Most Serious and/or Most Frequently Observed Adverse Reactions

This list presents the most serious^b and/or most frequently observed^a adverse reactions during treatment with somatropin:

• ^b Sudden death in pediatric patients with Prader-Willi syndrome with risk factors including severe obesity, history of upper airway obstruction or sleep apnea and unidentified respiratory infection [see CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS]
• ^b Intracranial tumors, in particular meningiomas, in teenagers/young adults treated with radiation to the head as children for a first neoplasm and somatropin [see CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS]
• ^{a, b} Glucose intolerance including impaired glucose tolerance/impaired fasting glucose as well as overt diabetes mellitus [see WARNINGS AND PRECAUTIONS]
• ^b Intracranial hypertension [see WARNINGS AND PRECAUTIONS]
• ^b Significant diabetic retinopathy [see CONTRAINDICATIONS]
• ^b Slipped capital femoral epiphysis in pediatric patients [see WARNINGS AND PRECAUTIONS]
• ^b Progression of preexisting scoliosis in pediatric patients [see WARNINGS AND PRECAUTIONS]
• ^a Fluid retention manifested by edema, arthralgia, myalgia, nerve compression syndromes including carpal tunnel syndrome/paraesthesias [see WARNINGS AND PRECAUTIONS]
• ^a Unmasking of latent central hypothyroidism [see WARNINGS AND PRECAUTIONS]
• ^a Injection site reactions/rashes and lipoatrophy (as well as rare generalized hypersensitivity reactions) [see WARNINGS AND PRECAUTIONS]

Clinical Trials Experience

Because clinical trials are conducted under varying conditions, adverse reaction rates observed during the clinical trials performed with one somatropin formulation cannot always be directly compared to the rates observed during the clinical trials performed with a second somatropin formulation, and may not reflect the adverse reaction rates observed in practice.

Clinical Trials in children with GHD

In clinical studies with GENOTROPIN (somatropin [rdna origin]) in pediatric GHD patients, the following events were reported infrequently: injection site reactions, including pain or burning associated with the injection, fibrosis, nodules, rash, inflammation, pigmentation, or bleeding; lipoatrophy; headache; hematuria; hypothyroidism; and mild hyperglycemia.

Clinical Trials in PWS

In two clinical studies with GENOTROPIN (somatropin [rdna origin]) in pediatric patients with Prader-Willi syndrome, the following drug-related events were reported: edema, aggressiveness, arthralgia, benign intracranial hypertension, hair loss, headache, and myalgia.

Clinical Trials in children with SGA

In clinical studies of 273 pediatric patients born small for gestational age treated with GENOTROPIN (somatropin [rdna origin]) , the following clinically significant events were reported: mild transient hyperglycemia, one patient with benign intracranial hypertension, two patients with central precocious puberty, two patients with jaw prominence, and several patients with aggravation of preexisting scoliosis, injection site reactions, and self-limited progression of pigmented nevi. Anti-hGH antibodies were not detected in any of the patients treated with GENOTROPIN (somatropin [rdna origin]) .

Clinical Trials in children with Turner Syndrome

In two clinical studies with GENOTROPIN (somatropin [rdna origin]) in pediatric patients with Turner syndrome, the most frequently reported adverse events were respiratory illnesses (influenza, tonsillitis, otitis, sinusitis), joint pain, and urinary tract infection. The only treatment-related adverse event that occurred in more than 1 patient was joint pain.

Clinical Trials in children with Idiopathic Short Stature

In two open-label clinical studies with GENOTROPIN (somatropin [rdna origin]) in pediatric patients with ISS, the most commonly encountered adverse events include upper respiratory tract infections, influenza, tonsillitis, nasopharyngitis, gastroenteritis, headaches, increased appetite, pyrexia, fracture, altered mood, and arthralgia. In one of the two studies, during Genotropin (somatropin [rdna origin]) treatment, the mean IGF-1 standard deviation (SD) scores were maintained in the normal range. IGF-1 SD scores above +2 SD were observed as follows: 1 subject (3%), 10 subjects (30%) and 16 subjects (38%) in the untreated control, 0. 23 and the 0.47 mg/kg/week groups, respectively, had at least one measurement; while 0 subjects (0%), 2 subjects (7%) and 6 subjects (14%) had two or more consecutive IGF-1 measurements above +2 SD.

Clinical Trials in adults with GHD

In clinical trials with GENOTROPIN (somatropin [rdna origin]) in 1,145 GHD adults, the majority of the adverse events consisted of mild to moderate symptoms of fluid retention, including peripheral swelling, arthralgia, pain and stiffness of the extremities, peripheral edema, myalgia, paresthesia, and hypoesthesia. These events were reported early during therapy, and tended to be transient and/or responsive to dosage reduction.

Table 1 displays the adverse events reported by 5% or more of adult GHD patients in clinical trials after various durations of treatment with GENOTROPIN (somatropin [rdna origin]) . Also presented are the corresponding incidence rates of these adverse events in placebo patients during the 6-month double-blind portion of the clinical trials.

Table 1: Adverse Events Reported by ≥ 5% of 1,145 Adult GHD Patients During Clinical Trials of GENOTROPIN (somatropin [rdna origin]) and Placebo, Grouped by Duration of Treatment

Post-Trial Extension Studies in Adults

In expanded post-trial extension studies, diabetes mellitus developed in 12 of 3,031 patients (0.4%) during treatment with GENOTROPIN (somatropin [rdna origin]) . All 12 patients had predisposing factors, e.g., elevated glycated hemoglobin levels and/or marked obesity, prior to receiving GENOTROPIN (somatropin [rdna origin]) . Of the 3,031 patients receiving GENOTROPIN (somatropin [rdna origin]) , 61 (2%) developed symptoms of carpal tunnel syndrome, which lessened after dosage reduction or treatment interruption (52) or surgery (9). Other adverse events that have been reported include generalized edema and hypoesthesia.

Anti-hGH Antibodies

As with all protein drugs, a small percentage of patients may develop antibodies to the protein. GH antibodies with binding capacities lower than 2 mg/L have not been associated with growth attenuation. In a very small number of patients, when binding capacity was greater than 2 mg/L, interference with the growth response was observed.

In 419 pediatric patients evaluated in clinical studies with GENOTROPIN (somatropin [rdna origin]) lyophilized powder, 244 had been treated previously with GENOTROPIN (somatropin [rdna origin]) or other growth hormone preparations and 175 had received no previous growth hormone therapy. Antibodies to growth hormone (anti-hGH antibodies) were present in six previously treated patients at baseline. Three of the six became negative for anti-hGH antibodies during 6 to 12 months of treatment with GENOTROPIN (somatropin [rdna origin]) . Of the remaining 413 patients, eight (1.9%) developed detectable anti-hGH antibodies during treatment with GENOTROPIN (somatropin [rdna origin]) ; none had an antibody binding capacity > 2 mg/L. There was no evidence that the growth response to GENOTROPIN (somatropin [rdna origin]) was affected in these antibody-positive patients.

Periplasmic Escherichia coli Peptides

Preparations of GENOTROPIN (somatropin [rdna origin]) contain a small amount of periplasmic Escherichia coli peptides (PECP). Anti-PECP antibodies are found in a small number of patients treated with GENOTROPIN (somatropin [rdna origin]) , but these appear to be of no clinical significance.

Post-Marketing Surveillance

Because these adverse events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The adverse events reported during post-marketing surveillance do not differ from those listed/discussed above in Sections 6.1 and 6.2 in children and adults.

Leukemia has been reported in a small number of GH deficient children treated with somatropin, somatrem (methionylated rhGH) and GH of pituitary origin. It is uncertain whether these cases of leukemia are related to GH therapy, the pathology of GHD itself, or other associated treatments such as radiation therapy. On the basis of current evidence, experts have not been able to conclude that GH therapy per se was responsible for these cases of leukemia. The risk for children with GHD, if any, remains to be established [see CONTRAINDICATIONS and WARNINGS AND PRECAUTIONS].

The following additional adverse reactions have been observed during the appropriate use of somatropin: headaches (children and adults),rare gynecomastia (children), and rare pancreatitis (children).

Read the Genotropin (somatropin [rdna origin]) Side Effects Center for a complete guide to possible side effects »

Inhibition of 11β-Hydroxysteroid Dehydrogenase Type 1 (11βHSD-1)

Somatropin inhibits 11β-hydroxysteroid dehydrogenase type 1 (11βHSD-1) in adipose/hepatic tissue and may significantly impact the metabolism of cortisol and cortisone. As a consequence, in patients treated with somatropin, previously undiagnosed central (secondary) hypoadrenalism may be unmasked requiring glucocorticoid replacement therapy. In addition, patients treated with glucocorticoid replacement therapy for previously diagnosed hypoadrenalism may require an increase in their maintenance or stress doses; this may be especially true for patients treated with cortisone acetate and prednisone since conversion of these drugs to their biologically active metabolites is dependent on the activity of the 11βHSD-1 enzyme.

Glucocorticoid Replacement

Excessive glucocorticoid therapy may attenuate the growth promoting effects of somatropin in children. Therefore, glucocorticoid replacement therapy should be carefully adjusted in children with concomitant GH and glucocorticoid deficiency to avoid both hypoadrenalism and an inhibitory effect on growth.

Cytochrome P450-Metabolized Drugs

Limited published data indicate that somatropin treatment increases cytochrome P450 (CYP450)-mediated antipyrine clearance in man. These data suggest that somatropin administration may alter the clearance of compounds known to be metabolized by CYP450 liver enzymes (e.g., corticosteroids, sex steroids, anticonvulsants, cyclosporine). Careful monitoring is advisable when somatropin is administered in combination with other drugs known to be metabolized by CYP450 liver enzymes. However, formal drug interaction studies have not been conducted.

Oral Estrogen

In patients on oral estrogen replacement, a larger dose of somatropin may be required to achieve the defined treatment goal [see DOSAGE AND ADMINISTRATION].

Insulin and/or Oral Hypoglycemic Agents

In patients with diabetes mellitus requiring drug therapy, the dose of insulin and/or oral agent may require adjustment when somatropin therapy is initiated [see WARNINGS AND PRECAUTIONS).

Last reviewed on RxList: 6/16/2009
This monograph has been modified to include the generic and brand name in many instances.