A study published in the medical journal Heath Affairs implies that the US Food and Drug Administration (FDA) has been on the right track when taking forward promising pipeline drugs for expedited new drug application (NDA) review.
It examined 135 drugs that were approved between 1999 and 2012, and found that 76 of those selected for expedited approval have provided significantly stronger health gains than the others. This justifies the decision to speed up the approval of these drugs, despite often heavy criticism about this process.
Cutting through red tape
Because of the volume of clinical trial data to be sifted through, and the importance of making the right decision on whether to approve or reject marketing authorisation, it can take up to two years for the FDA to complete a review of a drug following Phase III clinical trials.
To address this, the FDA has developed a number of designations for drugs that they believe fill a strong unmet need in a serious disease, or offer a significant improvement over existing drugs.
Including accelerated approval and priority review, these initiatives either grant the drug a larger share of the FDA’s resources or allow approval based on less stringent criteria such as surrogate clinical trial markers.
They work well, and the average review time for a priority drug is less than half that of a standard review.
Shortage of evidence?
The difficulty lies in obtaining further data once a drug has reached the market.
A study published in May found that for more than 35% of drugs approved between 2005 and 2012 on the basis of a single pivotal trial or surrogate markers, no post-approval studies were conducted in the five and a half year period during which these drugs were followed up.
Because of the FDA’s increasing reliance on studies such as these, and their key role in speeding up the approval of expedited drugs, weaknesses in efficacy or potential safety risks may go unspotted. There have been several high-profile instances of drugs being removed from the market only a few years after approval following expedited approval.
The challenge for the FDA in the coming years will be to establish the right balance between the risks and benefits of speedy approvals.
Even so, given the fact that three quarters of drugs approved in 2016 qualified for at least one priority review programme, it is encouraging that the drugs being taken to the market most quickly appear to be the best choices.