DaunoXome Shows Promise as Breast Cancer Treatment

Data presented at the 18th Annual San Antonio Breast Cancer Symposiumin Boulder, Colorado, shows that moderate-dose DaunoXome, NeXstarPharmaceuticals' liposomal formulation of daunorubicin, is well-toleratedand has promising efficacy in treating advanced breast cancer.Moreover, the limited toxicity observed in this trial, particularlythe absence of cardiotoxicity, suggests that DaunoXome may beuseful in ameliorating the side effects that accompany high-doseanthracycline-based chemotherapy for metastatic breast cancer.The data, generated in a phase II study funded by NeXstar, werepresented by P.S. Hupperets, MD, of the Akademisch Ziekenhuis,in Maastricht, The Netherlands.

In the study, 11 women with previously untreated, newly diagnosedmetastatic breast cancer received DaunoXome at a dose of 100 mg/m²every 3 weeks for as long as 24 weeks. Even at this moderate dose,three patients (27%) developed a partial response, seven (63%)had stable disease, and one patient (10%) experienced no therapeuticbenefit. Toxicity was minimal; no patient lost hair, and onlytwo patients reported mild nausea. Six patients showed evidenceof bone marrow suppression, which did not limit treatment andwhich recovered without supportive therapy. No patient exhibitedsigns of cardiotoxicity.

"These data demonstrate that moderate-dose DaunoXome therapyproduces the same kind of response rates as conventional single-agentdoxorubicin therapy, but a much improved side-effects profile,"said Michael E. Ross, NeXstar's vice president for medical andregulatory affairs. "We believe that these results bode wellnot only for the expanded trials we're conducting in breast cancer,but for the other solid tumor indications in which DaunoXome isbeing tested. We also believe that the absence of cardiotoxicitysuggests that DaunoXome may play an important role in replacingconventional anthracyclines in high-dose, multiple-agent chemotherapyregimens." Such studies are currently in progress.

DaunoXome has already been approved in the United Kingdom andSweden as a primary therapy for advanced Kaposi's sarcoma in HIV-positivepatients and is awaiting final approval in the United States forthe same indication. In addition to the phase II study in breastcancer, NeXstar is conducting phase II trials with DaunoXome insmall-cell lung cancer, non-small-cell lung cancer, hepatocellularcancer, adult and childhood leukemia, brain tumors, bladder cancer,and lymphoma.