FDA Approves Gedatolisib for HR+/HER2- Advanced Breast Cancer: What Nurses Need to Know

The FDA has approved gedatolisib (Revtorpyk) in combination with fulvestrant, with or without palbociclib, for adults with hormone receptor (HR)-positive, HER2-negative locally advanced or metastatic breast cancer.

This approval specifically targets patients without a PIK3CA mutation whose disease progressed after at least one line of endocrine therapy.

Clinical background and efficacy

The approval is based on the Phase 3 VIKTORIA-1 trial, which demonstrated a statistically significant improvement in progression-free survival (PFS). Patients receiving the "triplet" (gedatolisib, fulvestrant, and palbociclib) achieved a median PFS of 9.3 months, while those on the "doublet" (gedatolisib and fulvestrant) reached 7.4 months. In contrast, patients receiving fulvestrant alone saw a median PFS of 2.0 months.

Gedatolisib is a highly differentiated, multi-target inhibitor of the PI3K/AKT/mTOR (PAM) pathway. Unlike single-target inhibitors, it blockades all four Class I PI3K isoforms and mTORC1/2, minimizing the adaptive cross-activation that often leads to treatment resistance.

Nursing considerations: Dosing and administration

Gedatolisib is administered as an intravenous infusion (180 mg) over 30 minutes. The schedule follows a 28-day cycle: once weekly on Days 1, 8, and 15, followed by one week off. Oncology nurses should note that this IV administration differs from the oral regimens of other PAM pathway inhibitors, potentially allowing for closer clinical observation.

Managing adverse events

The safety profile includes warnings for stomatitis, neutropenia, and hyperglycemia.

According to Sara A. Hurvitz, MD, FACP, Senior Vice President of the Clinical Research Division at Fred Hutch Cancer Center, stomatitis is a primary concern for nursing management.

“I think it's important regardless what PAM inhibitor is being used that you advise them stomatitis can occur and so educate them on how to do the oral steroid mouthwash and on good oral care,” Hurvitz stated in an interview.

She noted that while approximately 60% of patients experienced some grade of stomatitis, grade 3 events occurred in only about 5% of those on the doublet.

For nurses, proactive education is vital. Hurvitz recommends:

• Early monitoring: “Given that stomatitis seems to be an early event that happens, I think we need early monitoring and checking in with patients in the especially first two cycles of therapy.”
• Dietary adjustments: Advise patients to avoid alcohol-based mouthwashes, rough foods, and extreme temperatures.
• Preventative measures: Suggesting ice chips during infusion — similar to protocols for IV chemotherapy — may help avoid mucositis.

The role of nursing outreach

The shift to weekly IV therapy facilitates more frequent contact between the patient and the care team. Hurvitz emphasized that any patient going on a PI3 kinase inhibitor requires frequent touch points with nursing. This includes phone calls and intentional outreach to patients to monitor GI tolerability, rash, and blood sugar.

By fostering these close connections, oncology nurses can enable safer, more effective care through early dose reductions or therapy holds when necessary.

References

1. FDA approves gedatolisib with fulvestrant, with or without palbociclib, for HR-positive, HER2-negative locally advanced or metastatic breast cancer. U.S. Food and Drug Administration. Published July 14, 2026. Accessed July 14, 2026.
2. Celcuity Announces FDA Acceptance of New Drug Application for Gedatolisib in HR+/HER2-/PIK3CA Wild-Type Advanced Breast Cancer. GlobeNewswire. Published January 20, 2026. Accessed July 14, 2026.
3. Hurvitz SA, Layman RM, Curigliano G, et al. VIKTORIA-1 Trial of Gedatolisib Plus Fulvestrant With or Without Palbociclib in Hormone Receptor–Positive/HER2–/PIK3CA Wild-Type Advanced Breast Cancer. J Clin Oncol. 2026;44(suppl):1-30. doi:10.1200/JCO-25-02643