Pfizer’s IBRANCE® in Combination with Standard-of-Care Therapies Extends Median Progression-Free Survival by Over 15 Months in Phase III PATINA Study

Pfizer and Alliance Foundation Trials, LLC (AFT) have announced groundbreaking results from the Phase III PATINA trial, demonstrating that the addition of IBRANCE® (palbociclib) to first-line maintenance therapy in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (MBC) significantly improves progression-free survival (PFS). These findings, presented at the 47th San Antonio Breast Cancer Symposium (SABCS), reveal that IBRANCE, when combined with anti-HER2 and endocrine therapies, extends median PFS by over 15 months.

Key Findings from the PATINA Trial:

The Phase 3 PATINA study (NCT02947685) investigated IBRANCE in combination with standard anti-HER2 therapy (trastuzumab or trastuzumab plus pertuzumab) and endocrine therapy, following induction chemotherapy. The trial involved 518 patients with HR+, HER2+ metastatic breast cancer. Key results include:

Median Progression-Free Survival (PFS): Patients treated with IBRANCE showed a median PFS of 44.3 months, compared to 29.1 months for those receiving standard-of-care therapy without IBRANCE. This represents a significant improvement of over 15 months (HR: 0.74; p = 0.0074).

Safety Profile: IBRANCE was well-tolerated, with no new safety signals identified. The most common adverse events included neutropenia, leukopenia, fatigue, and diarrhea, which were generally mild to moderate in severity.

Looking Ahead: The Future of IBRANCE in HER2+ MBC

These encouraging results make IBRANCE the first CDK4/6 inhibitor to demonstrate clinical benefit in a Phase III trial in first-line HR+, HER2+ metastatic breast cancer. While IBRANCE is not yet indicated for HER2+ disease, these findings underscore its potential as a maintenance treatment in combination with standard therapies. Pfizer is committed to discussing these results with regulatory authorities as it seeks to expand the clinical applications of IBRANCE in breast cancer treatment.

About the PATINA Trial

The PATINA trial is a randomized, open-label Phase III study designed to evaluate the efficacy and safety of IBRANCE combined with anti-HER2 therapy and endocrine therapy in HR+, HER2+ metastatic breast cancer. It is sponsored by AFT in collaboration with international cancer research groups. The trial's primary endpoint was progression-free survival (PFS), with overall survival (OS) as a secondary endpoint.

About IBRANCE® (palbociclib)

IBRANCE is an oral CDK4/6 inhibitor that regulates the cell cycle, and is currently approved in over 108 countries for HR+, HER2- advanced or metastatic breast cancer in combination with endocrine therapy. The results from the PATINA trial may pave the way for its use in HR+, HER2+ metastatic breast cancer, offering a potential new treatment option for this patient population.

Safety and Important Information:

The safety profile of IBRANCE in the PATINA study was consistent with its established safety data. However, the most common adverse events include neutropenia, leukopenia, and fatigue. As with all CDK4/6 inhibitors, there are risks of severe neutropenia and interstitial lung disease/pneumonitis, which should be closely monitored during treatment.

Looking Ahead: A Commitment to Innovation in Breast Cancer Treatment

The positive results from the PATINA study represent a significant milestone in the treatment of HR+, HER2+ metastatic breast cancer, and Pfizer remains focused on addressing the unmet needs of patients with breast cancer worldwide.