What do doctors know about FDA drug approval standards and the breakthrough therapy designation? Less than we’d hope.

By Dalia Deak

A study published this week in JAMA examined how much physicians know about FDA approval standards for new drugs and the breakthrough therapy designation. The investigators found major gaps in understanding with regard to both issues, despite intuitive beliefs to the contrary.

For the study, Kesselheim et al. conducted a national survey of board-certified internists and specialists. They selected a random sample of 300 clinically active internists and 900 specialists in endocrinology, hematology, and infectious diseases from the American Board of Internal Medicine’s diplomate list. Of the 1,148 physicians contacted, 692 physicians, or 60%, responded.

On the topic of FDA drug approval standards, the investigators posed the following three true/false or multiple-choice questions (shown below with the correct answers bolded):

• FDA approval typically means that a drug is as effective as other drugs approved to treat the same condition

True

False

• FDA approval typically means that a drug has benefits that outweigh its harms

True

False

• In order for a drug to get FDA approval it has to have…

A statistically significant result

A clinically important result

Both results

Neither of the results

A large majority of physicians, 73%, scored 33% or less. This finding is concerning given that our system of FDA approval and physician prescribing relies on an assumption of the “learned intermediary.” The learned intermediary rule allows for a pharmaceutical manufacturer to fulfill their duty to warn consumers by providing accurate and adequate warning to the prescribing physician. However, if physicians have important gaps in their basic understanding of what FDA approval actually means, their ability to effectively convey risk-benefit trade-offs may be hindered.

Physicians also by and large had a poor grasp of the breakthrough designation, generally overstating the demonstrated efficacy of breakthrough products. Over 75% of survey respondents incorrectly answered the question, “When the FDA calls a drug a breakthrough, does that mean that there is high-quality evidence that the drug is more effective than currently approved treatments?” with “Yes.” Furthermore, when presented with a hypothetical scenario asking them to choose between an “FDA-designated breakthrough drug” and “a drug with early promising study results but [that] has not been shown to improve survival or disease-related symptoms”—the very definition of a breakthrough drug—physicians overwhelmingly (94%) chose the FDA-designated breakthrough drug.

With 76 drugs designated as breakthrough as of April 2015, these findings raise concern over the impact of use the term. For example, a recent study showed that the terms “breakthrough” and “promising” increased consumers’ beliefs in a drug’s effectiveness and strength of supporting evidence. This links to broader issues raised in the use of language—particularly superlatives—in describing drugs.

Limitations of the study are important to keep in mind. The study’s authors note that their results are limited by social desirability and other inherent survey response biases as well as that the results may not be generalizable beyond internists and medical specialists. Yet, these findings may still be sufficiently troubling, particularly if the misconceptions identified contribute to physicians to overprescribing newly approved drugs and inadequately communicating how well these drugs work to their patients, as the study’s authors mention.