Feng, Felix YThomas, ShibuSaad, FredGormley, MichaelYu, Margaret KRicci, Deborah SRooney, BrendanBrookman-May, SabineMcCarthy, SharonOlmos, DavidChowdhury, SimonHadaschik, BorisLiu, YangDavicioni, ElaiSmith, Matthew RSmall, Eric J2023-02-092023-02-092021http://hdl.handle.net/10668/17947There is a need to identify prognostic biomarkers to guide treatment intensification in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). To examine whether molecular subtypes predict response to apalutamide, using archived primary tumor samples from the randomized, double-blind, phase 3 SPARTAN trial. In this cohort study, gene expression data from 233 archived samples from patients with nmCRPC enrolled in the SPARTAN trial were generated using a human exon microarray. The present analysis was conducted from May 10, 2018, to October 15, 2020. Patients were randomized (2:1) to apalutamide, 240 mg/d, with androgen deprivation therapy (apalutamide+ADT) or placebo+ADT. Patients were stratified into high-risk and low-risk categories for developing metastases based on genomic classifier (GC) scores for high (GC >0.6) and low to average (GC≤0.6) and into basal and luminal subtypes; associations between these molecular subtypes and metastasis-free survival (MFS), overall survival (OS), and progression-free survival 2 (PFS2) were evaluated using Cox proportional hazards regression and Kaplan-Meier analysis. Median age of the 233 included patients was 73 (range, 49-91) years. A total of 116 of 233 patients (50%) in the SPARTAN biomarker subset had high GC scores. Although all patients receiving apalutamide+ADT had improved outcomes, having high GC scores was associated with the greatest improvement in MFS (hazard ratio [HR], 0.21; 95% CI, 0.11-0.40; P  The findings of this study suggest that the GC score and basal-luminal subtype derived from archived tumor specimens may be biomarkers of response to apalutamide+ADT in the nmCRPC setting. Although overall, the addition of apalutamide to ADT was beneficial, higher-risk and luminal subtypes appeared to benefit most. Obtaining GC scores may be useful for identifying patients for early treatment intensification with apalutamide, and basal-luminal subtyping may be a beneficial approach for patient selection for further treatment intensification in trials combining novel therapies with apalutamide.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/AgedAged, 80 and overAndrogen AntagonistsAndrogen Receptor AntagonistsCohort StudiesHumansMaleMiddle AgedProstatic Neoplasms, Castration-ResistantThiohydantoinsTreatment Outcomeresearch article34081076open access10.1001/jamaoncol.2021.14632374-2445PMC8176389https://jamanetwork.com/journals/jamaoncology/articlepdf/2780477/jamaoncology_feng_2021_oi_210018_1626360255.64836.pdf