Four drug combination helps in lung cancer: U.S. study

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - Combining two chemotherapy drugs with two targeted therapies was safe and appeared to help patients with advanced lung cancer live longer, U.S. researchers reported on Thursday.

The combination of Roche and Co's Avastin, ImClone's Erbitux, carboplatin and paclitaxel appeared to add an average of two months to the lives of patients, from 12 months on average to 14 months, the team at the University of Texas M. D. Anderson Cancer Center said.

It was the first time two targeted therapies were used together with traditional chemotherapy in this way and M.D. Anderson's Dr. Edward Kim said the Avastin and Erbitux appeared to work synergistically.

"The rationale behind the study was the finding that Avastin enhances the efficacy of existing therapy, thereby possibly improving the carboplatin-paclitaxel-Erbitux regimen," Kim said in a statement.

"While early, this four-drug combination seems to show promising, yet modest improvement in efficacy without compromising patients' safety," Kim added.

He said his team would analyze the tumors to see if there were so-called biomarkers that can predict who would do best on this therapy.

Avastin, known generically as bevacizumab, is a monoclonal antibody, a genetically engineered immune system molecule, that targets vascular endothelial growth factor or VEGF. VEGF helps tumors grow a blood supply and Avastin is a so-called angiogenesis inhibitor that helps choke off that supply.

Erbitux, known generically as cetuximab, is also a monoclonal antibody and angiogenesis inhibitor but it targets a different blood-vessel-promoting molecule called epidermal growth factor receptor or EGFR.

The two older chemotherapy drugs, paclitaxel, sold under the brand name Taxol and carboplatin sold under the brand name Paraplatin, both by Bristol Myers Squibb, kill tumor cells directly.

Kim told the 2008 Chicago Multidisciplinary Symposium in Thoracic Oncology that his team tested 110 patients with stage 3 or 4 lung cancer in a phase II safety and efficacy trial.

The patients got six cycles of all four drugs and then as maintenance continued infusions of Avastin and Erbitux.

Four patients died from the treatment -- Avastin is known to sometimes cause internal bleeding -- and 40 patients had the usual side effects such as nerve pain and low blood counts.

But 53 percent had their tumors shrink and 24 percent had stable disease. On average patients enjoyed seven months before their tumors started growing again and lived 14 months.

Patients who previously got three drugs without Avastin lived an average of 5.5 months before their tumors started to grow again and 12 months overall.

Lung cancer is the leading cause of cancer death globally, with 1.2 million deaths a year and 114,000 annually in the United States, according to the American Cancer Society.