FDA Commissioner Scott Gottlieb is making plans to compel pharmaceutical firms to test the safety and efficacy of prescription opioids, an area where research is surprisingly lacking.
"We are going to impose a mandate on existing products … to answer the question that people have been posing for years: whether you have declining efficacy, and whether that declining efficacy can lead to addiction," Gottlieb told the Washington Post in a Tuesday interview.
The FDA will require the makers of brand-name pharmaceuticals to fund independent, randomized and controlled research of the effects of long-term opioid use for pain relief, Gottlieb said. Generic opioid makers would be required to adapt their behavior based on the result of said investigations.
Such studies were not previously something the FDA could compel pharmaceutical firms to undertake, Gottlieb told the Post. Previously, the regulatory agency only had the power to order post-market studies of safety, as opposed to efficacy. But, under the SUPPORT Act, passed last October, the FDA now has the ability to require studies of the effectiveness of on-the-market drugs.
The idea that the safety and effectiveness of opioid drugs still needs to be studied may surprise some. After all, humans have used opioids in their organic form for millennia, and their narcotic and analgesic effects have long been well-known.
But this level of knowledge leaves open a number of questions. What is the effect of long-run prescription opioid usage on the risk of dependence and death? Are opioids always a more effective painkiller than OTC substitutes (e.g. acetaminophen), or are there times when a Tylenol prescription would be preferable?
Questions like these, about the effectiveness and risks of opioid use for chronic pain, are surprisingly under-studied. A 2015 systematic review of the literature identified zero English-language articles which compared opioids to non-opioids for chronic pain over a term of more than a year.
"Evidence is insufficient to determine the effectiveness of long-term opioid therapy for improving chronic pain and function," the authors conclude. "Evidence supports a dose-dependent risk for serious harms."
But this lack of evidence has not stopped doctors from prescribing — and pharmaceutical firms from pushing — billions of opioid pills to American chronic pain patients. There were 191 million opioid prescriptions dispensed in 2017, down from the 2012 high of 255 million, but still 58.7 prescriptions per 100 Americans. Prescription opioids were implicated in about 14,000 deaths in 2017, although that figure is likely to have fallen since.
The scientific basis for all of this prescribing, according to subsequent reporting, is usually traceable back to a single letter in the 1980 New England Journal of Medicine, which was subsequently misinterpreted to show that long-term opioid prescription for chronic pain carried no associated risks.
Gottlieb's requirement, if successfully imposed, would hopefully rectify the surfeit of evidence around opioid prescribing. What new studies will show about the potent analgesics' effects remains to be seen.