AUTHOR=Lara Pedro C. , Rodríguez-Melcón Juan I. , Palacios-Eito Amalia , Lozano Antonio , Hervás-Morón Asunción , Villafranca Elena , Gómez-Iturriaga Alfonso , Sancho Gemma , Maldonado Xavier 

TITLE=Phase II Study of ENZAlutamide Combined With Hypofractionated Radiation Therapy (ENZART) for Localized Intermediate Risk Prostate Cancer

JOURNAL=Frontiers in Oncology

VOLUME=Volume 12 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.891886

DOI=10.3389/fonc.2022.891886

ISSN=2234-943X

ABSTRACT=Background: Intermediate-risk prostate cancer (PCa) is usually treated by a combination of external beam radiation therapy (EBRT) and a short course of androgen deprivation therapy (ADT). ADT is associated with multiple side effects including weight gain, loss of libido and hot flashes. In contrast, anti- androgen monotherapy has been generally better tolerated in spite of higher rates of gynecomastia.


Objective: To assess the effectiveness of enzalutamide monotherapy combined with hypofractionated EBRT (Hypo-EBRT) in the treatment of intermediate risk prostate cancer.


Method: This trial was a multicenter, open label phase II study of 6 months of enzalutamide monotherapy combined with Hypo-EBRT for intermediate risk prostate cancer. Hypo-EBRT was initiated at 8th -12th weeks after initiating enzalutamide. The primary endpoint was PSA decline >80% measured at the 25th week of enzalutamide administration. Secondary end-points included assessment of toxicity, changes in anthropomorphic body measurement, sexual hormones and metabolic changes.


Results : Sixty-two patients were included in the study from January 2018 to February 2020. PSA decline >80% was observed in all evaluable patients at the end of enzalutamide treatment and 92% achieved PSA values under 0.1ngr/mL. All patients remain in PSA response (<80% reduction of the initial values) 6 months after the end of
 
enzalutamide treatment. The most frequent adverse events were hypertension, asthenia and gynecomastia. There were no significant changes in bone density, body mass index (BMI), or patient-reported outcomes (PROs).


Conclusion: Enzalutamide monotherapy is very effective in combination with hEBRT in reducing PSA levels for patients with intermediate risk prostate cancer. Future randomized trials comparing adjuvant enzalutamide versus ADT, in this particular clinical situation are encouraged.