US drug firm Schering-Plough has announced results from a phase III study that showed maintenance chemotherapy with Caelyx® (pegylated liposomal doxorubicin hydrochloride) significantly prolonged time to progression (TTP) in patients with metastatic breast cancer with infrequent and manageable clinical toxicity after first-line chemotherapy.
These data were presented at the 43rd Annual Meeting of the American Society of Clinical Oncology.
Lead investigator Prof Emilio Alba, of Virgen de la Victoria University Hospital in Málaga, Spain, said: “While standard chemotherapy has proven effective for patients with metastatic breast cancer, their response is short-lived and the time to progression is brief. The results from this study showed a significantly improved time to progression (13.2 months) in patients treated with Caelyx versus the observational arm (10.2 months).”
The Spanish cooperative group, Grupo Español de Investigación en Cáncer de Mama (GEICAM), conducted the multicentre phase III study at seven different sites throughout Spain.
Of 288 patients with metastatic breast cancer registered for the trial, 155 who had responded to initial therapy or had stable disease were randomised to receive Caelyx or to observation. Patients receiving therapy received a regimen of Caelyx at 40mg/m2 once every four weeks for six therapy cycles. Patients in the Caelyx arm experienced a median improvement in time to progression of three months (13.2 months versus the observational arm of 10.2 months; p=0.0005).
The patients in the study had a median age of 57, and had adequate bone marrow, renal, hepatic and cardiac function. These patients had experienced either complete response, partial response or had stable disease. Patients received induction chemotherapy with three cycles of anthracycline followed by three cycles of taxane, and were then randomly assigned to either the Caelyx or the observation arm.
Incidences of nausea/vomiting and alopecia were low and manageable; 21% of patients experienced grade 1 or 2 nausea/vomiting and 29% experienced alopecia. Importantly, neither clinically relevant left-ventricular ejection fraction (decrease heart function) nor clinical congestive heart failure was observed.
Dr Robert Spiegel, chief medical officer and senior vice-president of the Schering-Plough Research Institute, commented: “The study results are promising and suggest the potential value of Caelyx in the management of metastatic breast cancer. Further evaluation is indicated to confirm that Caelyx is effective and safe for select metastatic breast cancer patients who are at increased cardiac risk.”
The current approved dosage of Caelyx in metastatic breast cancer is 50mg/m2, every four weeks. To manage certain adverse events, such as palmar-plantar erythrodysaesthesia, the dose may be reduced.
Schering-Plough Corporation press release, 3/6/2007