(Adds details on trial results from paragraph 2 onwards)
Investing.com — shares tumbled as much as 9% on Wednesday, putting the stock on track for its steepest one-day decline in years, after the drugmaker said its experimental medicine Wainua failed to deliver the expected benefit in a key late-stage trial.
The study showed that adding Wainua to current standard treatment did not significantly reduce the risk of death or major cardiovascular complications in patients with a progressive heart disease, disappointing investors who had expected the trial to succeed.
The London-listed stock was the biggest drag on the in early trade as investors reassessed the drug’s commercial potential. The broader benchmark fell marginally by 0.4%.
Morgan Stanley described the result as a “meaningful downside surprise,” saying most investors had expected the trial to meet its primary goal despite questions over how much additional benefit the drug could provide on top of existing therapies.
The brokerage said consensus forecasts currently assume roughly $3.3 billion in risk-adjusted peak annual sales for Wainua in the heart disease indication and expects those estimates to be revised materially lower following the trial outcome, potentially leading to a mid-single-digit percentage cut to longer-term earnings expectations.
Morgan Stanley maintained its Overweight rating and 16,500 pence price target on AstraZeneca but said investor attention will now shift to several other late-stage pipeline catalysts due in the second half of 2026, including lung cancer candidate Dato-DXd, chronic obstructive pulmonary disease drug tozorakimab and breast cancer therapy camizestrant.
AstraZeneca and partner Ionis Pharmaceuticals Inc (NASDAQ:IONS) said detailed results from the study will be presented at the European Society of Cardiology Congress in August after further analysis of the full dataset.