reduce the serum insulinlike growth factor-1 response to lonapegsomatropin
                  • Insulin and/or other antihyperglycemic agents
                    • Patients with diabetes mellitus may require dosage adjustment of their insulin and/or other antihyperglycemic agents
                    • Lonapegsomatropin may decrease insulin sensitivity, particularly at higher doses
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                  Pregnancy & Lactation

                  Pregnancy

                  There are no available data on use in pregnant females to evaluate a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes

                  Available published data over several decades for somatropin, the active component of lonapegsomatropin, have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes

                  Lactation

                  No data are available on presence of lonapegsomatropin in human milk, effects on the breastfed infant, or effects on milk production

                  High-molecular–weight therapeutic proteins, including lonapegsomatropin, are expected to have low passage into human milk and limited systemic exposure in breastfed infants

                  No adverse effects on breastfed infants have been reported with somatropin

                  Pregnancy Categories

                  A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

                  B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

                  C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

                  D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

                  X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

                  NA: Information not available.

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                  Pharmacology

                  Mechanism of Action

                  Long-acting prodrug of somatropin (recombinant human GH)

                  Somatropin binds to GH receptor on target cells, resulting intracellular signal transduction and a host of pharmacodynamic effects

                  Somatropin stimulates skeletal growth in pediatric patients with GH deficiency as a result of effects on epiphyses of long bones

                  Absorption

                  AUC: 500 h⋅ng/mL

                  Peak plasma concentration

                  • Lonapegsomatropin: 1230 ng hGH/mL
                  • Somatotropin: 15.2 ng/mL
                  • Methoxypolyethylene glycol carrier: 13.1 mcg/L

                  Peak plasma time

                  • Lonapegsomatropin: 25 hr
                  • Somatropin: 12 hr
                  • Methoxypolyethylene glycol carrier: 36 hr

                  Distribution

                  Vd: 0.13 L/kg

                  Metabolism

                  Metabolism of somatropin involves protein catabolism in both the liver and kidneys

                  Methoxypolyethylene glycol carrier is cleared by the kidneys

                  Elimination

                  Clearance: 3.2 mL/h/kg

                  Half-life

                  • Lonapegsomatropin: 30.7 hr
                  • Somatropin: 25 hr
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                  Administration

                  SC Preparation

                  Selection of appropriate cartridge is based on prescribed dose (mg/kg) and patient’s body weight (kg)

                  For a prescribed dose of 0.24 mg/kg/week and patient’s weight is 11.5-100 kg, follow the recommended dosing

                  • 11.5-13.9 kg: 3 mg/week
                  • 14-16.4 kg: 3.6 mg/week
                  • 16.5-19.9 kg: 4.3 mg/week
                  • 20-23.9 kg: 5.2 mg/week
                  • 24-28.9 kg: 6.3 mg/week
                  • 29-34.9 kg: 7.6 mg/week
                  • 35- 41.9 kg: 9.1 mg/week
                  • 42-50.9 kg: 11 mg/week
                  • 51-60.4 kg: 13.3 mg/week
                  • 60.5-69.9 kg: 15.2 mg/week (use 2 cartridges of 7.6 mg each)
                  • 70- 84.9 kg: 18.2 mg/week (use 2 cartridges of 9.1 mg each)
                  • 85-100 kg: 22 mg/week (use 2 cartridges of 11 mg each)

                  For a prescribed dose other than 0.24 mg/kg/week, calculate total weekly dose (in mg) and select appropriate cartridge as follows:

                  Total weekly dose (mg) = Prescribed weekly dose (mg/kg) x patient’s body weight (kg)

                  Round total weekly dose (mg) to closest cartridge dose while also considering treatment goals and clinical response

                  Cartridge has been designed for use only with autoinjector

                  If refrigerated, calibrate cartridge to room temperature for 15 minutes before use

                  Autoinjector provides a fully automated reconstitution of the lyophilized drug product, which is followed by a manual mixing step controlled by the device

                  Insert injection needle into skin; the device automatically delivers the drug

                  Built-in electronics and software assist the user during drug preparation and administration, and confirm dose delivery

                  SC Administration

                  Administer SC into abdomen, buttock, or thighs; rotate injection sites between and within regions to reduce the risk of lipoatrophy

                  Refer to Instructions for Use [www.Skytrofa.com/IFU] for complete administration instructions with illustrations

                  Diluted solution appears clear and colorless to opalescent and may occasionally contain air bubbles; do NOT inject if solution is cloudy or contains particulate matter

                  Use cartridges within 4 hr after reconstitution; discard reconstituted cartridges after 4 hours when stored at room temperature up to 86ºF (30ºC)

                  Missed doses

                  • ≤2 days
                    • Administer as soon as possible
                    • Take 2 days before or after scheduled dosing day
                    • Resume once-weekly dosing for the next dose at previously scheduled dosing day
                  • >2 days
                    • Skip dose and administer the next dose on the regularly scheduled day
                    • At least 5 days should elapse between doses

                  Storage

                  Unopened cartridges

                  • For patients
                    • Store in outer carton to protect from light until expiration date
                    • May refrigerate at 2-8ºC (36-46ºF); do not freeze
                    • Alternatively, store at room temperature (up to 30ºC [86ºF]) for up to 6 months; may return to refrigeration within the 6 months
                    • Write date first removed from refrigerator on outer carton
                    • Do not use beyond the expiration date or 6 months after the date it was first removed from refrigeration (whichever is earlier)
                  • For pharmacy long-term storage
                    • Refrigerate at 2-8ºC (36-46ºF) in outer carton until expiration date; do not freeze

                  Reconstituted cartridges

                  • Store at room temperature up to 30ºC (86ºF); discard 4 hr after reconstitution
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                  Images

                  No images available for this drug.
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                  Patient Handout

                  A Patient Handout is not currently available for this monograph.
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                  Formulary

                  FormularyPatient Discounts

                  Adding plans allows you to compare formulary status to other drugs in the same class.

                  To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

                  Adding plans allows you to:

                  • View the formulary and any restrictions for each plan.
                  • Manage and view all your plans together – even plans in different states.
                  • Compare formulary status to other drugs in the same class.
                  • Access your plan list on any device – mobile or desktop.

                  The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

                  Tier Description
                  1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
                  2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
                  3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
                  4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
                  5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
                  6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
                  NC NOT COVERED – Drugs that are not covered by the plan.
                  Code Definition
                  PA Prior Authorization
                  Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
                  QL Quantity Limits
                  Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
                  ST Step Therapy
                  Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
                  OR Other Restrictions
                  Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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                  Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.