A phase II study of erlotinib (OSI-774) given in combination with carboplatin in patients with recurrent epithelial ovarian cancer (NCIC CTG IND.149).

OBJECTIVES

Approximately 50% of ovarian cancers have elevated levels of epidermal growth factor receptor (EGFR) which correlates with a poor prognosis. Preclinical evidence suggests that EGFR tyrosine kinase inhibitors (TKIs), such as erlotinib (OSI-774), may potentiate the anti-tumour effects of cytotoxic agents, including carboplatin. Blocking EGFR could thus potentially reverse drug resistance. The primary objective of the study was to assess the response rate to the addition of erlotinib in patients with recurrent ovarian cancer who were receiving carboplatin.

METHODS

Patients enrolled on this study had either local or advanced recurrent ovarian cancer with measurable disease. They may have had up to 2 prior chemotherapy regimens, one of which must have contained platinum, and they must have responded to prior platinum therapy. Patients were stratified by platinum sensitivity and were treated with erlotinib 150 mg daily on a continuous dosing schedule, and carboplatin at an AUC of 5 every 21 days.

RESULTS

Fifty patients with recurrent ovarian cancer entered the study, 33 in the platinum-sensitive arm and 17 in the platinum-resistant arm. Of patients evaluable for response, there were 14 partial responses (PR) of 30 evaluable for response (57% objective response rate (ORR)) in the platinum-sensitive arm, and 1 PR of 14 evaluable for response (7% ORR) in the platinum-resistant arm.

CONCLUSIONS

The combination of erlotinib and carboplatin was active in patients with platinum-sensitive disease, but not in platinum-resistant disease. The toxicities seen were those expected with carboplatin and erlotinib.