Ardelyx, Inc. (NASDAQ: ARDX), a clinical-stage biopharmaceutical company focused on cardio-renal, gastrointestinal and metabolic diseases, today announced that it has entered into a termination agreement with AstraZeneca (LSE: AZN, SSE: AZN, NYSE: AZN), 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 Chief Executive Officer.
"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.
In a separate press release, Ardelyx announced today a new product candidate, RDX022, for which it will be pursuing a 505b(2) regulatory pathway in the United States. Ardelyx is developing RDX022 for the treatment of elevated potassium, or hyperkalemia. Ardelyx expects to initiate clinical trials with RDX022 in mid-2015. Ardelyx also announced today that it has entered into an agreement to sell shares of common stock and warrants to purchase common stock for the aggregate gross proceeds of approximately $77.8 million in a private placement. Proceeds from the private placement will be used to develop both tenapanor and RDX022, two wholly-owned programs that are targeted to begin Phase 3 clinical trials in the fourth quarter 2015 and second half of 2016, respectively.