The following originally appeared on The Upshot (copyright 2018, The New York Times Company).
We spend many billions of dollars each year on the discovery and development of new drugs, but almost none of it addresses two crucial questions: How do these new therapies compare with already known ones? What are the relative benefits and harms in a particular situation, for a person like you?
Such questions can best be answered by comparative effectiveness research.
To get approval from the Food and Drug Administration, drugs must be proved both effective and safe. The costs of doing this are significant, and they are most often borne by the pharmaceutical industry.
But the F.D.A.’s bar, while meaningful, often isn’t very useful for what physicians and patients really care about every day: how effective and safe drugs are compared with one another.
Consider antibiotics. In my work as a pediatrician, questions about their use come up a lot. Which drug is the best first-line therapy for which common illnesses? We don’t know. How long should we treat for different infections? We don’t know. What are the relative trade-offs between benefits and side effects in different patients in different circumstances? We don’t know.
The questions we need answered are legion. All the guidelines and practices we have are best guesses.
Comparative effectiveness research can take on many forms and involve more than drugs.
Because of a trial published in The American Journal of Preventive Medicine, we know that an intensive lifestyle intervention works better than metformin to promote weight loss.
A study published in JAMA Pediatrics last year showed that adding individual health coaching to enhanced primary care reduced pediatric obesity, but no more than enhanced primary care alone.
A comparison of different levels of insurance published in The New England Journal of Medicine showed that enhanced drug insurance coverage led to increased medication adherence, lower patient spending and lower rates for a first major vascular event (like a heart attack or stroke), with no increased overall health care spending.
A Blood Pressure Study
We know that high blood pressure is both terribly prevalent and a significant risk factor for cardiovascular disease. We also know that there are a lot of drugs out there, all F.D.A.-approved, that can help reduce this risk by better controlling blood pressure. But which is best?
This question isn’t new. In 2002, the results of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial — a comparative effectiveness trial — were published in JAMA.
Participants had to be at least 55, have hypertension and have at least one other risk factor for coronary heart disease. They were randomly assigned to take one of four drugs, each with an entirely different mechanism, representing a different class of drugs.
Chlorthalidone is a diuretic, or a drug that increases urine output. Amlodipine, a calcium channel blocker, causes blood vessels to relax and widen, and lowers the heart rate. Doxazosin does the same by blocking the effects of adrenaline on muscles throughout the body. Lisinopril blocks the enzyme angiotensin, which tightens blood vessels, leading to lower blood pressure. All the patients were tracked for four to eight years.