A new analysis of 510(k) premarket review timeframes by the US Food and Drug Administration cites response times from companies to additional information requests as the key causes of review delays.

Overall, the FDA study found that between 2001 and 2010, percentages of 510(k) submissions that prompted Additional Information (AI) requests increased steadily and substantially—from 38% in 2001 to 77% in 2010. Average 510(k) decision time frames during that same period followed a similar trajectory, particularly from 2005 onward: In 2001, 510(k) decisions took an average of 102 days to reach, and in 2010 that average increased to 140 days. (These numbers track closely to a recent analysis of 510(k) clearance timeframes conducted by Emergo.)

The FDA ran two separate analyses of Additional Information (AI) letters. The first analysis, Cohort 1, examined quality of incoming submissions; the second, Cohort 2, examined factors behind the growing number of 510(k) review cycles. The agency found that 83% of Cohort 1 submissions as well as 82% of Cohort 2 submissions exhibited at least one quality deficiency.

In Cohort 1, more than half of all 100 submissions examined were found to contain inadequate device descriptions—by far the biggest factor prompting AI letters from the agency. Other common Cohort 1 submission deficiencies included indications for use (26%), failure to follow current guidance (24%) and general discrepancies throughout submissions (22%).

Among the 98 Cohort 2 submissions analyzed, FDA examiners found that roughly 60% of submissions had failed to follow guidance documents or recognized standards; nearly half of all submissions also contained inadequate device descriptions, and roughly 40% of Cohort 2 submissions lacked proper indications for use.

According to the study, the FDA received 4,103 510(k) submissions in 2009 and 3,880 in 2010. At least one AI letter was issued for 72% of 2009 submissions and 77% of 2010 submissions. Furthermore, 66% of second AI letters were issued because sponsors did not adequately address problems raised by their first AI letters.

Although the study minces no words in terms of blaming inadequate sponsor submissions as the key cause of 510(k) review delays, it also identifies ways in which the FDA could improve its own practices. Acknowledging industry complaints that AI letters sometimes request information that was not initially required at the start of 510(k) review processes, study examiners found that in the Cohort 1 category, AI letters asked for data that had not been previously requested in 12% of cases, and that eight percent—two-thirds—of those requests were inappropriate. In the Cohort 2 category, reviewers requested additional data not previously required in four percent of cases, two percent of which were found to be inappropriate.

Those percentages are not insignificant, but pale in comparison to the percentages of faulty 510(k) submissions as reported by the FDA. The question is, have medical device sponsors become more careless with their submissions over the course of the last 10 years, or have regulatory requirements become more complex and, perhaps, less transparent?