Vioxx: an unequal partnership between safety and efficacy

Last week’s dramatic withdrawal of the COX-2 inhibitor rofecoxib (Vioxx) is discussed in this week’s lead editorial in THE LANCET, which comments that more vigilant drug licensing is vital to prevent the endangering of patients’ health.

The relative paucity of data at the time drug’s come onto the market is a key issue for physicians. The editorial comments: ‘Doctors need to be more aware of the very preliminary nature of data, both for safety and efficacy, provided with newly licensed drugs. For rofecoxib the original safety data were based on results from approximately 5000 patients. In comparison with the 2 million people receiving the drug until last week, this is a very small number and helps to explain how an important side-effect could have been missed, and subsequent confidence in the drug misplaced. For all newly licensed drugs, confidence about safety can only be provisional’.

‘Pharmaceutical companies also have lessons to learn. Merck responded well to this latest piece of the rofecoxib jigsaw puzzle. However, the real picture of cardiovascular risk has been apparent for some time and Merck’s vigorous defence of this drug in the past was clearly an error. If the dangers associated with rofecoxib were not proven, they were certainly possible, even probable, given the available data, and it should not have been left to a small trial in a novel application to reveal them. In the end it is patients, now understandably confused by the implications of rofecoxib’s withdrawal, who will lose the most. Which drugs, they will ask, should they trust?’

The editorial concludes: ‘Finally, drug regulators must now reassess the safety and efficacy thresholds required for the licensing of a new pharmaceutical product. Clearly, this is an immensely complicated equation involving, among other factors, the nature of the condition being treated, the therapeutic strategies already available, and the perceived benefit-to-hazard ratio of the new treatment. The Vioxx story is one of blindly aggressive marketing by Merck mixed with repeated episodes of complacency by drug regulators. We need clear statements from all parties in this sorry tale about the lessons to be learned. Without more vigilant drug regulation in the future, doctors will continue to be misled and patients’ lives will continue to be endangered.’