Eyeing second Japanese approval, Daiichi and Exelixis announce positive pivotal for kidney drug
Nearly a year after earning regulatory approval against hypertension in Japan, Daiichi Sankyo announced new positive Phase III trial data that could push them and the drug they developed in collaboration with Exelixis toward approval for diabetic nephropathy.
Daiichi tested Minnebro (esaxerenone) in a double-blind trial against a placebo in 455 patients with diabetic nephropathy and on an angiotensin II blocker (ARB) or angiotensin converting enzyme (ACE) inhibitor. On the primary endpoint – microalbuminuria remission rate – Minnebro outpaced a placebo 22% to 4%. The Daiichi drug also reduced overall microalbuminuria-to-creatinine ratio by 58%, while it increased by 8.3% in the placebo.
Microalbuminuria, also known as moderately increased albuminuria, is an increase in the amount of albumin in urine and occurs when the kidneys leak an excess amount of the protein into urine. It is considered a sign of kidney disease.
Esaxerenone is a mineralocorticoid receptor blocker. The concern with such blockers is that they can increase hyperkalemia – increased blood potassium levels, a dangerous condition that can lead to heart attacks. Minnebro quadrupled the risk of hyperkalemia in the study, with 8.8% of the esaxerenone developing the condition against 2.2% of the placebo group, but the condition alleviated after the administration period.
Exelixis largely focuses on cancer, but the nearly 15-year-old collaboration with Daiichi has proved steadily lucrative in non-oncology areas. On top of a $20 million upfront payment and double-digit royalties just beginning to come through, the 25-year-old biotech earned $20 million when Daiichi filed for regulatory approval in 2018 and another $20 million when Daiichi sold its first dose of the drug. That’s on top of the $15 million milestone payout when the first Phase III on hypertension began in 2016.
Exelixis said it stands to earn further milestones on Minnebro. According to Daiichi’s Q3 report, diabetic nephropathy is the only other indication they are in “major” pursuit of with this drug.