Fewer first cycle new drug approvals by the US Food and Drug Administration (FDA) could be the first evidence of a toughening regulatory environment, according to new research.
The report, entitled The US Approval Trends and Yearbook 2006-2007, shows that approval rates for standard new molecular entities (NME) and biologic license applications (BLA) have plummeted in the last two years, from 38 per cent in 2003 to only eight per cent last year.
"NMEs and BLAs represent an important subset of applications and it is the purest measure of the industry's new drug productivity," Mark Mathieu, author and editor of the report, told In-PharmaTechnologist.com.
"Lower approval rates for these types of applications shows that the FDA might be more conservative in its decision-making for the approval of new drugs."
There has been some anecdotal evidence and many claims of a toughening regulatory environment since the Vioxx withdrawal in 2004, but this could be the first evidence that support such claims until now.
What is more, there has been a two-year rise in first-cycle not-approvable actions on standard NME/BLAs, according to the report, published by Barnett Educational Services, a division of Parexel's Medical Communication Services.
The FDA's Centre for Drug Evaluation and Research (CDER), which reviews drug applications and monitors drugs once they are on the market, has issued not-approvable letters for 30 per cent of the standard NME/BLA applications submitted last year, an increase from five per cent in 2003.
Furthermore, the not-approvable rate for these types of new drugs is a seven-year high.
However, according to the research, in 2005, just over 70 per cent of priority NME and BLAs received first-cycle approval, a three-year high and the third highest level since the user-fee sytstem was implemented in 1992.
But, according to Mathieu, priority entities represent true advance and therefore the FDA is not likely to get more severe on these types of approvals.
"Applications for standard entities is the first place where the regulator becomes more conservative," he added.
"That is why, for priority NMEs, there is no evidence of tougher regulations."
Mathieu said there is no way of predicting how the regulatory environment will evolve for new drug approvals but if we look at previous events of the past, in a similar scenario, a fall in drug approvals usually lasts for a year.
The FDA has come under scrutiny last month after an independent report urged the regulator to implement large reforms to ensure the safety of new prescription drugs once they are on the market.
According to the report, released by the Institue of Medicine's (IOM) Committee, the core problem is that the FDA currently cannot ensure the safety of new prescription drugs because of inadequate funds, structural problems, and unclear and insufficient regulatory authorities.
The committee said that the FDA needs more budget and manpower to ensure it keeps its focus on the safety of the drugs it regulates, not only before approval, but also throughout the time they are on the market, and came up with a series of steps to improve safety review.