(Sharecast News) - AstraZeneca's 'Truqap', or capivasertib, in combination with 'Faslodex', or fulvestrant, has secured approval from the US Food and Drug Administration (FDA) for specific breast cancer treatments, the company announced on Friday.

The FTSE 100 pharmaceutical giant said the approval covered the treatment of adult patients with hormone receptor (HR)-positive, HER2-negative locally advanced or metastatic breast cancer exhibiting specific biomarker alterations (PIK3CA, AKT1, or PTEN).

Eligible patients must have experienced disease progression on at least one endocrine-based regimen in the metastatic setting or recurrence within 12 months of completing adjuvant therapy.

The firm said the FDA's decision to approve was based on the 'CAPItello-291' phase three trial results, as published in The New England Journal of Medicine earlier this year.

In the trial, the combination of Truqap and Faslodex demonstrated a 50% reduction in the risk of disease progression or death compared to Faslodex alone in patients with tumours bearing PI3K/AKT pathway biomarker alterations.

AstraZeneca said breast cancer remained the most prevalent cancer worldwide and a significant contributor to cancer-related mortality.

HR-positive breast cancer, accounting for over 65% of cases, is characterised by the expression of oestrogen or progesterone receptors and a HER2-low or HER2-negative status.

A substantial portion of patients - up to 50% - harbour mutations in PIK3CA, AKT1, or alterations in PTEN.

While endocrine therapies were commonly employed, resistance often developed to first-line cyclin-dependent kinase (CDK) 4/6 inhibitors and estrogen receptor-targeting therapies, emphasising the demand for additional endocrine therapy-based options.

The safety profile of Truqap plus Faslodex in the CAPItello-291 trial was consistent with previous evaluations of the combination.

At the same time as the drug's approval, the FDA also sanctioned a companion diagnostic test to identify relevant biomarker alterations.

The US regulatory submission received priority review status and was assessed under 'Project Orbis' - a collaborative framework for simultaneous submission and review of oncology medications among participating international partners.

In line with Project Orbis, regulatory authorities in Australia, Brazil, Canada, Israel, Singapore, Switzerland and the UK were also reviewing Truqap plus Faslodex.

Additionally, regulatory applications for Truqap in combination with Faslodex were under review in China, the European Union, Japan, and multiple other nations.

From a financial perspective, under their agreement, Astex Therapeutics would receive a milestone payment from AstraZeneca upon the drug's first commercial sale in the US, along with royalties on future sales.

"The rapid US approval of Truqap reinforces the important role of the PI3K/AKT pathway in HR-positive breast cancer and the critical need to test patients at the time of diagnosis, as up to 50% have tumours with these alterations," said Dave Fredrickson, executive vice-president of AstraZeneca's oncology business unit.

"As a first-in-class medicine, this approval provides a critical new option for patients in the US with this specific type of disease and we look forward to bringing Truqap to the many breast cancer patients who can benefit across the globe."

At 0838 GMT, shares in AstraZeneca were up 1.36% at 10,304p.

Reporting by Josh White for Sharecast.com.