Excluding Freak Detour, ImClone's Gain is Modest

The FDA pointed out Thursday that although Erbitux has not been shown to extend patients' lives, tests say the drug can shrink tumors in some patients and delay tumor growth in other patients, especially when the drug is used with other cancer medications.

Colorectal cancer is the third most common cancer affecting U.S. men and women, says the federal Centers for Disease Control and Prevention. About 147,500 new cases were diagnosed last year. The agency says cancer of the colon and rectum is the second biggest cancer killer.

"FDA believes it is crucial for cancer patients to have many proven treatment options in their battle against this disease," said Mark B. McClellan, the FDA commissioner in announcing his agency's approval of the drug.

The FDA said the original Erbitux application -- in which results of several tests were submitted to the agency between June 28, 2001 and Oct. 31, 2001 -- was rejected because certain data about the drug's safety and effectiveness was missing. The agency also said that about half the patients in the original tests had not failed the approved treatments for colon cancer.

When ImClone resubmitted its request, the agency said the company provided the results of a "large, well-run trial" as well as results from the earlier tests. The agency said ImClone was able to successfully collect "substantial amounts" of the missing data related to its first application.

Two other studies are under way to assess Erbitux's ability to stop the progression of colorectal cancer and to extend the lives of patienets with advanced colon cancer.

Erbitux appears to work by targeting a natural protein called epidermal growth factor receptor (EGFR) on the surface of cancer cells, interfering with their growth.

For patients with tumors that produce EGFR and who don't respond to existing colon cancer treatments, the FDA says the combination of Erbitux and the standard treatment irinotecan shrank tumors in 22.9% of patients and delayed tumor growth by 4.1 months. Erbitux alone led to tumor shrinkage in 10.8% of patients and delayed tumor growth by 1.5 months.

Erbitux was first approved in Switzerland on Dec. 1, 2003, for colorectal cancer patients who no longer responded to traditional chemotherapy.

The application to Swiss medical authorities was made by ImClone and its partner, Merck KGaA, of Germany, which licensed the rights in 1998 from ImClone to market the drug outside of the United States and Canada. The German company is not related to Merck in the United States.

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