Merck KGaA sifts through Erbitux safety data

Merck KGaA is taking its magnifying glass to the data on Erbitux safety. That's because European regulators, in reviewing and rejecting the drug for lung cancer earlier this month, uncovered an increase in "cardiac events" in older lung-cancer patients treated with Erbitux. The incidence appeared greatest in high-risk patients with existing heart problems, Bloomberg reports.

Merck spokeswoman Phyllis Carter tells the news service that the company is expected to follow up by looking at the data on patients given Erbitux for other indications. The drug is approved to treat colon cancer and head-and-neck cancers, and Merck doesn't expect the labeling to change for those uses.

But that all depends on what the company finds when it analyzes the data, and even if new labeling just affects off-label use--or potential new uses--that could hurt. Analysts worry that any link to heart problems might force the sort of labeling change that would significantly eat into sales. Citigroup analyst Mark Dainty tells Bloomberg that, if a cardiac risk is found, the drug's sales could drop by as much as $534 million. "Risk exists that a stronger label with warnings may result," the analyst writes.

- read the Bloomberg story