Neoadjuvant stereotactic radiotherapy and enfortumab vedotin: A phase I/II study for localized, cisplatin ineligible, muscle invasive bladder cancer (STAR-EV).

T Tian Zhang (Division of Hematology‐Oncology, Department of Internal Medicine University of Texas Southwestern Medical Center Dallas Texas USA) S Solomon L. Woldu (Department of Urology, UT Southwestern Medical Center, Dallas, TX) M Minjae Lee Q Qian Qin S Suzanne Cole (From the Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda (A.B.A., N.S., S.N., L.L., L.C.), the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore (J.H.-C.), and the Investigational Drug Branch, Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Rockville (H.S., E.S.) — all in Maryland; the Alliance Statistics and Data Management Center, Mayo Clinic, Rochester, MN (K.V.B., M.O., C.M., G.P.B.); AdventHealth Cancer Institute and the University of Central Florida, Orlando (G.S.); Dana–Farber/Harvard Cancer Center, Boston (S.B., B.M.); UNC Lineberger Comprehensive Cancer Center, Chapel Hill (W.Y.K.), and Duke University Medical Center and Duke Cancer Institute, Durham (J.H., S.H.) — both in North Carolina; the University of Kansas Cancer Center, Westwood (R.P.); Memorial Sloan Kettering Cancer Center, New York (M.Y.T., M.J.M., J.E.R.), and Roswell Park Comprehensive Cancer Center, Buffalo (G.C.) — both in...) W Waddah Arafat (Division of Hematology and Oncology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX) C Changchuan Jiang J Jue Wang (Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering) K Kevin Dale Courtney (Department of Internal Medicine, Division of Hematology and Oncology, UT Southwestern, Dallas, TX) A Andrew DeVilbiss (UT Southwestern Medical Center, Dallas, TX) M Molly McGuire R Raquibul Hannan (UT Southwestern Medical Center, Dallas, TX) D Daniel X. Yang (Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX) A Aurelie Garant (Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX) I Isamu Tachibana (Department of Urology, UT Southwestern Medical Center, Dallas, TX) K Kris Gaston (Department of Urology, UT Southwestern Medical Center, Dallas, TX) A Andrew Zhuang Wang (Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX) V Vitaly Margulis Y Yair Lotan (Department of Urology, UT Southwestern Medical Center, Dallas, TX) N Neil B. Desai (Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX)

Abstract

TPS4623 Background: Patients with muscle invasive bladder cancer (MIBC) may not be candidates for cisplatin-based chemotherapy based on their comorbidities and clinical status. Based on EV-103 cohort H, patients with localized, cisplatin ineligible MIBC respond well to enfortumab vedotin (EV), with 36% pathologic complete responses (pCRs). Radiation (XRT) is also an effective therapy for MIBC, with recent retrospective data showing safety when combining XRT-EV. Therefore, we designed a trial with EV and XRT to improve pCR rates. Methods: STAR-EV is a single center, phase 1/2 trial open at UT Southwestern Medical Center. Patients will receive EV 1.25mg/m2 IV days 1/8 every 3 weeks for 3 cycles, with either sequential or concurrent stereotactic body XRT (SBRT) in 5 fractions. The safety lead-in phase starts with SBRT given at cycle 3 day 21 and then escalated forward to start at cycle 2 day 15 (level 1) or cycle 1 day 15 (level 2). All patients undergo radical cystectomy (RC). Dose limiting toxicities during the safety portion include non-hematologic adverse events grade 3 or higher, not completing 3 cycles of EV, delaying SBRT over 2 weeks, or delaying RC over 8 weeks. Rate of pCR is the primary endpoint for efficacy, with a goal of 60% pCR. In a Simon’s two-stage design, if more than 3 pCRs are seen in the first 8 patients, 11 additional patients will be enrolled (total n = 19). The null hypothesis will be rejected if more than 10 pCRs are found. Main inclusion criteria include urothelial cancer of the bladder, cT2-4aN0M0, > 50% urothelial histology, and cisplatin ineligible; main exclusion criteria include any small cell/neuroendocrine histology, prior systemic therapy for bladder cancer, prior pelvic XRT, baseline grade 2 or higher neuropathy, prior allergic reaction attributed to EV, or uncontrolled intercurrent illness. Secondary endpoints include safety of combining EV and SBRT, rate of pathologic down-staging; and exploratory objectives include quality of life, disease free survival after RC, and delay of RC > 8 weeks from end of EV/SBRT. Serum and urinary biomarkers will be explored. The study is open and enrolling. Clinical trial information: NCT06394570 .

Article Details

Volume / Issue Vol. 43, Issue 16_suppl
Published June 01, 2025
ISSN 0732-183X
Publisher Lippincott Williams & Wilkins

Journal Info

Journal of Clinical Oncology

Lippincott Williams & Wilkins

ISSN: 0732-183X Health Sciences

Authors (20)

T

Tian Zhang

Division of Hematology‐Oncology, Department of Internal Medicine University of Texas Southwestern Medical Center Dallas Texas USA

S

Solomon L. Woldu

Department of Urology, UT Southwestern Medical Center, Dallas, TX

M

Minjae Lee

Q

Qian Qin

S

Suzanne Cole

From the Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda (A.B.A., N.S., S.N., L.L., L.C.), the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore (J.H.-C.), and the Investigational Drug Branch, Cancer Therapy Evaluation Program, National Cancer Institute, National Institutes of Health, Rockville (H.S., E.S.) — all in Maryland; the Alliance Statistics and Data Management Center, Mayo Clinic, Rochester, MN (K.V.B., M.O., C.M., G.P.B.); AdventHealth Cancer Institute and the University of Central Florida, Orlando (G.S.); Dana–Farber/Harvard Cancer Center, Boston (S.B., B.M.); UNC Lineberger Comprehensive Cancer Center, Chapel Hill (W.Y.K.), and Duke University Medical Center and Duke Cancer Institute, Durham (J.H., S.H.) — both in North Carolina; the University of Kansas Cancer Center, Westwood (R.P.); Memorial Sloan Kettering Cancer Center, New York (M.Y.T., M.J.M., J.E.R.), and Roswell Park Comprehensive Cancer Center, Buffalo (G.C.) — both in...

W

Waddah Arafat

Division of Hematology and Oncology, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX

C

Changchuan Jiang

J

Jue Wang

Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering

K

Kevin Dale Courtney

Department of Internal Medicine, Division of Hematology and Oncology, UT Southwestern, Dallas, TX

A

Andrew DeVilbiss

UT Southwestern Medical Center, Dallas, TX

M

Molly McGuire

R

Raquibul Hannan

UT Southwestern Medical Center, Dallas, TX

D

Daniel X. Yang

Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX

A

Aurelie Garant

Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX

I

Isamu Tachibana

Department of Urology, UT Southwestern Medical Center, Dallas, TX

K

Kris Gaston

Department of Urology, UT Southwestern Medical Center, Dallas, TX

A

Andrew Zhuang Wang

Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX

V

Vitaly Margulis

Y

Yair Lotan

Department of Urology, UT Southwestern Medical Center, Dallas, TX

N

Neil B. Desai

Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX