New pill shows promise for Hard-to-Treat breast cancer in early trial

NCT ID NCT05683418

First seen May 14, 2026 · Last updated May 14, 2026

Summary

This study tests a new daily pill called TOS-358 in women with a specific type of advanced breast cancer (HR+ HER2-) that has a PIK3CA gene change. The main goals are to find the best dose and see if it is safe when taken alone or with standard treatments. About 241 adults will take part in this early-phase trial.

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This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.

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Contacts and locations

Study contacts

  • Contact

    Phone: •••-•••-•••• Email: •••••@•••••

Locations

  • Beth Israel Deaconess Medical Center

    RECRUITING

    Boston, Massachusetts, 02215, United States

    Contact Email: •••••@•••••

    Contact

    Contact Phone: •••-•••-•••• Email: •••••@•••••

  • Clinica Universidad de Navarra

    RECRUITING

    Pamplona, 31008, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • Comprehensive Cancer Centers of Nevada

    RECRUITING

    Las Vegas, Nevada, 89169, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact Email: •••••@•••••

    Contact

  • Dana-Farber Cancer Institute

    RECRUITING

    Boston, Massachusetts, 02215, United States

    Contact Email: •••••@•••••

    Contact

  • Hospital Clinico San Carlos

    RECRUITING

    Madrid, 28040, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • Hospital Clinico Universitario de Valencia

    RECRUITING

    Valencia, 46010, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • Instituto de Investigacion Oncologica Vall dHebron (VHIO) - EPON

    RECRUITING

    Barcelona, 08035, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • NEXT Oncology - Hospital Quironsalud Barcelona - PPDS

    RECRUITING

    Barcelona, 08023, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • NEXT Oncology - Hospital Quironsalud Madrid - PPDS

    RECRUITING

    Pozuelo de Alarcón, 28223, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • Northwestern Memorial Hospital

    RECRUITING

    Chicago, Illinois, 60611, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • START Barcelona HM Nou Delfos

    RECRUITING

    Barcelona, 08023, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • START MADRID Hospital Universitario Fundacion Jimenez Diaz - EDOS

    RECRUITING

    Madrid, 28050, Spain

    Contact

    Contact Phone: •••-•••-•••• Email: •••••@•••••

  • START MADRID Hospital Universitario HM Sanchinarro - CIOCC

    RECRUITING

    Madrid, 28050, Spain

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • Sarah Cannon Cancer Center

    RECRUITING

    Nashville, Tennessee, 37203, United States

    Contact

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact Phone: •••-•••-•••• Email: •••••@•••••

  • Texas Oncology - Flower Mound

    RECRUITING

    Flower Mound, Texas, 75028, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

  • University of Pennsylvania

    RECRUITING

    Philadelphia, Pennsylvania, 19106, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

    Contact Email: •••••@•••••

  • Vanderbilt-Ingram Cancer Center

    RECRUITING

    Nashville, Tennessee, 37232, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact

    Contact

  • Virginia Cancer Specialists

    RECRUITING

    Fairfax, Virginia, 22031, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

    Contact Phone: •••-•••-•••• Email: •••••@•••••

Conditions

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