Testing the Effects of Oxybutynin for the Treatment of Hot Flashes in Men Receiving Hormone Therapy for Prostate Cancer

Summary

This phase II trial compares the effect of oxybutynin versus placebo for reducing hot flashes in men receiving androgen deprivation (hormone) therapy for the treatment of prostate cancer . Androgen deprivation therapy decreases testosterone and other androgens through medications or surgical removal of the testicles. Relative to placebo, low- or high-dose oxybutynin may reduce hot flashes in men receiving androgen deprivation therapy.

Timeline

Start

2021-10-28

Primary completion

2024-02-05

Completion

2024-03-11

Outcome

Met primary endpoint

registry analysis (superiority test); High-dose Oxybutynin Chloride vs Placebo; p = 0.0019; Mean Difference (Final Values) -9.11 (90% CI -13.76 to -4.46); t-test, 2 sided NCT04600336 ↗

paper Daily hot flash scores for placebo, 2.5 mg oxybutynin, and 5 mg oxybutynin reduced by an average of 4.85, 9.94 (P = .07), and 13.95 (P = .002) points, respectively. PMID 41587370 ↗

Publications

• Stish BJ, Mazza GL, Nauseef JT, Humeniuk MS, Smith TJ, Tofthagen C, Diaz Pardo DA, Chay C, Huang AJ, Naha K, Tagawa ST, Chow S, Ruddy KJ, Lustberg MB, Adams-Campbell LL, Novotny PJ, Loprinzi CL. Alliance A222001: Oxybutynin Versus Placebo for the Treatment of Hot Flashes in Patients Receiving Androgen-Deprivation Therapy for Prostate Cancer. J Clin Oncol. 2026 May;44(13):1198-1205. doi: 10.1200/JCO-25-01486. Epub 2026 Jan 26.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Oxybutynin	Small molecule	2.5 mg	Oral
Subject	Oxybutynin	Small molecule	5 mg	Oral

Indications