Some of the views expressed in the following notes on newly approved products should be regarded as preliminary, as there may have been limited published data at the time of publication, and little experience in Australia of their safety or efficacy. However, the Editorial Executive Committee believes that comments made in good faith at an early stage may still be of value. Before new drugs are prescribed, the Committee believes it is important that more detailed information is obtained from the manufacturer's approved product information, a drug information centre or some other appropriate source.
6 mg/mL in 5 mL vials
Indication: ovarian cancer
This chemical is extracted from the bark of the Pacific yew tree (Taxus brevifolia). As it disrupts cell division, paclitaxel has been studied as an anticancer drug.
Paclitaxel is given by intravenous infusion and is rapidly distributed to the periphery. The half-life is 6-13 hours and elimination is thought to be mainly by liver metabolism.
The drug is approved for use in patients with meta static ovarian carcinoma if standard therapy fails. Response rates in these patients are low and it is unknown if paclitaxel has any advantages over existing treatments.
Although paclitaxel is a 'natural' substance, it is cytotoxic and can cause serious adverse effects. Severe hypersensitivity can occur and all patients need premedication to cover this possibility; a corticosteroid, antihistamine and H2 antagonist are recommended. The dose-limiting toxicity is neutropenia which develops in approximately 70% of patients. Anaemia occurs in 90% of patients, but thrombocytopenia is less frequent. Approximately half of the patients will develop a peripheral neuropathy, although this usually improves after treatment is discontinued. Other adverse reactions include alopecia, hypotension, bradycardia, nausea and vomiting.
More study is required to define the clinical use of paclitaxel.
