Phase II trial of temsirolimus and bevacizumab for initial recurrence of endometrial cancer.

Abstract

5025 Background: We report the interim results of the endometrial arm of a multi-tumor protocol using temsirolimus and bevacizumab in endometrial cancer (EMCA) patients at the time of their initial recurrence. The primary aim of this trial is to assess treatment efficacy in terms of both confirmed tumor response and 6-month progression free survival (PFS). Methods: Women with a performance status of 0 or 1 who have had their first recurrence for EMCA were eligible. Subjects who had chemotherapy as part of their adjuvant treatment after front line surgical staging were also eligible. The regimen included Temsirolimus 25 mg IV weekly followed by bevacizumab 10mg/kg IV on days 1 and 15 of a 28 day cycle. A modified two-stage Simon design with fixed sample size was adopted with the null hypothesis being that the true tumor response rate is at most 25% and the true 6 month PFS rate is at most 50%. Results: We enrolled 26 evaluable subjects to the first stage of which one did not proceed with treatment. The median age at enrollment was 60 (range 40-80). 22 (85%) were white and 19 (73%) were not Hispanic/Latino. 19 (73%) of subjects had prior raditation therapy, with 4 having a prior para-aortic boost. 5 (20%) subjects had a confirmed PR and 12 (48%) were progression-free at 6 months, which fell short of the futility stopping rule. An additional 5 (20%) subjects had a best response of confirmed SD, so 10 (40%) had overall clinical benefit from this regimen. AEs attributable to treatment were modest and included 16 grade 3 adverse events, of which the most common ones included hypertension, hyperglycemia, and neutropenia. There were 2 grade 4 events that were possibly treatment related including a duodenal perforation and an anorectal infection. Conclusions: While there was clinical benefit of this regimen in women at the time of their first recurrence of EMCA, the combination of temsirolimus and bevacizumab did not achieve our prespecified efficacy assumptions. This differs from what has been reported with this combination as a second line therapy for recurrent EMCA, where prespecified response assumptions differ. Also, the regimen had comparable safety and toxicity to other cytotoxic chemotherapy regimens used in this setting.