Drugmaker AstraZeneca on Wednesday said that its experimental breast cancer treatment improved patient survival without the disease getting worse in a study, a positive outcome in the development of the therapy key to the company's pipeline.

The results showed statistically significant and clinically meaningful improvement in progression-free survival compared with the standard-of-care treatment, the company said.

The British drugmaker claimed study success in a first-line setting in breast cancer. Elsewhere, Rezdiffra sales continued to grow and a cancer biotech cut staff.

The phase 3 SERENA-6 study randomised patients with HR-positive, HER2-negative advanced breast cancer whose tumours had an emergent ESR1 mutation to receive either AZ’s candidate or an aromatase inhibitor (anastrozole or letrozole), both taken alongside a CDK4/6 inhibitor (palbociclib, ribociclib or abemaciclib).

In the Phase III SERENA-6 trial, camizestrant—in combination with CDK-inhibitors—beat out current standard-of-care treatments in terms of progression-free survival, according to AstraZeneca.

AstraZeneca announced on Wednesday that its drug candidate camizestrant demonstrated a statistically significant and clinically meaningful improvement in progression-free survival in the first-line treatment of hormone receptor-positive,

Bank of America (NYSE: BAC) analysts estimate a peak sales potential of $6 billion for camizestrant across the SERENA-6 and SERENA-4 trials. They note that SERENA-4 is a first-line (1L) trial requiring success in patients without ESR1 mutations, with data expected in the first half of 2026.

Pharmaceuticals major AstraZeneca said on Wednesday that its experimental treatment, camizestrant, improved survival in patients with an advanced form of breast cancer without the disease getting worse in a late-stage clinical trial.

AstraZeneca Plc’s experimental breast cancer pill helped patients live for longer without their disease worsening, the UK drugmaker said.