Concert commences dosing in CTP-499 Phase 2 clinical trial for diabetic nephropathy

Concert Pharmaceuticals, Inc. today announced the initiation of dosing in a Phase 2 clinical trial evaluating CTP-499, an investigational drug for the treatment of diabetic nephropathy, the leading cause of chronic kidney disease (CKD) in the US. CTP-499 is intended to be additive to the current standard of care, angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) therapy, to prevent or slow progression of kidney damage in diabetic nephropathy and other types of chronic kidney disease.

"Kidney disease represents a major health concern, driven by higher rates of diabetes, obesity and an aging population. Despite available treatments, many patients progress to renal failure. The current pipeline for novel treatments is limited, and there is a need for more effective pharmacologic intervention to manage CKD and to slow disease progression. CTP-499 provides a new mechanism of action that has the potential to address this substantial unmet medical need," said James Shipley, M.D., Chief Medical Officer of Concert Pharmaceuticals.

The Phase 2 clinical trial is a randomized, double-blind, placebo-controlled, multi-center clinical trial to evaluate the safety and efficacy of CTP-499 in patients with type 2 diabetes and mild to moderate (stage 2/3) chronic kidney disease who demonstrate a loss of albumin into their urine. Such patients have an elevated risk for progression to end-stage renal disease as well as cardiovascular morbidity such as heart attack and stroke. Approximately 170 patients will be enrolled in the study. Following a stabilization period, patients will receive placebo or 600 mg of CTP-499 twice daily for 24 weeks. The primary endpoint is change in urine albumin to creatinine ratio (UACR) from pre-treatment baseline to post-treatment. Additional information about the Phase 2 clinical trial is available at www.clinicaltrials.gov.

In 2011, Concert completed four Phase 1 clinical trials with CTP-499, including a multiple dose safety and tolerability study in patients with CKD, supporting selection of the patient dosing regimen of 600 mg BID for the Phase 2 study. CTP-499 was generally well-tolerated with the most common adverse event being mild, transient nausea. Concert expects to present findings from its safety and tolerability study in CKD patients in 2012.

CTP-499 is an analog of 1-((S)-5-hydroxyhexyl)-3,7-dimethylxanthine (HDX), an active metabolite of pentoxifylline. CTP-499, a potential first-in-class treatment for diabetic nephropathy, possesses a pleiotropic mechanism of action with anti-inflammatory, anti-oxidant and anti-fibrotic properties. Its unique qualities may enable it to intervene in the pathophysiology of diabetic nephropathy, other forms of kidney disease and fibrotic indications. CTP-499 was developed using Concert's DCE Platform™ to provide a new chemical entity with an improved pharmacokinetic profile compared to pentoxifylline. CTP-499 incorporates deuterium in selected positions in the molecule, which improves the metabolic stability of the compound.