Pharmaceutical Technology

Ardelyx wins FDA approval for phosphate absorption inhibitor

The company also secured $50m in debt financing to support the commercial launch of Xphozah in November.

The US Food and Drug Administration (FDA) approved Ardelyx’s Xphozah (tenapanor) as an add-on therapy for CKD patients on dialysis who are either intolerant of or have an inadequate response to phosphate binders.

Xphozah is a phosphate absorption inhibitor which reduces serum phosphorus levels by blocking its absorption. It is administered as an oral tablet twice a day. The drug’s path to approval has been a tumultuous one. In July 2021, the FDA rejected Xphozah’s new drug application (NDA). After a successful appeal, the company filed a new NDA in April 2023.

Alongside the approval, Ardelyx secured an additional $50m in debt financing from SLR Capital Partners to finance the launch of Xphozah, based on a 17 October press release. The funds will also be invested into the US commercialisation of the company’s irritable bowel with constipation therapy Ibsrela (tenapanor).

The US-based company entered the arrangement for interest-only funding with SLR in February 2022. The original agreement with SLR was for $50m in financing, $27.5 of which was withdrawn in February 2022. The remaining $22.5m is planned for withdrawal this month to fund the November 2023 launch of Xphozah, per the 17 October press release.

The current amendment allows for an additional $50m in funding to be drawn by 15 March 2024, with an option to borrow $50m in further financing. The interest-only period for the existing and new tranches has also been extended to 31 December 2026.

Ardelyx added that it is under no obligation to withdraw funds in the future. All the capital from the facility matures on 1 March 2027. The company’s market cap stands at $751.627m.

Xphozah’s approval was based on data from three Phase III clinical trials (NCT03427125, NCT02675998, and NCT03824587), based on a 17 October press release. The studies demonstrated Xphozah’s ability to decrease phosphorus levels both as a monotherapy and in combination with a phosphate binder.

Diarrhoea was the most common side effect associated with Xphozah. It occurred in 43%-53% of the patients and was mild to moderate in severity across the three trials. Severe diarrhoea was reported in 5% of the patients in all three trials.