Phase II Study of Enzalutamide for Patients With Androgen Receptor-Positive Salivary Gland Cancers (Alliance A091404)

Alan L. Ho, Nathan R. Foster, Alex J. Zoroufy, Jordan D. Campbell, Francis Worden, Katharine Price, Douglas Adkins, Daniel W. Bowles, Hyunseok Kang, Barbara Burtness, Eric Sherman, Roscoe Morton, Luc G.T. Morris, Zaineb Nadeem, Nora Katabi, Pamela Munster, Gary K. Schwartz

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

PURPOSE The androgen receptor (AR) is expressed (+) in a subset of salivary gland cancers (SGCs). This phase II trial evaluated the efficacy of the antiandrogen enzalutamide in AR+ SGC.METHODSPatients with locally advanced/unresectable or metastatic AR+ SGCs were enrolled. Enzalutamide (160 mg) was given orally once daily. The primary end point was the best overall response rate per RECIST v1.1 within eight cycles. Confirmed responses in ≥ 5 of 41 patients would be considered promising. Secondary end points were progression-free survival, overall survival, and safety.RESULTS Forty-six patients were enrolled; 30 (65.2%) received prior systemic therapy, including 13 (28.3%) with AR-targeted drugs. Of seven (15.2%) partial responses (PRs), only two (4.3%) were confirmed per protocol and counted toward the primary end point. Twenty-four patients (52.2%) had stable disease; 15 (32.6%) had progression of disease as best response. Twenty-six patients (56.5%) experienced tumor regression in target lesions; 18 (39.1%) had partial response/stable disease ≥ 6 months. Tumor regressions were observed in female patients (5 of 6 [83.3%]) and those who received prior AR- (6 of 13 [46.2%]) or human epidermal growth factor receptor 2-targeted therapies (5 of 8 [62.5%]). Three patients remained on treatment at data cutoff (duration, 32.2-49.8 months). The median progression-free survival was 5.6 months (95% CI, 3.7 to 7.5); the median overall survival was 17.0 months (95% CI, 11.8 to 30.0). The most common adverse events were fatigue, hypertension, hot flashes, and weight loss. Total and free testosterone levels increased by a mean of 61.2% and 48.8%, respectively, after enzalutamide. CONCLUSION Enzalutamide demonstrated limited activity in AR+ SGC, failing to meet protocol-defined success in part because of a lack of response durability. Strategies to enhance the efficacy of antiandrogen therapy are needed.

Original languageEnglish
Pages (from-to)4240-4249
Number of pages10
JournalJournal of Clinical Oncology
Volume40
Issue number36
DOIs
StatePublished - Dec 20 2022

Fingerprint

Dive into the research topics of 'Phase II Study of Enzalutamide for Patients With Androgen Receptor-Positive Salivary Gland Cancers (Alliance A091404)'. Together they form a unique fingerprint.

Cite this