ASCO 2015: Bevacizumab Combination Boosts Survival in Advanced Stomach and Esophageal Cancers
Patients whose metastatic stomach or esophageal cancers were driven by a mutated HER2 gene had markedly improved response rates and survival when bevacizumab (Avastin) was added to a standard drug combination. Scientists at Dana-Farber Cancer Institute, who led the research, will report these findings on June 1 at the 2015 ASCO Annual Meeting in Chicago (Abstract 4038).
Study Details
Of the 36 patients in the phase II trial, the median overall survival thus far is at least 21 months, reported Peter Enzinger, MD, Clinical Director of the Center for Esophageal and Gastric Cancer at Dana-Farber/Brigham and Women’s Cancer Center. The response rate was 81%, including 25 partial and 2 complete responses.
Bevacizumab, an antiangiogenic agent, was added to the combination of capecitabine and oxaliplatin chemotherapy and trastuzumab (Herceptin). This combination is known as CAPOX+B+T. Trastuzumab blocks the growth-stimulating effects of the HER2 mutation, which is present in 15% to 20% of patients with esophageal and gastric cancers.
In a previous trial, similar patients treated with a combination of trastuzumab, capecitabine, and cisplatin (but not bevacizumab) had an overall survival of 13.8 months and a 47% response rate. Several of the initial patients in the trial who began treatment as early as January 2012 are still alive, noted Dr. Enzinger.
Of the patients treated with CAPOX+B+T, tumors were found in the esophagus, stomach, and in the junction between the esophagus and stomach.
The drug combination was well tolerated, the researchers said, and 16 patients needed to have their doses modified.
“I think this combination has promise,” said Dr. Enzinger, noting that “there appears to be at least an additive effect between bevacizumab and trastuzumab.” He said he hopes that a large, randomized phase II trial can be launched to confirm the findings of this smaller study.
This research was supported by Genentech. Dr. Enzinger reported a consulting or advisory role with Taiho Pharmaceutical. For full disclosures of the study authors, view the study abstract at abstract.asco.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
