Disappointing lung cancer drug trial results cause AstraZeneca's shares to fall 5%.

• After announcing disappointing lung cancer drug trial results, AstraZeneca experienced their largest one-day drop in seven months.
• The experimental drug did not significantly improve overall survival results for patients, as shown in data published Monday.
• The healthcare sector was dragged lower by the Covid-19 vaccine maker, which was trading at the bottom of the FTSE 100.

On Tuesday morning, the British pharmaceutical giant experienced a significant decline in shares, with a one-day drop of over 5%, marking the largest drop in seven months. This was due to the announcement of disappointing results from a lung cancer drug trial.

The healthcare sector was dragged lower on the FTSE 100 after the Covid-19 vaccine maker's experimental drug datopotamab deruxtecan failed to significantly improve overall survival results for patients.

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

The TROPION-Lung01 Phase III trial did not show a statistically significant overall survival rate for the new drug, according to the company.

Patients with non-small cell lung cancer who had failed one or two previous treatments were being tested with the company's Dato-DXd drug against chemotherapy treatment docetaxel.

AstraZeneca's executive vice president of oncology R&D, Susan Galbraith, stated that the results indicated a "clinically significant" trend towards enhancing the survival rate of patients with advanced lung cancer.

The investors are closely monitoring the drug trials, hoping that it will be another successful medication after the success of the company's Covid-19 vaccine from Cambridge, England.

Despite showing some success in stalling cancer progression, earlier trials in July 2023 also failed to meet market expectations.

The drug, developed in collaboration with Daiichi Sankyo, is awaiting approval from the U.S. Food and Drug Administration, which is expected to be granted in December.

Despite Monday's results, Citigroup stated in a note that confidence in the drug's approval remains high, and the situation has been a "mixed picture."

The analysts wrote in their Monday note that they believe the data adds complexity, which may slightly increase approval risks in the short term.