AstraZeneca’s $1.3 billion bet on CinCor Pharma and its mid-phase hypertension drug baxdrostat seems to have paid off based on a phase 3 readout.
The Big Pharma had been evaluating the aldosterone synthase inhibitor in a late-stage study of 796 patients with uncontrolled hypertension who received either 1 mg or 2 mg daily doses of baxdrostat, or placebo, for 12 weeks. These patients demonstrated a statistically significant and clinically meaningful reduction in their mean seated systolic blood pressure (SBP), hitting the trial’s primary endpoint, AstraZeneca announced Monday morning.
Baxdrostat was “generally well tolerated with a favourable safety profile,” according to AstraZeneca, which said it had been assessing the drug's long-term safety over the course of a year.
The U.K.-based Big Pharma didn’t drill into the details, instead holding back the data for the European Society of Cardiology Congress next month.
The study also showed that baxdrostat met its secondary endpoints, such as a reduction in SBP among a subgroup of patients with resistant hypertension, as well as the proportion of patients who achieved a seated SBP of under 130 mmHg at week 12.
Baxdrostat—which CinCor in-licensed from Roche before the biotech was then acquired by AstraZeneca in January 2023—is designed to lower levels of aldosterone, a hormone that regulates blood pressure, without affecting cortisol synthesis. Selectivity for CYP11B2, the gene that encodes aldosterone synthase, over CYP11B1, a gene involved in cortisol synthesis, is needed if drugs that treat cardiovascular diseases by lowering aldosterone levels are to succeed.
“We are very excited with the BaxHTN Phase III results, which show statistically significant and clinically meaningful reductions in systolic blood pressure,” Sharon Barr, EVP of BioPharmaceuticals R&D at AstraZeneca, said in a July 14 release.
“These findings provide compelling evidence of baxdrostat’s potential to address a critical unmet need by targeting aldosterone dysregulation, bringing a novel mechanism to a field that has seen little innovation in over two decades,” Barr added.
The $1.3 billion upfront payment that AstraZeneca handed over for CinCor looked like something of a gamble at the time, coming just weeks after baxdrostat missed the key endpoint of a phase 2 trial. But AstraZeneca—who it later transpired had been keeping an eye on baxdrostat for a while—used the failed trial to secure significantly improved terms for the acquisition.
AstraZeneca is also testing baxdrostat in phase 3 trials as a monotherapy for primary aldosteronism as well as in combination with the company’s blockbuster Farxiga in chronic kidney disease.