Back in May, the US Food and Drug Administration (FDA) denied a six-month extension of market exclusivity for Amgen's blockbuster Sensipar (cinacalcet), resulting in lawsuit filed by the drugmaker. A JAMA viewpoint published Wednesday argues that a decision in Amgen's favor could end up diminishing FDA's ability to encourage clinically meaningful pediatric studies.

The case centers on the interpretation of how companies "fairly respond" to FDA's written requests to conduct certain pediatric studies. In this instance, FDA and Amgen agreed on a written request encompassing four studies, though Amgen only completed three and failed to study the minimum number of patients for the minimum duration on the fourth.

According to the viewpoint, co-authored by members of Yale Law School's Collaboration for Research Integrity and Transparency, Amgen is not contesting FDA over the inconclusive safety data, but whether the studies responding to FDA's request is a "purely legal judgment" that involves "ministerial check-offs, not scientific decisions."

The viewpoint authors contend that a decision in favor of Amgen could end up undermining FDA's authority as "Amgen's interpretation creates disincentives for rigorous pediatric research. It would allow companies to simply select a number of criteria to fulfill, instead of conducting studies in a way that is likely to meet the FDA's standards for useful clinical evidence."

The authors added: "Courts should give deference to the FDA's current policy, which links 'fairly respond' to the studies' scientific value and allows the FDA to effectuate the purpose of the pediatric exclusivity program."

Co-author Jeanie Kim of Yale Law School told Focus via email: "The greater significance of this case is the implication for FDA's regulatory authority to administer the pediatric exclusivity program and interpret the statutory standard of 'fairly respond.'"

She also noted that if FDA wins in the pediatric exclusivity case, generic versions of Sensipar could hit the market as early as March 2018, "as long as they don't infringe on the later-issued patent covering the rapid-dissolution formulation."

Pediatric Exclusivity and Regulatory Authority: Implications of Amgen v HHS