Concert Pharmaceuticals Announces Positive Results From Phase II Trial Of CTP-499 In Diabetic Kidney Disease

Concert Pharmaceuticals announced via press release that a Phase II clinical trial of CTP-499 has shown positive results. CTP-499, a selective PDE inhibitor, treats patients with diabetic kidney disease in an attempt to delay progression to end-stage renal failure.

Concert Pharmaceuticals and Dr. Bhupinder Singh, a clinical investigator and Medical Director of Apex Research of Riverside, presented the findings at the National Kidney Foundation 2014 Spring Clinical Meeting. Dr. Singh said, "The results of this Phase 2 trial after 48 weeks were highly encouraging and, I believe, support the progression of CTP-499 into larger clinical trials. Overall, these data suggest that CTP-499 may protect patients from suffering loss of kidney function by reducing the progression of fibrosis.”

CTP-499

CTP-499 is a selective PDE inhibitor that slows the progression of type 2 diabetic kidney disease in patients with macroalbuminuria. CTP-499 is an HDX analog and a pentoxifylline metabolite. Initial testing showed that CTP-499 slowed the negative processes in diabetic kidney disease. Concert is developing the agent as a complementary treatment along with the standard of care, angiotensin modulation with an ACEi or ARB.

Phase II Trial

The Phase 2 trial was a placebo-controlled, three-part trial in several centers. Part 1 evaluated the safety and efficacy of 600 mg CTP-499 twice daily for 24 weeks in 151 patients. Investigators measured the urinary albumin to creatinine ratio (UACR). Part 2 offered patients who completed Part 1 an option to continue receiving CTP-499 or a placebo for an additional 24 weeks. Part 3 offered the 123 patients who completed Part 2 the option to receive CTP-499 for up to 48 weeks. Part 3 is ongoing.

Investigators found that patients treated with CTP-499 showed a slower decline of kidney function at 48 weeks measured by the serum creatinine. Patients treated with CTP-499 had a mean increase in serum creatinine 0.13 mg/dL compared to 0.21 mg/dL in the placebo group — a 38 percent improvement. The primary endpoint of the trial was not met as measured by UACR (urinary albumin to creatinine ratio), a marker of kidney tissue damage. However, Concert suggests that longer term treatment may show better UACR measurements. Patients tolerated the treatment and only one adverse event occurred. Concert Pharmaceuticals will meet with the FDA to discuss Phase III trials.