Ardelyx Regains Worldwide Development and Commercialization Rights for its Late-Stage Development Candidate, Tenapanor, and Related Portfolio of NHE3 Compounds

Ardelyx has entered into a termination agreement with AstraZeneca, such that all the rights to Ardelyx's portfolio of NHE3 inhibitors, including Ardelyx's lead product candidate, tenapanor, are returned to Ardelyx. Ardelyx has agreed to pay AstraZeneca $15 million upfront along with other future contingent payments. Concurrently, Ardelyx will pay an additional $10 million in R&D costs and for the acceleration of the transfer of the program back to Ardelyx. Ardelyx formed a partnership with AstraZeneca in October 2012 to develop and commercialize Ardelyx's internally discovered portfolio of NHE3 inhibitors including tenapanor.

With the acquisition of worldwide rights from AstraZeneca, Ardelyx plans to accelerate the clinical development path for tenapanor in constipation-predominant irritable bowel syndrome (IBS-C) by initiating a Phase 3 clinical program in IBS-C patients in the fourth quarter of this year. Additionally Ardelyx is planning to begin a Phase 2b clinical trial in the fourth quarter of this year to evaluate the optimal dosing regimen for tenapanor for the treatment of hyperphosphatemia in dialysis patients.

"By regaining the worldwide rights to tenapanor, we now have a late-stage clinical asset that has demonstrated significant promise for the treatment of IBS-C and hyperphosphatemia, both of which are conditions where we believe tenapanor could potentially transform the treatment paradigm," said Mike Raab, President and CEO.

"Ardelyx can now accelerate the clinical development of tenapanor to meet the needs of two underserved patient populations. We are grateful for the substantial investment that AstraZeneca has made in the NHE3 program, and we have been fortunate to have them as a partner," Mr Raab added.