The US FDA has recently approved the first personalized therapy — cetuximab (Erbitux) to treat colorectal cancer. In India, almost 42,340 new cases of colorectal cancer (CRC) are estimated to occur in 2012. Colorectal cancer is a cancer that develops in the colon or the rectum; both are parts of the large intestine.
The world’s top drug regulatory agency has given full approval to the drug as initial treatment against the advanced stage of cancer. Erbitux should be given in combination with the current chemo therapy. Presently, colorectal cancer is being managed with a treatment involving three drugs: irinotecan, 5-fluorouracil and leucovorin.
Erbitux is a biologic drug. Unlike chemically produced drugs, biologics are considered safer with far fewer side-effects as they are man-made versions of naturally-occurring body proteins. Before taking Erbitux, the patient should undergo a KRAS gene test authorized by the regulator to predict whether the drug will work for the person.
The FDA approved screen test is aimed to weed out the patients with the K-RAS gene mutation who are unlikely to respond to Erbitux treatment. The FDA nod for the new indication is based on data from a large scale patient study titled CRYSTAL (Cetuximab combined with iRinotecan in first-line therapY for metaSTatic colorectAL cancer) conducted outside the US, said an official release announcing the approval.
“The totality of the data from CRYSTAL, along with data from other ERBITUX trials, provide compelling and consistent evidence of the benefit of ERBITUX in the treatment of KRAS mutation negative (wild-type) EGFR-expressing mCRC,” said Dr Ashok Vaid, Chairman, Medanta Cancer Institute, Gurgaon.
Metastatic colorectal cancer occurs when the disease has spread to at least one distant organ and tissues, such as the liver, lungs, lining of the abdomen or ovaries. Generally, only 12 per cent of patients affected with this form of the disease survive beyond five years.
However, once they were treated with cetuximab (Erbitux), combined with the chemotherapy currently in use, the patients’ survival rate had gone up to as much as 20 per cent and with significant decrease in the risk of disease progression compared to patients receiving only the present line of chemotherapy, found an analysis of the study data against the advanced stage of cancer centres.
As a disease, cancer is diverse in character and not all patients suffering from the metastatic colorectal cancer present themselves with the same tell-tale symptoms and signs. This underscores the need for a personalised treatment approach. For colorectal cancer patients who are diagnosed at the late stage, it is devastating. Getting them tested for the genetic status at the time of diagnosis provides patients, physicians, and their families with a new understanding in how to best manage their care, the release said.
EH News Bureau