Chinook Acquires Global Rights to Develop Atrasentan for Alport, Other Kidney Diseases

Chinook Therapeutics acquired the global rights for the development and commercialization of AbbVie‘s atrasentan, an investigational compound for the treatment of people with primary glomerular kidney disease, including patients with Alport syndrome.

Chinook, a Canadian biotech focused on medicines for kidney diseases, expects to launch a Phase 3 clinical trial in the second half of 2020 to evaluate atrasentan’s effects in selected patients with rare primary glomerular diseases who are at high risk of progressively losing kidney function.

“This in-license of atrasentan provides a unique opportunity for Chinook to add a potential new drug to its precision medicine portfolio for the treatment of rare, severe chronic kidney diseases,” Eric Dobmeier, Chinook’s president and CEO, said in a press release.

“We have plans to advance the program into a clinical trial for primary glomerular disease patients who have few other treatment options, in addition to exploring other addressable patient populations,” he added.

Atrasentan is a blocker of the endothelin-A receptor, a protein found in the muscle tissue of blood vessels involved in vasoconstriction (the narrowing of the blood vessels through the contraction of their muscular wall). This receptor is activated in human primary glomerular diseases and can harm kidney function, causing protein in the urine (proteinuria), kidney inflammation, and scarring that contributes to progressive kidney function loss.

Atrasentan blocks the effect of endothelin-1 (ET-1), a small protein that normally binds the endothelin-A receptor to trigger vasoconstriction in order to regulate blood pressure (vasoconstriction increases blood pressure) and vascular tone (the degree of vessel constriction).

Elevated kidney ET-1 levels were recently found to be associated with a rapid progression of primary glomerular disease — which suggests that blocking the endothelin-A receptor could be a promising approach to treat these conditions, including Alport syndrome.

Currently, the management of primary glomerular diseases is largely limited to non-specific therapies that reduce blood pressure. Immunosuppressive agents can be added but this is normally insufficient and leads to side effects.

Atrasentan was discovered and initially developed by AbbVie. Last year, the company published results of SONAR (NCT01858532), a Phase 3 placebo-controlled trial of 3,600 patients with diabetic kidney disease. The trial demonstrated that adding atrasentan to standard therapy significantly reduces proteinuria and the risk of progression to end-stage renal disease, or kidney failure. Atrasentan also showed an acceptable safety profile that is suitable for long-term dosing.

According to Chinook, these data indicate that atrasentan can potentially preserve and protect kidney function in patients with severe kidney diseases.

With the new licensing agreement, Chinook obtains worldwide rights for all applications of atrasentan and assumes full responsibility for its development and commercialization, should the compound be approved.

In turn, AbbVie will gain an undisclosed upfront payment plus potential future milestones and royalties, and an equity stake in Chinook.