Drug Combo Safe for Lung Cancer
CancerWise - February 2009
A novel combination of carboplatin, Taxol® (paclitaxel), and the targeted therapies Avastin® (bevacizumab) and Erbitux® (cetuximab) is safe and may extend the lives of patients with advanced lung cancer, according to a recent study.
Lead author and study principal investigator Edward Kim, M.D., assistant professor in the Department of Thoracic/Head and Neck Medical Oncology, conducted the Southwest Oncology Group (SWOG) Phase II study, the first to pair the standard regimen of carboplatin, Taxol and Erbitux with Avastin. Results were presented in November at the 2008 Chicago Multidisciplinary Symposium in Thoracic Oncology.
Significance of results
Lung cancer is the leading cause of cancer death in the United States, according to the American Cancer Society. In 2008 approximately 215,000 people were diagnosed with lung cancer, and approximately 114,000 died from the disease.
The study looked to increase effectiveness of the standard regimen for lung cancer without compromising patient safety.
“Due to toxicity concerns of standard cytotoxic chemotherapy, we could not conduct a study with four chemotherapeutic agents,” says Kim, principal investigator. “But after another study showed that Avastin enhances the efficacy of existing therapy, we wanted to see whether it might improve the carboplatin-paclitaxel-Erbitux combination.”
Data in lung cancer also have suggested an enhanced effect in pairing the epidermal growth factor (EGFR) inhibitor compounds with the vascular endothelial growth factor (VEGF) inhibitor, Kim adds.
Between August 2006 and September 2007, the Phase II study enrolled 110 stage IIIB or IV non-small cell lung cancer patients. Ninety-nine were eligible for evaluation. Patients received six cycles of the four-drug regimen and continued receiving Avastin and Erbitux as maintenance therapy.
It's unique for a trial to feature a maintenance therapy combining two biologic drugs, Kim explains.
The study met its primary endpoint, safety, which was defined by frequency of pulmonary hemorrhage (bleeding), a concern related to Avastin. There were four deaths related to treatment and two due to bleeding, which is consistent with prior Avastin studies.
Adverse events such as low blood counts and neuropathy were reported in 40 patients, which is consistent with standard chemotherapy.
Secondary endpoints included response rate, progression-free survival and overall survival.
Of patients enrolled:
- 53% experienced shrinkage of their tumors
- 24% had stable disease
The median progression-free survival rate was seven months, and overall survival was 14 months. In contrast, previous studies showed an average progression-free survival rate of 5½ months and overall survival of 12 months.
"These compelling findings are the best results ever for a SWOG-based study in advanced lung cancer,” Kim says. “While results are in early stages, this four-drug combination seems to show modest, yet promising, improvement without compromising patients' safety.
"Next, we’ll analyze the tissue from this study to find appropriate biomarkers for the disease to best understand who might benefit from this drug regimen."
A biomarker analysis of this study is ongoing, and a randomized Phase III study is planned to open in 2009.
— Adapted by Mary Brolley from and M. D. Anderson news release