June 18 (Reuters) - AstraZeneca said on Tuesday its breast cancer drug, Truqap, in combination with chemotherapy agent, paclitaxel, did not meet its main goals in a late-stage trial to improve overall survival of patients with a type of breast cancer.

Triple-negative breast cancer remains one of the most challenging forms of disease to treat due to the lack of known actionable biomarker targets, and chemotherapy-based regimens continue to be the mainstay of treatment, AstraZeneca said.

The trial, known as CAPItello-290, was testing whether the drug combination improved overall survival in patients with inoperable or metastatic triple-negative breast cancer versus the older and cheaper chemotherapy agent, paclitaxel, in combination with a placebo.

The study failed to achieve its goals in both the overall trial population and in a sub-group of patients with tumours harbouring specific biomarker alterations, the drugmaker said.

"While we are disappointed in the CAPItello-290 outcome, these results will further our understanding of the role of the PI3K/AKT pathway in breast cancer," said Susan Galbraith, executive vice president, oncology R&D, AstraZeneca.

(Reporting by Yadarisa Shabong in Bengaluru; Editing by Sherry Jacob-Phillips)