Nearly 80% of advanced colorectal cancer patients who progressed to surgery while taking Roche’s Avastin (bevacizumab) and standard chemotherapy were able to have their metastatic lesions completely removed, a Phase IV clinical trial has shown.

Results from First BEAT, a post-marketing, community-based trial that has so far enrolled 1,965 patients in 41 countries with primarily inoperable metastatic colon cancer, were presented at the European Cancer Conference (ECCO) in Barcelona, Spain this week.

Of the 215 patients in the data analysis – 11.5% of a 1,914-patient dataset – who became eligible for, and underwent, surgery with curative intent while on Avastin plus commonly used fluoropyrimidine-based chemotherapy regimens, successful, complete removal of the metastatic lesions was achieved in 170 or 79%.

As expected, Roche reported, the best outcomes were seen in a subgroup of patients with metastatic disease confined to the liver. Of these 704 patients, 102 (14.5%) had surgery with curative intent and complete resection of liver metastases was achieved in 81. The data analysis found no increase in wound-healing complications or bleeding incidents compared with historical controls.

The primary endpoint for the First BEAT trial, which completed enrolment in February 2006, was Avastin safety. General efficacy and surgery with curative intent were preplanned secondary endpoints, with data collected prospectively. Efficacy data from First BEAT continue to be evaluated, and further presentations are expected at forthcoming oncology conferences.

Patients in the Phase IV trial received Avastin in combination with standard first-line chemotherapy, the most common regimens being FOLFOX (5-fluorouracil + oxaliplatin), XELOX (capecitabine + oxaliplatin), FOLFIRI (5-fluorouracil + irinotecan) and Xeloda (capectitabine). The patients’ suitability for potentially curative surgery was assessed during the course of treatment.

According to Roche, the success rate with patients on Avastin who were eligible for surgery was superior to that previously observed in trials with other biological/chemotherapy combinations.

“The complete resection of metastatic lesions is the only option for cure in patients with metastatic colorectal cancer,” noted Dr Mondher Mahjoubi, global head of medical affairs for oncology. “The high rates of successful, curative surgery achieved with Avastin plus standard chemotherapy are impressive, especially because First BEAT is a trial looking at a general, real life patient population.”

Colorectal cancer was the first approved indication for Avastin, granted in the US in February 2004 and then Europe in January 2005. Roche has since added lung and breast cancers to the labelling, while a comprehensive clinical programme is looking at Avastin in a range of tumour types (e.g., pancreatic and ovarian cancers, renal cell carcinoma) and settings.

Colorectal cancer is the third most common form of cancer, with around one million new cases diagnosed worldwide each year. It is estimated that more than 50% of people diagnosed with colorectal cancer will die of the disease.