Referrals to phase I clinical trials in a gynecologic oncology unit

Previous reviews of phase I clinical trials report limited response rates. Development of novel biologic agents and trials designs have increased these rates. A contemporary appraisal of phase I clinical trials in gynecologic malignancies could help validate these findings.

Retrospectively reviewed records for 410 patients with gynecologic malignancies treated in a phase I unit, January 1999 to October 2012. Patient characteristics and treatment outcomes were abstracted and analyzed.

Patients enrolled in 43 different phase I trials, 17 phase Ia, 17 phase Ib dose escalation and 9 dose expansion. 9 trials (21%) investigated unique cytotoxic delivery methods, 15 (35%) conventional cytotoxic plus novel agents and 19 (44%) novel agents alone. For patients treated in the first-line setting, 90 (74.4%) achieved CR, 20 (16.5%) PR, 9 (7.4%) SD and 2 (1.7%) PD, yielding an overall response rate of 90.9%. In patients treated for recurrent disease, 2 (1.6%) achieved CR, 11 (8.9%) PR, 57 (46.0%) SD and 54 (43.5%) PD, yielding a response rate of 11% and an overall clinical benefit rate of 57%. Response rate for molecular targeted therapies was 11.5% with an overall clinical benefit rate of 46.2%. Patients with prior anti-angiogenic exposure had comparable median PFS to those who had not been previously exposed (3.5 vs. 4.0 months, p = 0.29).

Results support referral of gynecologic cancer patients for phase I clinical trials. Patients with advanced, heavily pretreated disease fare at least as well as they do on phase II trials and a proportion of them can attain an objective response or stabilization of their disease.