Surrogate Markers

In 2003, the FDA approved a lung cancer drug called Iressa, but not because the medicine helped patients live longer. Instead, the agency endorsed the drug based on the fact that it reduced the size of tumors in about 10 percent of patients. This “surrogate” measure was expected to predict future increases in survival time. But it didn’t. A subsequent trial found that Iressa did not prolong patient lives. And in 2012 — after nearly a decade on the market at a cost to the US health care system of around $285 million — the FDA, at the manufacturer’s request, revoked the drug’s approval.

This is a cautionary tale of what can happen when regulatory decisions are based on proxy measures without proof that drugs are extending lives. In the case of Iressa, the FDA eventually corrected course and pulled the ineffective drug. But a new study suggests that many more cancer agents of questionable benefit remain on the market — even as Congress is debating a bill that would increase use of surrogate measures to approve drugs.