Valrubicin

Valrubicin(AD-32) is an N-trifluoroacetyl, 14-valerate derivative of the an thracycline doxorubicin. It has antineoplastic activity which probably resu lts from interference with nucleic acid metabolism by the drug. Valrubicin entered individual cells more rapidly than doxorubicin in vitro. When valrubicin was administered intravesically to patients with bladder c ancer, cytotoxic concentrations of the drug penetrated the superficial musc le layer of the bladder. Complete response rates were 18 and 29% in patients with carcinoma in situ of the bladder which was refractory to intravesical BCG in 2 noncomparative trials of prophylactic intravesical valrubicin. In patients with recurrent superficial papillary tumours, the complete response rate was 46%, Adverse events were generally transient in patients who received intravesic al valrubicin. Bladder irritation occurred in 88% of patients. Systemic abs orption of intravesically administered valrubicin was minimal. Accordingly, systemic adverse events generally occurred in less than or equal to 5% of patients. Valrubicin was less toxic to chick embryos and haematopoietic stem cells in vitro and produced a lower incidence of cardiotoxicity in rabbits, compare d with doxorubicin.