ROCKVILLE, MarylandThe US Food and Drug Administration (FDA) has approved Amgen's Vectibix (panitumumab) for the treatment of patients with colorectal cancer that has metastasized following standard chemotherapy. Vectibix, a fully human monoclonal antibody that binds to the epidermal growth factor receptor (EGFR), received an accelerated approval after showing effectiveness in slowing disease progression and, in some cases, reducing the size of the tumor.
"Colorectal cancer is the third most common cancer and the third leading cause of cancer mortality in the United States," said Steven Galson, MD, director of FDA's Center for Drug Evaluation and Research. "This approval adds a treatment option for patients with an advanced stage of a disease that can be life-threatening." FDA approved Vectibix based on the results of a randomized, controlled clinical trial of 453 patients with metastatic cancer of the colon and the rectum after undergoing treatment with chemotherapy regimens containing fluoropyrimidine, oxaliplatin (Eloxatin), and irinotecan (Camptosar).
The mean time to disease progression or death in patients receiving Vectibix was 96 days vs 60 days in patients receiving the best standard supportive care. In addition, 8% of the patients on Vectibix experienced a tumor shrinkage that in some cases exceeded 50% of the pretreatment size of the tumor. Both study groups showed similar overall survival.
Under the accelerated approval program, drugs for serious and life-threatening diseases can be made available earlier in the development process if a promising effect of the drug is observed. As part of the approval, Amgen committed to conduct a postmarketing trial to show whether the antibody improves survival in patients with fewer prior chemotherapies.
The most serious adverse events in the studies of Vectibix included pulmonary fibrosis, severe skin rash complicated by infection, infusion reactions, abdominal pain, nausea, vomiting, and constipation. The most common adverse events associated with Vectibix included skin rash, fatigue, abdominal pain, nausea, and diarrhea.
Amgen said it expects Vectibix to be commercially available in early-to-mid October. The company has also submitted marketing applications to the European Medicines Agency, Health Canada, Australia, and Switzerland.
Amgen Oncology Assistance
In conjunction with the approval, the company has announced plans to launch a patient assistance program, Amgen Oncology Assistance (AOA), designed to ease the financial burden of cancer treatments on patients and their families. Patients who are uninsured, underinsured, or unable to afford their insurance co-payments will be able to receive help obtaining financial support for Amgen's cancer medications. This program also includes a 5% cap on out-of-pocket co-payments for cancer patients receiving Vectibix regardless of income or insurance status.