Phase II study of erlotinib (OSI 774) in women with recurrent or metastatic endometrial cancer: NCIC CTG IND-148

Abstract

5019 Background: EGFR over expression is seen in 60–80% of endometrial cancers(EC) and may have a major role in tumour growth and progression. Erlotinib is an orally active, selective inhibitor of EGFR tyrosine kinase activity. Methods: A 2 stage phase II study was performed to evaluate single agent activity of erlotinib in EC. Multinomial endpoints incorporating response and stable disease were used. Women with recurrent or metastatic EC, with measurable disease, chemotherapy naïve and up to 1 line of prior hormonal therapy were eligible to participate. Patients (pts) received single agent erlotinib at a daily dose of 150 mg continuously. A cycle was defined as 4 weeks of therapy, with response assessment every 2 cycles. Results: Twenty seven pts have been entered to date, with 25 evaluable for toxicity and 23 for response (1 cancelled before starting, 1 had only 5 days of trial drug, additional 2 pts too early for assessment). Treatment was well tolerated with 60% of pts receiving 90% of planned dose intensity. Seven had dose reductions (3 for skin toxicity; 3 diarrhea and 1 keratitis/conjuctivitis). The most common drug related toxicity was rash (2 grade(gr)3, 10 gr2 and 10 gr1). Drug related severe toxicity was infrequent with the only gr4 toxicity being an elevation of transaminases (SGOT). Grade-3 toxicities included 3 pts with diarrhea, 1 rash and pruritis, 1 non-neutropenic infection and dyspnea, plus single reports of fatigue, arthralgia, keratitis/conjunctivitis, rash, puritis and an elevation of bilirubin. There were no grade 3 or 4 hematologic toxicities. To date there is 1 confirmed partial response (PR) of disease in the mesentery and lungs lasting 10.4 mo. 12 pts have had stable disease (SD), with median duration of 3.4 mo (1.5–7.6). EGFR status using primary archival tumor tissue has been analyzed on 12 pts to date; 7 were positive, 5 were negative. Of the 7 pts who were EGFR positive, 1 had a PR, 3 SD and 3 progressive disease(PD). Of 5 who were EGFR negative, 2 had SD and 3 PD. Conclusion: Erlotinib in endometrial cancer is well tolerated. The study has fulfilled criteria to proceed stage II, with planned accrual of 30 evaluable patients. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration OSI Pharmaceuticals