Posted 29 March 2017
By Michael Mezher
A team of officials from the US Food and Drug Administration (FDA) say that drugs approved following a priority review are three-and-a-half times more likely to receive a boxed warning after entering the market.
Unlike standard reviews, which can take up to ten months, drugs that treat serious conditions or offer a significant improvement over existing treatments can qualify for a shorter, six-month review.
However, the authors note that because drugs given priority review are intended to treat more serious conditions, "a greater degree of inherent risk is medically acceptable."
The officials, who include Gerald Dal Pan, director of the agency's Office of Surveillance and Epidemiology, also found that drugs approved with an initial boxed warning are nearly four times more likely to receive subsequent boxed warnings down the road.
The research, published in a recent study appearing in Drug Safety, sought to determine if certain quantifiable premarket data could be used to predict whether a drug would go on to receive a boxed warning or be withdrawn for safety reasons after being approved.
To conduct the study, the authors looked at more than 200 new small molecule drugs submitted to FDA since November 1997 and launched prior to 2010. According to the authors, 11 of these drugs were eventually withdrawn for safety reasons and 30 went on to receive postmarket boxed warnings.
However, the authors found that they were unable to use easily quantifiable data, such as clinical trial sample size or how close to the review goal date a drug was approved to predict either outcome.
As a result, the authors conclude that postmarket boxed warnings and withdrawals for safety reasons "are not discernable during a pre-market review and therefore might not be avoidable using current review data."