Atezolizumab for Alveolar Soft Part Sarcoma: A Clinical Trial Update

A Alice P. Chen (Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD) C Christina L. Rosenberger (Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD) N Nancy Moore (Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD) J Jared C. Foster (Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD) A Abdul Rafeh Naqash E Elad Sharon G Geraldine O'Sullivan Coyne (Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD) G Gary K. Schwartz (Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH) R Richard F. Riedel (avin Ratan, MD, MEd, Division of Cancer Medicine, Department of Sarcoma Medical Oncology, University of Texas, MD Anderson Cancer Center, Houston, TX; Bernd Kasper, MD, PhD, Sarcoma Unit, Mannheim University Medical Center, Mannheim Cancer Center, University of Heidelberg, Mannheim, Germany; Thierry Alcindor, MD, MS, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA; Patrick Schöffski, MD, Department of General Medical Oncology, University Hospitals Leuven, Leuven Cancer Institute, KU Leuven, Leuven, Belgium; Winette T. van der Graaf, MD, PhD, Department of Medical Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands; Noah Federman, MD, Departments of Pediatrics and Orthopedics, UCLA Jonsson Comprehensive Cancer Center, UCLA David Geffen School of Medicine, Los Angeles, CA; Nam Q. Bui, MD, Division of Oncology, Department of Medicine, Stanford University, Stanford, CA; Gina D'Amato, MD, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL; Richard...) J John Glod (Center for Cancer Research, National Cancer Institute, Bethesda, MD) J James S. Hu (Division of Oncology, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA) A Anthony P. Conley (The University of Texas MD Anderson Cancer Center, Houston, TX) W William L. Read (Emory University, Atlanta, GA) M Melissa A. Burgess (University of Pittsburgh Medical Center Hillman Cancer Center, Pittsburgh, PA) E Elizabeth J. Davis (Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN) P Priscilla Merriam (Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA) H Hari A. Deshpande (Department of Internal Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, CT) B Brian H. Ladle (Department of Oncology, Johns Hopkins University School of Medicine and Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD) S Scott H. Okuno (Mayo Clinic, Rochester, MN) J Jill C. Beck (Division of Pediatric Hematology-Oncology, University of Nebraska Medical Center, Omaha, NE) J James L. Chen K Katherine V. Ferry-Galow (Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD) K Kristin K. Fino (Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD) B Brandon L. Miller (Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD) D Deborah F. Wilsker (Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD) A Asma Begum (Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD) R Ralph E. Parchment J James H. Doroshow (Center for Cancer Research, National Cancer Institute, NIH)

Abstract

We previously reported initial results of the pivotal phase II trial of atezolizumab for patients with alveolar soft part sarcoma (ASPS; ClinicalTrials.gov identifier: NCT03141684 ). Here, we report on three additional years of observation. Fifty-three patients with ASPS received atezolizumab. Median duration of response increased to 37.0 months. Objective response rate (ORR) and median progression-free survival (mPFS) remained essentially as previously reported (35.8% [95% CI, 23.1 to 50.2] and 20.8 months [IQR, 7.6-not reached], respectively). ASPSCR1::TFE3 fusion type was determined for 47/53 patients; ORR and mPFS were higher among the 41 patients expressing type 1 (43.9% [95% CI, 28.5 to 60.2] and 28.3 months [IQR, 9.2-not reached], respectively) than the six patients expressing type 2 (0% [95% CI, 0 to 45.9] and 7.5 months [IQR, 3.9-not reached], respectively, PFS HR, 3.2 [95% CI, 1.01 to 10.2]). Eleven patients chose a per-protocol drug holiday (range, 3.5-26.4 months) after ≥2 years of treatment; two experienced disease progression during the holiday. Nine eligible patients elected to receive bevacizumab plus atezolizumab after progressing on monotherapy; ORR was 0% and mPFS was 18.5 months (IQR, 7.9-21.1) in this small cohort. Long-term results support using atezolizumab to treat ASPS, even for several years; a drug holiday with careful monitoring may be an option for some patients.

Article Details

Volume / Issue Vol. 44, Issue 16
Published June 01, 2026
Pages 1490-1497
ISSN 0732-183X
Publisher Lippincott Williams & Wilkins

Journal Info

Journal of Clinical Oncology

Lippincott Williams & Wilkins

ISSN: 0732-183X Health Sciences

Authors (28)

A

Alice P. Chen

Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD

C

Christina L. Rosenberger

Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD

N

Nancy Moore

Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD

J

Jared C. Foster

Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD

A

Abdul Rafeh Naqash

E

Elad Sharon

G

Geraldine O'Sullivan Coyne

Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, MD

G

Gary K. Schwartz

Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH

R

Richard F. Riedel

avin Ratan, MD, MEd, Division of Cancer Medicine, Department of Sarcoma Medical Oncology, University of Texas, MD Anderson Cancer Center, Houston, TX; Bernd Kasper, MD, PhD, Sarcoma Unit, Mannheim University Medical Center, Mannheim Cancer Center, University of Heidelberg, Mannheim, Germany; Thierry Alcindor, MD, MS, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA; Patrick Schöffski, MD, Department of General Medical Oncology, University Hospitals Leuven, Leuven Cancer Institute, KU Leuven, Leuven, Belgium; Winette T. van der Graaf, MD, PhD, Department of Medical Oncology, Netherlands Cancer Institute, Amsterdam, the Netherlands; Noah Federman, MD, Departments of Pediatrics and Orthopedics, UCLA Jonsson Comprehensive Cancer Center, UCLA David Geffen School of Medicine, Los Angeles, CA; Nam Q. Bui, MD, Division of Oncology, Department of Medicine, Stanford University, Stanford, CA; Gina D'Amato, MD, Sylvester Comprehensive Cancer Center, University of Miami Health System, Miami, FL; Richard...

J

John Glod

Center for Cancer Research, National Cancer Institute, Bethesda, MD

J

James S. Hu

Division of Oncology, University of Southern California Norris Comprehensive Cancer Center, Los Angeles, CA

A

Anthony P. Conley

The University of Texas MD Anderson Cancer Center, Houston, TX

W

William L. Read

Emory University, Atlanta, GA

M

Melissa A. Burgess

University of Pittsburgh Medical Center Hillman Cancer Center, Pittsburgh, PA

E

Elizabeth J. Davis

Division of Hematology/Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN

P

Priscilla Merriam

Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA

H

Hari A. Deshpande

Department of Internal Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, CT

B

Brian H. Ladle

Department of Oncology, Johns Hopkins University School of Medicine and Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD

S

Scott H. Okuno

Mayo Clinic, Rochester, MN

J

Jill C. Beck

Division of Pediatric Hematology-Oncology, University of Nebraska Medical Center, Omaha, NE

J

James L. Chen

K

Katherine V. Ferry-Galow

Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD

K

Kristin K. Fino

Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD

B

Brandon L. Miller

Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD

D

Deborah F. Wilsker

Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD

A

Asma Begum

Clinical Pharmacodynamics Biomarker Program, Applied/Developmental Research Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD

R

Ralph E. Parchment

J

James H. Doroshow

Center for Cancer Research, National Cancer Institute, NIH