In a novel approach, thalidomide and bevacizumab are added to docetaxel
SAN FRANCISCO—Adding thalidomide and bevacizumab to docetaxel may hold promise for treating patients with metastatic androgen-independent prostate cancer (AIPC), investigators report.
William L. Dahut, MD, of the National Cancer Institute in Bethesda, Md., and his colleagues studied this treatment regimen in a phase II trial of 60 men with progressive metastatic AIPC with castrate levels of testosterone. All subjects had to have two consecutively rising PSA levels (at least 5 ng/mL), progressive measurable disease, and/or at least one new lesion found on a bone scan.
The men had a median age of 66 years and a median Gleason score of 8. Their median on-study PSA level was 99 ng/mL. Treatment consisted of docetaxel 75 mg/m2 plus bevacizumab 15 mg/kg on day 1 and then every 21 days as a cycle, plus thalidomide 200 mg every bedtime and prednisone 10 mg once daily. The study population underwent a median of 12 treatment cycles (range 2-47). Of the 60 patients, 58 had PSA positive disease and two patients were devoid of PSA activity.
Fifty-two of 58 patients (90%) had PSA declines of 50% or more. Forty-two patients (72%) had PSA de-clines of at least 80%. The estimated progression-free and overall survival was 18.2 and 26.7 months, respectively, which the researchers said were encouraging.
The investigators were able to evaluate 32 patients with lesions that were measurable radiographically (CT and bone scans). Their overall response rate was 63%.
With respect to toxicities, the investigators said the combination generally has been well tolerated. The toxicities associated with the regimen are as expected and appear to be acceptable, the researchers concluded. They reported findings here at the 2008 Genitourinary Cancers Symposium.