The US Food and Drug Administration (FDA) on Wednesday released draft guidance to help biopharma companies address the precision of blood pressure measurements in the assessment of the effects of a drug in development.
The 11-page draft recommends “systemic characterization of the effect of a drug on blood pressure during drug development.”
While noting that nearly every drug development program has “some assessment of the effect of a drug on blood pressure, the methods for assessing blood pressure vary,” the guidance adds that “the precision of blood pressure measurement differs widely, such that small increases in blood pressure that could be relevant for the overall assessment of the risks of a drug may not be reliably detected in some drug development programs.”
Steve Nissen, chairman of cardiovascular medicine at the Cleveland Clinic, explained to Focus
in a phone interview that the draft is correct on the varying methods for assessing blood pressure, though he also noted that pharmacovigilance studies are “largely a joke” and “tend not to work.”
“There is no financial incentive to do safety trials, period,” he added. “They get done when FDA demands them.”
In terms of examples of drugs where higher blood pressure may be an issue, Nissen pointed to attention deficit-hyperactivity disorder (ADHD) drugs. “I’m particularly concerned about the ADHD drug problem – as they’re largely dangerous drugs and not understood to be dangerous,” he said.
Many adults over 55 are using them and raising their blood pressure with these drugs, he added, noting, “we don’t have good data” on the effects.
In 2006, Nissen was part of an FDA advisory committee that voted 8 to 7 to recommend a boxed warning describing the cardiovascular risks of stimulant drugs used to treat attention deficit-hyperactivity disorder (ADHD). Nissen, writing in an NEJM perspective
, called the decision “unexpected, largely because the FDA had not requested a review of current labeling for this class of drugs; it had merely asked for recommendations of approaches to studying the cardiovascular risks associated with these drugs."
In the draft guidance, FDA also recommends the use of Ambulatory Blood Pressure Measurement (ABPM) “as it provides the precision and accuracy needed to detect these smaller changes in blood pressure.”
Nissen concurred, noting that the magnitude of the effect can be seen with a relatively modest sample size, and "it's always good to have a placebo."
Assessment of Pressor Effects of Drugs Guidance for Industry