"Coadministration of Apalutamide and Relugolix in Patients with Localiz" by Gordon Brown, Laurence Belkoff et al.
 

Coadministration of Apalutamide and Relugolix in Patients with Localized Prostate Cancer at High Risk for Metastases.

Document Type

Article

Publication Date

1-2023

Publication Title

Target Oncol

Abstract

BACKGROUND: The single-arm, open-label, multicenter, phase II Apa-RP study evaluates the biochemical recurrence (confirmed prostate-specific antigen [PSA] > 0.2 ng/mL)-free rate in patients with high-risk localized prostate cancer (HR-LPC) after radical prostatectomy following adjuvant apalutamide and androgen-deprivation therapy. In this substudy, relugolix, an oral gonadotropin-releasing hormone antagonist, was evaluated in combination with apalutamide.

OBJECTIVE: The aim of this study was to evaluate whether the approved standard maintenance dose of relugolix in combination with apalutamide sustains castrate testosterone levels (< 50 ng/dL).

PATIENTS AND METHODS: Twelve patients with HR-LPC who met all the main study criteria were included in the substudy. Patients received relugolix monotherapy for 2 weeks (loading dose [360 mg] at Day - 14 then 120 mg/day daily until Day - 1), then daily relugolix (120 mg) with apalutamide (240 mg) from Day 1 to Day 28. Endpoints were rate of maintained castration (testosterone < 50 ng/dL) through Day 28 (primary) and safety (secondary).

RESULTS: All 12 patients received relugolix and apalutamide and achieved castrate testosterone levels after 2-week relugolix monotherapy (median testosterone 348.5 ng/dL and 8.7 ng/dL at Days - 14 and - 1). All 11 patients who had testosterone measured at Day 28 maintained castrate testosterone (median 10.0 ng/dL) without relugolix dose adjustment. Treatment-emergent adverse events (TEAEs) occurred in nine patients during relugolix monotherapy and in eight patients during relugolix + apalutamide coadministration. Hot flush was the most common TEAE reported, in six and four patients, respectively.

CONCLUSIONS: Relugolix administered at approved standard doses concurrently with apalutamide was effective in maintaining castrate testosterone levels in HR-LPC without new safety signals.

TRIAL REGISTRATION NUMBER AND DATE: NCT04523207, 21 August 2020.

Volume

18

Issue

1

First Page

95

Last Page

103

DOI

10.1007/s111523-022-00932-8

ISSN

1776-260X

PubMed ID

36472728

Share

COinS