Parag Roy: A New Targeted Option for PIK3CA Wild-Type HR+/HER2- Metastatic Breast Cancer
Parag Roy/LinkedIn

Parag Roy: A New Targeted Option for PIK3CA Wild-Type HR+/HER2- Metastatic Breast Cancer

Parag Roy, Medical Oncologist at Tata Main Hospital shared a post on LinkedIn:

“FDA Approval Alert | A New Targeted Option for PIK3CA Wild-Type HR+/HER2- Metastatic Breast Cancer

The FDA has approved gedatolisib (Revtorpyk®) in combination with fulvestrant, with or without palbociclib, for patients with HR-positive, HER2-negative locally advanced or metastatic breast cancer without a PIK3CA mutation, following progression on endocrine therapy.

This approval marks an important milestone, as it expands targeted treatment options for the majority of patients with HR+/HER2− metastatic breast cancer who are PIK3CA wild-type.

What makes gedatolisib different?

Gedatolisib is a first-in-class intravenous dual PI3K/mTOR inhibitor, targeting both:

  • Class I PI3K
  • mTORC1 and mTORC2

Unlike earlier PI3K inhibitors, its activity is not dependent on PIK3CA mutations, enabling broader applicability while providing comprehensive inhibition of the PI3K/AKT/mTOR signaling pathway.

VIKTORIA-1 Trial Highlights

Study Design

  • Phase III, randomized, open-label
  • 392 patients with HR+/HER2− advanced/metastatic breast cancer
  • PIK3CA wild-type disease
  • Progression after endocrine therapy

Treatment Arms

  • Gedatolisib + Fulvestrant + Palbociclib
  • Gedatolisib + Fulvestrant
  • Fulvestrant alone

Key Results

Triple combination

  • Median PFS: 9.3 vs 2.0 months
  • HR 0.24
  • 76% reduction in the risk of progression or death

Double combination

  • Median PFS: 7.4 vs 2.0 months
  • HR 0.33
  • 67% reduction in risk

Objective Response Rate

  • 32% (triple therapy)
  • 28% (double therapy)
  • 1% (fulvestrant alone)

Overall survival data remain immature.

Safety Profile

The most common clinically relevant adverse events include:

  • Stomatitis
  • Dermatologic toxicities
  • Hyperglycemia
  • Embryo-fetal toxicity

Clinical Perspective

This approval addresses a long-standing unmet need for patients with PIK3CA wild-type endocrine-resistant HR+/HER2- metastatic breast cancer. The impressive improvement in progression-free survival reinforces the importance of continued targeting of the PI3K/mTOR pathway beyond endocrine resistance and introduces a new precision medicine strategy for a broader patient population.

It will be interesting to see how gedatolisib is integrated into future treatment algorithms and sequencing strategies alongside CDK4/6 inhibitors and emerging endocrine therapies.

What are your thoughts on where gedatolisib will fit into the evolving treatment landscape of HR+/HER2- metastatic breast cancer?”

Parag Roy