ProKidney halts one CKD cell therapy phase 3 trial considered surplus to FDA approval

ProKidney has stopped one of a pair of phase 3 trials for its cell therapy for kidney disease after deciding it wasn’t essential for securing FDA approval.

The product, called rilparencel or REACT, is an autologous cell therapy creating by identifying progenitor cells in a patient’s biopsy. A team formulates the progenitor cells for injection into the kidney, where the hope is that they integrate into the damaged tissue and restore the function of the organ.

The North Carolina-based biotech has been running two phase 3 trials of rilparencel in Type 2 diabetes and chronic kidney disease: the REGEN-006 (PROACT 1) study within the U.S. and the REGEN-016 (PROACT 2) study in other countries.

The company has recently “completed a comprehensive internal and external review, including engaging with ex-FDA officials and seasoned regulatory experts, to decide the optimal path to bring rilparencel to patients in the U.S.”

Rilparencel received the FDA’s regenerative medicine advanced therapy (RMAT) designation back in 2021, which is designed to speed up the development and review process for regenerative medicines. ProKidney’s review concluded that the RMAT tag means rilparencel is eligible for FDA approval under an expedited pathway based on a successful readout of its U.S.-focused phase 3 trial REGEN-006.

As a result, the company will discontinue the REGEN-016 study, freeing up around $150 million to $175 million in cash that will help the biotech fund its plans into the early months of 2027. ProKidney may still need a top-up at some point, however, as on current estimates the remaining phase 3 trial may not read out top-line results until the third quarter of that year.

ProKidney, which was founded by Royalty Pharma CEO Pablo Legorreta, closed a $140 million underwritten public offering and concurrent registered direct offering in June, which had already extending the biotech’s cash runway into mid-2026.

“We decided to prioritize PROACT 1 to accelerate potential U.S. registration and commercial launch,” CEO Bruce Culleton, M.D., explained in this morning’s release.

“We are confident that this strategic shift in our phase 3 program is the most expeditious and resource efficient approach to bring rilparencel to market in the U.S., our highest priority market.”

The phase 3 trials were on pause during the early part of this year while ProKidney amended the PROACT 1 protocol as well as its manufacturing capabilities to meet international standards. Manufacturing of rilparencel and the trials themselves resumed in the second quarter.