A cancer drug being developed by AstraZeneca failed to "achieve statistical significance" in helping patients live longer than with chemotherapy in a phase 3 trial, the drugmaker said Monday.

AstraZeneca said on Monday its experimental precision drug developed with Japan's Daiichi Sankyo did not significantly improve overall survival for patients with a type of breast cancer in a late-stage trial.

AstraZeneca and Daiichi Sankyo’s TROP2-directed antibody-drug conjugate (ADC) has again failed to improve overall survival (OS) in a phase 3 trial. The latest miss happened in breast cancer, a setting in which Gilead’s rival Trodelvy significantly improved OS in a prior late-phase study.

A new AstraZeneca drug has failed to extend significantly the lives of breast cancer patients in a blow to the company’s ambitions to hit an $80bn revenue target by 2030.

AstraZeneca said on Monday its experimental precision drug developed with Daiichi Sankyo did not significantly improve overall survival for patients with a type of breast cancer in a late-stage trial.

AstraZeneca released results from the TROPION-Breast01 Phase 3 trial of datopotamab deruxtecan, showing no statistically significant improvement in overall survival. The trial met its progression-free survival endpoint,

AstraZeneca and Daiichi Sankyo have reported results from the TROPION-Breast01 Phase III clinical trial of datopotamab deruxtecan (Dato-DXd) for breast cancer. The trial compared Dato-DXd to the investigator's choice of chemotherapy in patients with inoperable or metastatic hormone receptor (HR)-positive, HER2-low or negative breast cancer.

It said the drug did not 'achieve statistical significance' in terms of the survival rates of those suffering from breast cancer compared to chemotherapy.

AstraZeneca stock slumped Monday after its Daiichi Sankyo-partnered drug missed its mark in a study of patients with breast cancer.