A recent phase III study indicates that for patients with recurrent epithelial ovarian cancer, treatment with pegylated liposomal doxorubicin (PLD, Doxil®) significantly prolongs survival when compared to treatment with the drug topotecan.
Ovarian cancer is a malignancy that arises from various different cells located within the ovaries. Ovarian cancer accounts for 4 percent of cancers among women and is the fifth leading cause of cancer related deaths. Unfortunately, most ovarian cancers are not detected until the disease has progressed into the upper abdomen or other sites in the body. Currently treatment consists of surgery, chemotherapy and sometimes radiation. First-line treatment of ovarian cancer often involves platinum-based chemotherapy drugs. However, if the cancer recurs after the initial treatment with platinum chemotherapy, other chemotherapeutic drugs may be used.
Doxorubicin is a chemotherapy drug that has been use for many years to treat ovarian cancer as well as many other types of cancers. Pegylated liposomal doxorubicin (PLD) consists of fat bubbles (liposomes) that contain doxorubicin, as well as an additional protective layer of glycol strands that protect the liposomes. When doxorubicin is administered, normal cells as well as cancer cells are affected, and then the drug is quickly excreted by the body. Pegylated liposome doxorubicin is designed to stay in the blood much longer due to the protective mechanisms of the drug’s design. This extended activity allows for increased exposure of the cancer cells to the chemotherapy. In addition, because the PLD is slowly released over time, treatments are needed less frequently than with doxorubicin.
In this recent study, 474 patients with epithelial ovarian cancer who had recurrent disease or who had failed treatment with platinum-based chemotherapy were randomized to 50mg/m2 of PLD every 28 days or 1.5mg/m2/day of topotecan for 5 days every 21 days. Nearly all of the patients (70%) had had prior treatment with platinum and taxane-containing chemotherapy regimens.
The average overall survival among the 239 patients treated with PLD was 63 weeks. The average overall survival for the 235 patients that received topotecan was 60 weeks. These results were consistent among patients who did not have an anti-cancer response to initial treatment with platinum-based drugs, as well as among the patients who had responded to prior platinum chemotherapy. However, further analysis revealed that patients who had responded to previous platinum-based chemotherapy and were subsequently treated with PLD had a 30% reduction in risk of death. For the subgroup of patients who had responded to previous platinum-based therapy, the average survival for the PLD group was 108 weeks compared to 70 weeks for the patients treated with topotecan.
Researchers concluded that PLD is the only non-platinum-based chemotherapy that has produced a distinct survival advantage and should be the first choice for patients who have failed platinum chemotherapy or who have recurrent disease after receiving platinum-based chemotherapy. Patients are encouraged to speak to their physician regarding treatment options.
Reference: Gordon A, et al. Long-Term Survival Advantage for Recurrent Ovarian Cancer Patients Receiving Pegylated Liposomal Doxorubicin (PLD): Results of a Phase 3 Randomized Study. Proceedings from the Chemotherapy Foundations Symposium XXII: Innovative Cancer Therapy for Tomorrow. Presented November 11, 2004. Phoenix, AZ. Abstract #32.