Therapeutic Response Statement (Sensitivity)

This therapeutic response statement Supports the relationship that HER2-negative, PIK3CA oncogenic variants, and PR positive status confers therapeutic sensitivity to Fulvestrant, Inavolisib, Palbociclib in patients with Invasive Breast Carcinoma.

The U.S. Food and Drug Administration granted approval to palbociclib in combination with inavolisib and fulvestrant for the treatment of adult patients with endocrine-resistant, PIK3CA-mutated, hormone receptor-positive, HER2-negative, locally advanced or metastatic breast cancer, as detected by an FDA-authorized test, following recurrence on or after completing adjuvant endocrine therapy.

This statement is based on a regulatory approval from the Food and Drug Administration:

IBRANCE is a kinase inhibitor indicated in combination with inavolisib and fulvestrant for the treatment of adult patients with endocrine-resistant, PIK3CA-mutated, HR-positive, HER2-negative, locally advanced or metastatic breast cancer, as detected by an FDA-authorized test, following recurrence on or after completing adjuvant endocrine therapy.

Citation

Pfizer. Ibrance (palbociclib) [package insert]. U.S. Food and Drug Administration website. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/207103s024lbl.pdf. Revised June 2026. Accessed October 13, 2026. Pfizer, Inc. Ibrance (palbociclib) [package insert]. U.S. Food and Drug Administration website. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/207103s024lbl.pdf. Revised June 2026. Accessed October 6, 2026.

Contributions

Date	Contributor	Description
2026-10-13	Van Allen lab	Initial curation of this indication into moalmanac-db.
2026-06-24	Food and Drug Administration	Indication received traditional approval.