Stability of mitomycin C in different infusion fluids: Compatibility with heparin and glucocorticosteroids

Introduction: Mitomycin C (Mutamycin) stability and compatibility was analyzed by reverse-phase high performance liquid chromatography (HPLC). Methods: The drug was reconstituted in sterile water for injection USP, 0.9% sodium chloride for injection USP, 5% dextrose injection USP and lactated Ringer's injection USP. Samples were stored for vari ous times at —20°C, 4°C and 25°C in both glass and plastic (polyvinyl chloride) containers. Results: Mitomycin C was shown to be stable (> 90% remaining for 5 to 7 days at room temperature in nondextrose containing infusion fluids. Greater stability was noted at drug concentrations ≥ 0.4 μg/mL and at reduced temperatures. In 5% dextrose solutions, stability was highly dependent upon pH: 3.4 hours at pH 4.7 and slightly over 24 hours at pH 5.5. Non-linear decomposition in dextrose was due to a slow increase in solution pH after adding mitomycin C. There were no stability differences for glass or plastic containers. Mitomycin was shown to be stable for prolonged periods when mixed with dexametha sone sodium phosphate (T 90% > 2 days), with hydro cortisone sodium succinate (T90% > 7 days) or with sodium heparin (T 90% > 2 days). Within these times, the concentrations of corticosteroids (measured by HPLC) and heparin (measured by bioassay) did not significantly decline. Conclusions: Mitomycin C demonstrates pro longed stability in nonacidic infusion fluids. Long- term storage in dextrose-containing solutions should be avoided, but short-term admixture with heparin and corticosteroids is feasible.