Overview
DESCRIPTION Mitomycin (also known as mitomycin and/or mitomycin-C) is an antibiotic isolated from the broth of Streptomyces caespitosus which has been shown to have antitumor activity. The compound is heat stable, has a high melting point, and is freely soluble in organic solvents.
Mechanism of Action
CLINICAL PHARMACOLOGY Mitomycin selectively inhibits the synthesis of deoxyribonucleic acid (DNA). The guanine and cytosine content correlates with the degree of mitomycin-induced cross-linking. At high concentrations of the drug, cellular RNA and protein synthesis are also suppressed. In humans, mitomycin is rapidly cleared from the serum after intravenous administration. Time required to reduce the serum concentration by 50% after a 30 mg bolus injection is 17 minutes. After injection of 30 mg, 20 mg, or 10 mg I.V., the maximal serum concentrations were 2.4 mcg/mL, 1.7 mcg/mL, and 0.52 mcg/mL, respectively. Clearance is effected primarily by metabolism in the liver, but metabolism occurs in other tissues as well.
Indications
- INDICATIONS AND USAGE Mitomycin for Injection is not recommended as single-agent, primary therapy. It has been shown to be useful in the therapy of disseminated adenocarcinoma of the stomach or pancreas in proven combinations with other approved chemotherapeutic agents and as palliative treatment when other modalities have failed. Mitomycin is not recommended to replace appropriate surgery and/or radiotherapy.
Common Doses
- 40 mg
- 80 mg
- 80 mL
- 20 mg
Dosage
DOSAGE AND ADMINISTRATION Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. Mitomycin should be given intravenously only, using care to avoid extravasation of the compound. If extravasation occurs, cellulitis, ulceration, and slough may result. Each Single-Dose vial contains mitomycin 40 mg and mannitol 80 mg. To administer, add Sterile Water for Injection, 80 mL. Shake to dissolve. If product does not dissolve immediately, allow to stand at room temperature until solution is obtained.
Black Box Warning
WARNING Mitomycin should be administered under the supervision of a qualified physician experienced in the use of cancer chemotherapeutic agents. Appropriate management of therapy and complications is possible only when adequate diagnostic and treatment facilities are readily available. Bone marrow suppression, notably thrombocytopenia and leukopenia, which may contribute to overwhelming infections in an already compromised patient, is the most common and severe of the toxic effects of mitomycin (see WARNINGS and ADVERSE REACTIONS sections).
Contraindications
- CONTRAINDICATIONS Mitomycin is contraindicated in patients who have demonstrated a hypersensitive or idiosyncratic reaction to it in the past. Mitomycin is contraindicated in patients with thrombocytopenia, coagulation disorder, or an increase in bleeding tendency due to other causes.
Side Effects
- ADVERSE REACTIONS Bone Marrow Toxicity This was the most common and most serious toxicity, occurring in 605 of 937 patients (64.4%). Thrombocytopenia and/or leukopenia may occur anytime within 8 weeks after onset of therapy with an average time of 4 weeks. Recovery after cessation of therapy was within 10 weeks. About 25% of the leukopenic or thrombocytopenic episodes did not recover. Mitomycin produces cumulative myelosuppression. Integument and Mucous Membrane Toxicity This has occurred in approximately 4% of patients treated with mitomycin.
Interactions
- No major interactions listed on the FDA label. Always consult a healthcare professional.