Changing the drugs' labels won't be a too damaging to the companies in the long run. They've probably already lost many patients, because doctors already know the initial results and have begun testing patients. With the label change, the companies will be able to tout the data from the normal K-ras patients, for whom the results suggest that the drugs work better than chemotherapy. While they will likely lose some colon-cancer patients, they should also pick up even more normal K-ras patients who might have used other drugs -- or so ImClone believes.
Actually, the big beneficiary of a label change will be the companies that test for mutations in K-ras: Bio-Reference Laboratories
As society tries to lower the cost of health care, it may increasingly begin to eliminate the use of drugs in patients who won't benefit. Personalized medicine is still in its infancy, but it's an emerging industry that should be huge in the long run.