HRT-PC Trial: Hormone Recovery After Treatment for Prostate Cancer Trial. An Open-label Phase II Study of Clomiphene Citrate in Patients With Persistent Hypogonadism After ADT for Treatment of Localized Prostate Cancer

The purpose of this phase II trial is to assess the clinical utility of clomiphene citrate for the augmentation of testosterone in prostate cancer survivors who complete androgen deprivation therapy (ADT), including the efficacy and tolerability of clomiphene, patient-reported quality of life outcomes, metabolic effects, biomarkers of response, and the oncologic safety of increasing testosterone. Up to 83 eligible participants who have completed radiation and ADT for non-metastatic prostate cancer will participate in this study. Participants are assigned to one of two cohorts: Cohort A is comprised intermediate-risk survivors who underwent short-course ADT (4-17 mo.) and are hypogonadal ≥6 months after ending ADT, and Cohort R is comprised of survivors who recovered to eugonadal levels of testosterone (≥ 300 ng/dL) within 6 months after ending ADT. Participants will be evaluated for clinical findings, toxicities, laboratory abnormalities (CBC, CMP, Lipid panel, Hgb A1C), changes to the hypothalamic-pituitary-gonadal axis (E2, LH, FSH, TT) \[dependent on Cohort\], biochemical recurrence (PSA), and quality of life (FACT-P, FACT-Fatigue, qADAM). Cohort R is an observational natural-recovery control group and will not be treated. Cohort A will be treated with oral clomiphene citrate, 25 mg, once daily for 6 months, then tested for persistence of response (eugonadal testosterone) after a 1-month washout period. After completing study assessments, participants will transition to standard survivorship follow-up. Thereafter, long-term health outcomes will be reviewed to determine the rates of biochemical recurrence and metastasis after 5 years.

Inclusion Criteria: 1. Histologic diagnosis of adenocarcinoma of the prostate 2. No evidence of metastatic disease 3. Prior definitive local therapy with radiation 4. Prior definitive continuous ADT 4-17 months in duration (treatment may include abiraterone). 5. Available serum testosterone measurement. Testosterone \< 300 ng/dL is required for inclusion in Cohort A; testosterone ≥300 ng/dL is required for inclusion in Cohort R. 6. PSA \