ibular toxicity has also been reported. Ototoxic effects may be related to the peak plasma concentration of cisplatin. Ototoxicity can occur during treatment or be delayed. Audiometric monitoring should be performed prior to initiation of therapy, prior to each subsequent dose, and for several years post therapy.
The risk of ototoxicity may increased by prior or simultaneous cranial irradiation, and may be more severe in patients less than 5 years of age, patients being treated with other ototoxic drugs (e.g. aminoglycosides and vancomycin), and in patients with renal impairment. Variants in the thiopurine S-methyltransferase gene (TPMT) have been reported to be associated with an increased risk of ototoxicity in children treated with cisplatin (see CLINICAL PHARMACOLOGY).
Other genetic factors may also contribute to the cisplatin-induced ototoxicity.
Hematologic
Myelosuppression occurs in 25% to 30% of patients treated with PLATINOL-AQ. The nadirs in circulating platelets and leukocytes occur between days 18 to 23 (range 7.5 to 45) with most patients recovering by day 39 (range 13 to 62). Leukopenia and thrombocytopenia are more pronounced at higher doses (>50 mg/m2). Anemia (decrease of 2 g hemoglobin/100 mL) occurs at approximately the same frequency and with the same timing as leukopenia and thrombocytopenia. Fever and infection have also been reported in patients with neutropenia. Potential fatalities due to infection (secondary to myelosuppression) have been reported. Elderly patients may be more susceptible to myelosuppression (see PRECAUTIONS: Geriatric Use).
In addition to anemia secondary to myelosuppression, a Coombs' positive hemolytic anemia has been reported. In the presence of cisplatin hemolytic anemia, a further course of treatment may be accompanied by increased hemolysis and this risk should be weighed by the treating physician.
The development of acute leukemia coincident with the use of PLATINOL-AQ has been reported. In these reports, PLATINOL-AQ was generally given in combination with other leukemogenic agents.
Gastrointestinal
Marked nausea and vomiting occur in almost all patients treated with PLATINOL-AQ, and may be so severe that the drug must be discontinued. Nausea and vomiting may begin within 1 to 4 hours after treatment and last up to 24 hours. Various degrees of vomiting, nausea and/or anorexia may persist for up to 1 week after treatment.
Delayed nausea and vomiting (begins or persists 24 hours or more after chemotherapy) has occurred in patients attaining complete emetic control on the day of PLATINOL-AQ therapy.
Diarrhea has also been reported.
OTHER TOXICITIES
Vascular toxicities coincident with the use of PLATINOL-AQ in combination with other antineoplastic agents have been reported. The events are clinically heterogeneous and may include myocardial infarction, cerebrovascular accident, thrombotic microangiopathy (hemolytic-uremic syndrome [HUS]), or cerebral arteritis. Various mechanisms have been proposed for these vascular complications. There are also reports of Raynaud's phenomenon occurring in patients treated with the combination of bleomycin, vinblastine with or without PLATINOL-AQ. It has been suggested that hypomagnesemia developing coincident with the use of PLATINOL-AQ may be an added, although not essential, factor associated with this event. However, it is currently unknown if the cause of Raynaud's phenomenon in these cases is the disease, underlying v |
