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Ardelyx’s Tenapanor Hits Another Regulatory Stumbling Block On Label, Post-Marketing Commitments

 
• By Alaric DeArment

While not an outright rejection, the Deficiencies Preclude Discussion letter came as a surprise given the expectation of the drug’s approval for hyperphosphatemia in adults with chronic kidney disease on dialysis.

FDA stop sign. Sarah Silbiger/Getty Images
• Source: Sarah Silbiger/Getty Images

First came the delay in its regulatory action date. Now, Ardelyx Inc. has received a Deficiencies Preclude Discussion (DPD) letter from the US Food and Drug Administration stating that the agency has found stumbling blocks in the approval application for tenapanor, its drug to lower serum phosphorus in chronic kidney disease (CKD) patients on dialysis, despite the widespread view that the agency would approve the drug.

Ardelyx said 19 July that it received the letter from the FDA on 13 July, informing the company that the...

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US FDA To Advisory Committee Industry Reps: Don’t Talk Too Much

 
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Nonvoting industry representative’s presence at Pediatric Advisory Committee meeting was required by statute, the agency said, a de facto acknowledgement that an April directive precluding industry reps from sitting on advisory committees has had little practical effect.

Capricor Gets Complete Response For DMD Cell Therapy: Unconvincing Data Or New Attitude At FDA?

 
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EMA’s PRIME Scheme Explored: Growing Designations - But Are Accelerated Assessments Slipping?

 
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US FDA’s CRL Release More Incremental Than ‘Radical’ Transparency

 
• By Bridget Silverman

The transparency initiative collects CRLs already made public in approval packages on its drugs@fda site to post on the openFDA public portal.

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EMA’s PRIME Scheme Explored: Growing Designations - But Are Accelerated Assessments Slipping?

 
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While the first six months of the year saw eight new drugs targeting a range of diseases enter the European Medicines Agency’s priority medicines scheme, and three PRIME-designated treatments go on to win EU marketing approval, use of the accelerated assessment mechanism appears to be limited.

Global Pharma Guidance Tracker - June 2025

 
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Stay up to date on regulatory guidelines from around the world with the Pink Sheet’s Guidance Tracker. The complete Global Pharma Guidance Tracker, with sortable and searchable listings going back to 2014, is available online.

US FDA’s CRL Release More Incremental Than ‘Radical’ Transparency

 
• By Bridget Silverman

The transparency initiative collects CRLs already made public in approval packages on its drugs@fda site to post on the openFDA public portal.