Serostim (Somatropin) - Drug Interactions, Contraindications, Overdosage, etc

DRUG INTERACTIONS

Drug Interactions

Formal drug interaction studies have not been conducted. No data are available on drug interactions between Serostim^® and HIV protease inhibitors or the non-nucleoside reverse transcriptase inhibitors.

Published in vitro data indicate that growth hormone may be an inducer of cytochrome P450 3A4. In clinical trials of HIV-infected patients with wasting or HARS who were receiving antiretroviral therapy, Serostim^® did not adversely alter antiretroviral effectiveness, such as mean circulating levels of CD4 counts or HIV-1 RNA (viral load). When Serostim^® is administered in combination with drugs known to be metabolized by CYP P450 3A4 hepatic enzymes, such as some antiretroviral drugs, it is advisable to monitor the clinical effectiveness of these drugs.

Somatropin inhibits 11beta-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 primary (and 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.

OVERDOSAGE

Glucose intolerance can occur with overdosage. Long-term overdosage with growth hormone could result in signs and symptoms of acromegaly.

CONTRAINDICATIONS

Growth hormone therapy should not be initiated in patients with acute critical illness due to complications following open heart or abdominal surgery, multiple accidental trauma or acute respiratory failure. Two placebo-controlled clinical trials in non-growth hormone deficient adult patients (n=522) with these conditions revealed a significant increase in mortality (41.9% vs. 19.3%) among somatropin-treated patients (doses 5.3-8 mg/day) compared to those receiving placebo (see WARNINGS).

Serostim^® is contraindicated in patients with active neoplasia (either newly diagnosed or recurrent).  Any anti-tumor therapy should be completed prior to starting therapy with Serostim^®.

Serostim^® [somatropin (rDNA origin) for injection] reconstituted with Bacteriostatic Water for Injection, USP (0.9% Benzyl Alcohol) should not be administered to patients with a known sensitivity to Benzyl Alcohol.  (see WARNINGS).

Serostim^® is contraindicated in patients with a known hypersensitivity to growth hormone.