FDA pushback could put chronic kidney disease drug in jeopardy

Ardelyx reported this week that the FDA sent the company a letter saying that there are “deficiencies” in the application for its lead drug candidate.

Without much explanation, the agency said that it took issue with the “size of the treatment effect and clinical relevance” of the company’s new drug, tenapanor, which was developed to treat chronic kidney disease.

Ardelyx sent its application for the treatment in June and after responding with its letter, the FDA declined to meet with the company to hash out the implications of its critique. The agency did clarify that the drug has not been declined and is still under review.

News of the FDA rebuke sent shares for Ardelyx tumbling by about 74% this week. 

"This is an extremely disheartening and disappointing communication from the FDA, particularly following the weeks of label discussions that occurred in early April, the fact that our NDA submission included three pivotal trials across 1,000 patients, all of which met their primary and key secondary endpoints, as well as the additional data analyses we submitted in late April in response to the FDA's requests," Mike Raab, president, and chief executive officer of Ardelyx, said in a press release. "We plan to work with the FDA to learn more about the identified deficiencies and will seek to resolve them as quickly as possible."