Itovebi (Inavolisib) for Breast Cancer

Overview
Itovebi is approved by the U.S. Food and Drug Administration (FDA) for use in combination with palbociclib and fulvestrant to treat adults with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced, or metastatic breast cancer. A person’s cancer must have a mutation (variation) in the PIK3CA gene, and the treatment is indicated for individuals whose cancer has recurred or progressed after adjuvant endocrine therapy (postsurgical hormone therapy). The PIK3CA mutation must be confirmed using an FDA-approved test. Itovebi is also known by its drug name, inavolisib.

Itovebi belongs to a class of drugs called kinase inhibitors. It works by blocking the activity of certain enzymes (kinases) that promote cancer cell growth, specifically targeting the mutated PIK3CA gene in breast cancer cells. By inhibiting these enzymes, the drug helps slow or stop the growth of the cancer. Itovebi is used in combination with palbociclib and fulvestrant to enhance treatment. Palbociclib is a cyclin-dependent kinase (CDK) inhibitor that prevents cancer cells from dividing and multiplying, while fulvestrant is an estrogen receptor (ER) antagonist that blocks the effects of estrogen on breast cancer cells. Together, these drugs help slow the progression of HR-positive, HER2-negative breast cancer.

How do I take it?
Prescribing information states that Itovebi is taken orally once daily, with or without food. It is usually combined with palbociclib and fulvestrant. The treatment should be taken exactly as prescribed by a health care provider. Dosing may need to be modified based on individual reactions, including side effects or specific medical conditions such as renal (kidney) impairment.

Side effects
Common side effects of Itovebi include decreased neutrophils (a type of white blood cell), decreased hemoglobin (a protein in red blood cells), increased fasting glucose, decreased platelets, decreased lymphocytes (another type of white blood cell), stomatitis (mouth sores), diarrhea, decreased calcium levels, fatigue, decreased potassium levels, increased creatinine (a waste product in blood), increased ALT (a liver enzyme), nausea, decreased sodium levels, decreased magnesium levels, rash, decreased appetite, COVID-19 infection, and headache.

Rare but serious side effects may include severe hyperglycemia (high blood sugar), stomatitis requiring corticosteroid mouthwash, and severe diarrhea that may lead to dehydration and kidney injury. Itovebi may also pose a risk to unborn infants.

For more information about this treatment, visit:

Itovebi (Inavolisib) Tablets, for Oral Use — U.S. Food and Drug Administration 

Itovebi — Drugs.com