Is it equivalent? Evaluation of the clinical activity of single agent Lipodox® compared to single agent Doxil® in ovarian cancer treatment.

BACKGROUND

In response to the critical shortage of liposomal doxorubicin (Doxil®) in the United States, the Food and Drug Administration (FDA) approved temporary importation of doxorubicin hydrochloride liposome (Lipodox®). The objective was to compare toxicity and clinical activity of Lipodox® with Doxil®.

METHODS

Recurrent ovarian cancer patients who received Lipodox® were compared 3:1 to matched control Doxil® patients who had received Doxil®. Patients were matched based on age, stage, dose, platinum sensitivity, and prior treatments from an existing de-identified database. Patients receiving combination regimens were excluded.

RESULTS

The data from 40 Lipodox® patients was compared to 120 matched control Doxil® patients. In this study, 17 (42.5%) of the Lipodox® patients were switched to Doxil®. The overall response rate Lipodox® was 4.3% (1/23) compared to 18% (20/111) in matched control Doxil® patients. In the platinum-sensitive patients, 100% progressed in the Lipodox® group compared to 78.4% in matched control Doxil® patients. The mean time to progression was 4.1 ± 2.8 months for Lipodox® and 6.2 ± 7.2 months in control Doxil®s (p = 0·25). Toxicity was similar in the Lipodox® group and control Doxil® group.

CONCLUSION

Lipodox® for treatment of recurrent ovarian cancer did not appear to have equivalent efficacy compared to Doxil®. A prospective clinical study is warranted before Lipodox® can be deemed equivalent substitution for Doxil®.