A new three-drug treatment has been shown to help people with a common type of advanced breast cancer live longer. In the clinical study, adding the targeted therapy inavolisib (Itovebi) to palbociclib (Ibrance) and fulvestrant (Faslodex) extended life for people with PIK3CA-mutated, hormone receptor (HR)-positive, HER2-negative advanced breast cancer.

Each drug in this combination plays a different role:

• Approved by the U.S. Food and Drug Administration (FDA) in October 2024, inavolisib is a targeted therapy designed to block the effects of the PIK3CA mutation, which can drive cancer growth.
• Palbociclib is a CDK4/6 inhibitor that slows cancer cell division.
• Fulvestrant is a hormone therapy that blocks estrogen receptors, helping to stop cancer cells from using estrogen to grow.

Together, these drugs work to slow the cancer’s progression and extend survival.

The late-stage clinical trial included 325 participants who had not received prior treatment for metastatic disease. They were randomly assigned to receive either the three-drug combination or the standard two-drug regimen of palbociclib and fulvestrant. The median overall survival was 34 months with the inavolisib combination, compared to 27 months without it. The treatment more than doubled the time people lived without their cancer progressing (17.2 versus 7.3 months) and delayed the need for chemotherapy by about two years.

Learn more about life-extending treatments for metastatic breast cancer.

Expanding Treatment Options

This combination therapy may offer new hope to the roughly 40 percent of people with HR-positive breast cancer who have the PIK3CA mutation — a genetic change linked to worse outcomes and resistance to standard hormone therapy. By targeting this mutation, inavolisib may help extend survival and improve quality of life.

If you’re navigating treatment decisions, talk to your doctor about whether genetic testing or newer therapies might be appropriate for your type of breast cancer.

Find Your Team

On MyBCTeam, the social network for people living with breast cancer and their loved ones, members come together to ask questions, give advice, and share their stories with others who understand life with breast cancer.

Have you or a loved one been tested for the PIK3CA mutation? What treatments have helped you manage HR-positive breast cancer? Share your experiences in a comment below, start a conversation on your Activities page, or connect with like-minded members in Groups.