Under construction – not a live service
Sign in
Taking peoplePhase 3

Tests inavolisib with Phesgo in HER2-positive, PIK3CA-mutated advanced breast cancer

Tests inavolisib plus Phesgo as maintenance in adults with HER2-positive, PIK3CA-mutated advanced breast cancer.

Key facts

Who runs it
Hoffmann-La Roche
Where
Singapore, SingaporeSee the 4 sitesAlso in 28 other countries, 195 sites
Registry title
A Study to Evaluate the Efficacy and Safety of Inavolisib in Combination With Phesgo Versus Placebo in Combination With Phesgo in Participants With PIK3CA-Mutated HER2-Positive Locally Advanced or Metastatic Breast Cancer
Status
Recruiting
Phase
Phase 3
People taking part
230 people, planned
Started
8 Sept 2023
Expected to end
28 Dec 2032
Type of study
Interventional, 3 groupsOne group gets an existing treatment, for comparison.
Treatments tested
  • Inavolisib
  • Phesgo
  • Placebo
  • Taxane-based Chemotherapy
  • Optional Endocrine Therapy of Investigator's Choice
Record updated
16 October 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults with HER2-positive breast cancer that has a PIK3CA gene change and has spread or cannot be removed by surgery. They have not had earlier drug treatment for this advanced disease.

Age
18 years or older
Sex
All sexes can join
Disease stage
Breast cancer (adenocarcinoma) that has spread or is locally advanced and cannot be cured by surgery. ECOG performance status 0 or 1.
Earlier treatment
No earlier non-hormonal cancer treatment for advanced HER2-positive disease before the first treatment phase of the study. No earlier PI3K, AKT or mTOR inhibitor for advanced disease. At least 6 months between the end of earlier non-hormonal treatment after or before surgery and the cancer coming back.
Biomarker or test result
Tumor test shows HER2-positive and a PIK3CA mutation. LVEF of at least 50% on a heart scan.

Main reasons for not taking part

  • Cancer got worse within 6 months of HER2-targeted therapy
  • Type 1 diabetes, or type 2 diabetes needing ongoing drug treatment
  • Inflammatory bowel disease
  • Active hepatitis B infection or serious liver disease
  • Lung disease with symptoms, such as pneumonitis or interstitial lung disease

The registry criteria, word for word

Show all 19 criteriaShow less

Who can take part

  • Eastern Cooperative Oncology Group (ECOG) Performance Status 0 or 1
  • Histologically or cytologically confirmed and documented adenocarcinoma of the breast with metastatic or locally advanced disease not amenable to curative resection
  • Confirmation of HER2 biomarker eligibility based on valid results from central testing of tumor tissue documenting HER2-positivity
  • Confirmation of PIK3CA-mutation biomarker eligibility based on valid results from central testing of tumor tissue documenting PIK3CA-mutated tumor status
  • Disease-free interval from completion of adjuvant or neoadjuvant systemic non-hormonal treatment to recurrence of >= 6 months
  • LVEF (left ventricular ejection fraction) of at least 50% measured by echocardiogram (ECHO) or multiple-gated acquisition scan (MUGA)
  • Adequate hematologic and organ function prior to initiation of study treatment

Who cannot take part

  • Prior treatment in the locally advanced or metastatic setting with any PI3K, AKT, or mTOR inhibitor or any agent whose mechanism of action is to inhibit the PI3K-AKT-mTOR pathway
  • Any prior systemic non-hormonal anti-cancer therapy for locally advanced or metastatic HER2-positive breast cancer prior to initiation of induction therapy
  • Disease progression within 6 months of receiving any HER2-targeted therapy
  • Serious infection requiring IV antibiotics within 7 days prior to Day 1 of Cycle 1
  • Any concurrent ocular or intraocular condition that, in the opinion of the investigator, would require medical or surgical intervention during the study period to prevent or treat vision loss that might result from that condition
  • History or active inflammatory bowel disease
  • Type 2 diabetes requiring ongoing systemic treatment at the time of study entry; or any history of Type 1 diabetes
  • Participants with active HBV infection
  • Clinically significant and active liver disease, including severe liver impairment, viral or other hepatitis, current alcohol abuse, or cirrhosis
  • Symptomatic active lung disease, including pneumonitis or interstitial lung disease
  • Any history of leptomeningeal disease or carcinomatous meningitis
  • Active inflammatory or infectious conditions in either eye or history of idiopathic or autoimmune-associated uveitis in either eye

Where in Singapore

Also in 28 other countries, 195 sites

  • Icon Cancer Centre Farrer ParkSingapore, SingaporeNo longer taking part
  • National Cancer CentreSingapore, SingaporeNo longer taking part
  • National University HospitalSingapore, SingaporeNo longer taking part
  • Tan Tock Seng HospitalSingapore, SingaporeNo longer taking part

About the trial

What the trial wants to find out

This study will evaluate the efficacy and safety of inavolisib in combination with Phesgo (pertuzumab, trastuzumab, and rHuPH20 injection for subcutaneous use) compared with placebo in combination with Phesgo, as maintenance therapy, after induction therapy in participants with previously untreated HER2-positive advanced breast cancer (ABC).

The 3 groups in the trial

  • Induction Therapy: Phesgo plus Taxane-Based ChemotherapyOther group

    Participants will be administered the treatments as outlined in the interventions section.

    Treatment: Phesgo and Taxane-based Chemotherapy

  • Maintenance Therapy: Inavolisib plus PhesgoTreatment being tested

    Participants will be administered the treatments as outlined in the interventions section.

    Treatment: Inavolisib, Phesgo, and Optional Endocrine Therapy of Investigator's Choice

  • Maintenance Therapy: Placebo plus PhesgoExisting treatment, for comparison

    Participants will be administered the treatments as outlined in the interventions section.

    Treatment: Phesgo, Placebo, and Optional Endocrine Therapy of Investigator's Choice

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov and on the EU's official list of trials (CTIS).
Official title
A Phase III, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Efficacy and Safety of Inavolisib in Combination With Phesgo Versus Placebo in Combination With Phesgo As Maintenance Therapy After First Line Induction Therapy in Participants With PIK3CA-Mutated HER2-Positive Locally Advanced or Metastatic Breast Cancer
Plain-language title
Tests inavolisib with Phesgo in HER2-positive, PIK3CA-mutated advanced breast cancerGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 12 November 2026.
Record updated
16 October 2026