Plexxikon is pursuing a number of drug targets for the treatment of cardiovascular and renal disease, including polycystic kidney disease, hypertension and atherosclerosis.

Polycystic Kidney Disease

Plexxikon is developing PLX5568, a novel, oral kinase inhibitor for the treatment of polycystic kidney disease (PKD), and is completing a Phase 1 study. Preliminary data from the Phase 1 studies in healthy volunteers show that PLX5568 was well tolerated at all dose levels tested. Additionally, drug exposure levels in blood reached the initial target range for efficacy.

PLX5568 has demonstrated compelling efficacy in multiple preclinical models of PKD, a debilitating, genetic disease that leads to loss of kidney function. There is currently no treatment for PKD. This disease affects 600,000 patients in the U.S. and 12.5 million patients worldwide.

Hypertension

Plexxikon is utilizing its Scaffold-Based Drug Discovery Platform™ to identify non-peptidic inhibitors of renin, a validated drug target for hypertension. A number of scaffold candidates have been identified and very low-molecular weight leads are now in optimization.

Developing non-peptidic renin compounds with good oral availability has been a longstanding challenge for the industry. An advantage of Plexxikon's approach is the generally smaller size of Plexxikon's drug candidates, which often translates into more attractive pharmaceutical properties.