Prescription drugs: A choice between safety and life

Drug safety and efficacy decisions are far from easy. But when a drug seems to offer a potential cure, should the U.S. Food and Drug Administration (FDA) err on the side of safety or on the side of the patient, asks Henry Miller, a physician and fellow at the Hoover Institution.

It is the rule rather than the exception that prescription drugs have efficacy and serious safety issues, says Miller. Consider:

Antimetabolites, like experimental cancer drug BCNU, are poisons that are intended to be more toxic to cancer cells than normal ones; so, it is not surprising that their side effects are often serious and even life-threatening.

Aldesleukin – which offers new hope to kidney cancer and malignant melanoma victims – is highly effective in a small proportion of patients but exhibits significant toxicity.

Antibiotics like chloramphenicol and gentamicin can also manifest significant toxicity.

But in the case of Tysabri – a multiple sclerosis (MS) drug – the appearance of progressive multifocal leukoencephalopathy (PML) in three patients caused manufacturers to withdraw the drug from the market; however, many patients and neurologists claim that this was premature, says Miller.

According to the New England Journal of Medicine (NEJM):

In a study of 1,000 patients that compared Tysabri to placebo, the drug cut the rate of clinical relapses by 68 per cent, reduced by 83 per cent the number of new or expanding brain lesions found by MRI and slowed the clinical progression of disease.

Similar results were obtained in a second trial.

Another study found no additional cases of PML in more than 3,000 patients who had participated in clinical trials of Tysabri.

The "safety" of a drug is a relative thing. Safety and efficacy, the two criteria required for marketing approval of a drug, are inextricably linked, but in some cases, the patients' freedom to choose should win out, says Miller.

Source: Henry I. Miller, Paternalism Costs Lives, Wall Street Journal, March 2, 2006; based upon: Chris H. Polman et al., A Randomized, Placebo-Controlled Trial of Natalizumab for Relapsing Multiple Sclerosis, New England Journal of Medicine, March 2, 2006.

For text (subscription required): http://online.wsj.com/article/SB114125841380186971.html

For NEJM abstract: http://content.nejm.org/cgi/content/abstract/354/9/899

For more on Health: http://www.ncpa.org/iss/hea/

FMF Policy Bulletin/ 14 March 2006