---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-22-032662"
form_type: "8-K"
ticker: "ARDX"
cik: "0001437402"
company_name: "ARDELYX, INC."
filed_at: "2022-12-29T23:59:59+00:00"
generated_at: "2026-06-20T21:52:03.657929+00:00"
event_type: "regulatory"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Ardelyx receives FDA appeal grant for XPHOZAH; plans NDA resubmission in H1 2023

## Summary
- On Dec 27, 2022, FDA OND granted appeal of July 2021 CRL for XPHOZAH (tenapanor) after Nov 16 CRDAC favorable vote.
- OND directs Division of Cardiology and Nephrology to work with Ardelyx on label development for hyperphosphatemia insufficiently managed on binder therapy.
- Company expects to resubmit NDA in H1 2023; review classification (Class 1: 2 months, Class 2: 6 months) to be determined post-resubmission.
- This reverses prior complete response letter and represents a major regulatory milestone for Ardelyx's only late-stage candidate.

## SEC filing metadata
- accession: 0001628280-22-032662
- form_type: 8-K
- ticker: ARDX
- cik: 0001437402
- company_name: ARDELYX, INC.
- filed_at: 2022-12-29T23:59:59+00:00
- event_type: regulatory
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1437402/000162828022032662/0001628280-22-032662-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1437402/000162828022032662/ardx-20221227.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-22-032662
- JSON: https://secwatch.observer/filing/0001628280-22-032662.json
- Plain text: https://secwatch.observer/filing/0001628280-22-032662.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.