Big gun clinical trials versus the intuitive leap in new medical therapy discovery...
POSTED ON 6/1/2010 IN Research BY Christopher Centeno
This is a piece I wrote awhile back on the differences between the two new therapy discovery pathways in medicine, thought it would make an interesting post... “In theory, there is no difference between theory and practice. But in practice, there is.” Sun Tzu Medicine has two arms for new therapy discovery, the pragmatic medical practice arm and the research based, theoretical arm. These two pathways have both yielded ground breaking discoveries. For example, great medical advances such as coronary bypass surgery, in-vitro fertilization, and modern joint surgery have all been birthed by responsible physician investigation. The research arm has provided such breakthroughs as modern antibiotics, anti-hypertensive drugs, and aspirin. There are several key differences between these two arms of treatment discovery, the first being public health risk. Medical practice discoveries are generally defined by unique one on one medical practice risks such as a surgeon who tries a variation on a tried and true surgical technique or has a new instrument made. The risk is to one patient. Drug research risks are generally one on many mass production risks such as the development of a new antibiotic. In this case, the studies place many patients at risk with one clinical decision (let's treat 1,000 patients with disease X with drug Y). These two pathways are also differentiated by their innovation characteristics. Medical practice discoveries tend to be intuitive, faster to adapt to change, and are often a response to problems encountered by clinicians. Research discoveries tend to be methodical and based on basic research findings. Also, due to the nature of research designs that require testing in hundreds to thousands of patients, the basic research pathway is slow to adapt to change. However, the generalizability of research findings to large populations generally draw more powerful conclusions than many medical practice discoveries which may or may not ever be tested in randomized controlled trials. By analogy, if medical practice represents the speedboat of therapy discovery, theoretical research is the aircraft carrier. The practice discovery path, like the speedboat, is quicker, but lacks big firepower, while research innovation, like the aircraft carrier, is slower, but has ample firepower. At its most basic, physicians often unknowingly participate in the practice discovery process through prescribing drugs off-label or off indication (in alternate doses or for different diseases than the research based conclusions). The courts have weighed in on this issue by describing a public benefit to this practice discovery pathway. In United States v. Evers, 453 F. Supp. 1141 (M.D. Ala. 1978), the court sided with a physician who was prescribing drugs in this manner. The Court noted that a drug's package insert is not the most up-to-date information on the drug's uses and that new uses are often discovered, reported through medical journals or seminars, and may become widely used in the medical profession; however, the drug manufacturer may not have sufficient financial or other interests to pursue FDA approval for the new uses. Further, if a doctor must prescribe and treat only within “federally sanctioned” methods, this would result in medical stagnation at the best, as physicians await drug manufacturers' initiative and FDA approval. The court reasoned, “A free, progressive society has an enormous stake in recognizing and protecting this right of the physician.” Recently, proponents of Evidence Based Medicine (EMB) have suggested that physicians only practice within the parameters defined by the research centered pathway. While this method of medical care has its advantages (such as large scale generalizability showing evidence of efficacy), it's also very rigid and lacks the flexibility and innovation characteristics of medical practice discovery. For instance, a therapy or drug tested for efficacy in patients with hypertension through the research pathway may or not be effective in patients with both diabetes and hypertension. Also, the drug may lose its efficacy when multiple other drugs are introduced. This is because the research pathway requires isolation of a specific variable for research purposes, while real patients by their nature are multivariate. By comparison, the physician discovery pathway allows for the multiple variables, as physicians experience this environment every day. For example, they frequently adjust doses, limit or exclude certain therapies for patients based on clinical experience, or make intuitive leaps about new therapies based on years of clinical observation. This is one reason this flexible practice discovery pathway adds societal benefit; it allows much faster adaptation to the multiple variables seen in real medical practice. In summary, there are two pathways of therapeutic innovation, represented by the speedboat (medical practice discovery) and the aircraft carrier (research discovery). One pathway can lead to the other, as it's common for doctors who discover new techniques to test these via controlled trials. The opposite is also true, as research findings that seem to hold great promise in controlled trials often fail to work as well in real world medical practice. This last problem is very common, as physicians in the field often find that the single variable study design doesn't apply to their multivariate patient populations. There is societal benefit to make sure that both of these discovery pathways thrive, as both benefit medical innovation, or as Sun Tzu has said, “In theory, there is no difference between theory and practice. But in practice, there is.”
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