AlloCure Stem Cell Trial Provides Glimpse of Promising Treatment for Kidney Damage
Ever since nephrologist Robert Brenner joined Burlington, MA-based AlloCure in 2010, he’s been eager to find out how the company’s experimental stem-cell treatment for acute kidney injury would perform in people. Last week, he got his first hint of the answer—and it was a positive one.
On Nov. 12, AlloCure presented results from a Phase 1 study of its treatment at Kidney Week 2011, the annual meeting of the American Society of Nephrology, held in Philadelphia. There were 16 patients in the trial, and it was mostly designed to test the safety of the cells, which are found in adult bone marrow. But AlloCure also used the trial as an opportunity to measure efficacy, by comparing how the patients fared after the treatment to so-called historical controls—people who had suffered from acute kidney injury (AKI) in the past but not been given the cell treatment.
The risk of acute kidney injury, also known as AKI or acute renal failure, is particularly high in patients undergoing coronary bypass surgery or heart-valve surgery. All 16 patients in the trial who received AlloCure’s stem cell treatment, called AC607, were undergoing heart surgery and deemed to be at high risk of developing AKI. But only two of them developed AKI, amounting to 12.5 percent of the total patient universe. By contrast, 29.7 percent of the historical controls developed AKI.
AlloCure also looked at length of stay in the hospital, as well as readmission rates. Patients who got AC607 had a mean length-of-stay of 6.5 days, versus the non-treated patients,who had to stay for 9.3 days. The hospital readmission rate for patients who got the cells was 6.3 percent, versus 12.5 percent for the control group. “These results really provide everything we were hoping to see,” Brenner says. “We’re extremely motivated to move forward to Phase 2.” He says the Phase 2 trial will start sometime in the first half of 2012.
Here’s how AC607 works: AlloCure first isolates cells called mesenchymal stem cells (MSCs) from donated bone marrow, ensuring that the cells don’t carry “antigens,” which are surface markers that can provoke severe immune reactions. The company then grows the cells, which can be stored frozen, then quickly thawed and given to any patient—regardless of whether that patient is a bone-marrow match to the original donor. Physicians can identify patients at high risk for developing AKI by testing their blood for rising levels of a chemical called creatinine. “We envision our cells being available at hospitals throughout the country,” Brenner says. “It’s a short process to thaw them and prepare them for administration.”
Brenner and his colleagues at AlloCure, which moved to the Boston area from Salt Lake City in 2010, are well aware of the challenges involved in getting stem-cell treatments through the regulatory process. Several companies have tested adult stem cells in a range of diseases, with limited success. Most recently, on November 14, Menlo Park, CA-based Geron abandoned its heralded but bumpy efforts to develop treatments based on embryonic stem cells.
But none of that can dampen Brenner’s enthusiasm. “There’s been data [on adult stem cells] in conditions like heart failure that shows promise,” he says. “And we’re quite confident in the robustness of our process.”
Brenner has also been encouraged by a spate of deals around MSCs and kidney treatments. Last December, Frazer, PA-based Cephalon paid $220 million for a stake in the Aussie company Mesoblast, which is working on adult stem cell treatments for heart and nervous-system disorders. A few months before that, Abbott formed a $450 million deal with Irving, TX-based Reata Pharmaceuticals to develop a drug for chronic kidney disease. “All of this is very encouraging and shows enthusiasm for renal disease and MSCs as opportunities,” Brenner says.
He hopes that enthusiasm will serve AlloCure well in its ongoing efforts to raise capital to fund the next set of trials of AC607. The company raised $14.5 million in July 2008 from SV Life Sciences and the venture arm of Denmark-based drug giant Novo Nordisk. Brenner says the company is now “in the middle of” completing a Series B financing and hopes to lock that up “in a month or two.”
As someone who’s seen the burden kidney injury can present for patients, Brenner is particularly excited to move AlloCure’s development plan for AC607 forward. “It’s estimated that as many as 2 million patients in the U.S. develop acute kidney injury every year, often with profound consequences,” he says. “If patients lose a lot of kidney function, they have to be supported with dialysis, and at times that can be permanent. It’s extremely motivating to work on something that’s novel and promising for patients.”