It is hardly a secret that the FDA is failing to keep up with deadlines for reviewing drugs, and the agency continues to say that inadequate staffing is to blame. In fact, here is a recent list of a dozen missed deadlines.

And more people are starting to keep track. For instance, Corey Davis, an analyst at Natixis Bleichroeder, counts at least 15 drugs so far this year where decisions were not made on time, which leaves companies and investors “hanging,” because “ambiguity breeds weakness” in drugmakers’ stock prices, he tells Bloomberg News. “To keep the companies and investors in limbo is completely unprecedented on this scale,” Davis says. “I’m sure there but have been some, but I can’t think of even one high-profile PDUFA date that got ignored last year.”

The FDA sets non-binding timelines for action on new medicines under the Prescription Drug User Fee Act, known as PDUFA, the law under which drugmakers help pay the agency to handle their applications. “We do continue to treat PDUFA goal dates as something that we take very seriously, and we’re trying to meet them,” John Jenkins, head of the FDA’s Office of New Drugs, tells Bloomberg. “But we haven’t been able to meet all of them for various reasons this year.”

Drug-safety legislation approved by Congress last year gave the FDA new responsibilities, adding to the workload of a staff that was already too small to keep up, Jenkins continues. The FDA couldn’t say how many action dates it missed last year. Davis and other analysts tell Bloomberg they didn’t compile last year’s data either.

Among the drugs delayed by the FDA include Promacta, a bleeding-disorder drug from Glaxo and Ligand Pharmaceuticals, and the diabetes drug alogliptin, from Takeda Pharmaceutical. In a statement this month, Takeda said the FDA didn’t complete its review of alogliptin as expected by October 27 “due to internal resource constraints.”

The agency’s goal is to review and act within 10 months on 90 percent of standard new drug applications and within 6 months on priority applications for drugs that offer major advances or provide a treatment where no adequate therapy is available.

Increases in user fees paid by drugmakers, and other funding, have allowed the FDA to hire more. The agency’s Office of New Drugs hired about 200 people in the fiscal year ended in September and expects to soon reach 890 full-time employees, an FDA spokeswoman writes to Bloomberg in an e-mail.

“While we have hired extensively this year, there is a long, steep learning curve for new review staff so we can’t expect that their arrival will immediately translate into improvement in the impact of workload,” she wrote. And Jenkins adds that, once the new employees are in place and trained, the number of missed deadlines should decrease.

Drugmakers understand the FDA’s difficulties and are hoping the issues are resolved quickly, says Alan Goldhammer, vp for scientific and regulatory affairs for PhRMA.

Missing target dates “has a huge impact” on patients, said Kevin Cain, assistant vp for government affairs and programs for the National Health Council, which represents patient advocacy groups, drugmakers and other health interest organizations. “Any missed dates are a bad thing for the people that we represent because that slows drugs in the pipeline,” Cain tells Bloomberg.

Groups that are critical of the FDA’s drug safety record have complained in recent years that the agency rushes to meet its goals for approving new med even when there are potentially dangerous side effects. Taking more time is “a good development,” Sidney Wolfe of Public Citizen, tells Bloomberg. “It’s starting to erode this arbitrary PDUFA deadline game in which medical officers there are forced to conclusions they might not fully agree with.”

The tally of missed action dates doesn’t include cases where the FDA formally extended review times or issued so-called complete-response letters, Bloomberg writes, adding that the letters inform drugmakers of reasons a product didn’t win approval, often requesting further data or additional studies.