AstraZeneca shares fall 5% on disappointing lung cancer drug trial results

AstraZeneca shares fell more than 5% Tuesday morning, the biggest one-day drop in seven months, after the British pharmaceutical giant announced disappointing lung cancer drug trial results.

The Covid-19 vaccine maker was trading at the bottom of the FTSE 100 and dragged the wider healthcare sector lower after data published Monday showed that its experimental drug datopotamab deruxtecan did not significantly improve overall survival results for patients.

Share were down 4.8% by 11:00 a.m. London time.

The late-stage trial results from the TROPION-Lung01 Phase III trial showed that the overall survival rate from the new drug "did not reach statistical significance," the company said.

The company's Dato-DXd drug was being trialled against chemotherapy treatment docetaxel on patients whose non-small cell lung cancer had returned after one or two previous treatment attempts.

Susan Galbraith, executive vice president of oncology R&D at AstraZeneca, said the results showed a "clinically meaningful" trends towards improving the survival rate of patients with advanced lung cancer.

The drug trials have been monitored by investors who hope that it could be another winning medication following the success of the Cambridge, England-based company's Covid-19 vaccine.

Earlier trials in July 2023 also disappointed markets despite showing some success in stalling cancer progression.

The drug, which is being developed with Japan's Daiichi Sankyo, is seeking approval from the U.S. Food and Drug Administration, which is due in December.

Citigroup said in a note that it has been a "mixed picture" for the drug but that confidence in the approval "remains high," even as Monday's results add complexity to the picture.

"We think the data create more complexity and thus if anything, further slightly raise approval risks short-term," the analysts wrote in the Monday note.