ASCO 2024: A Randomized Phase II Study of ADT + Abiraterone Versus ADT + Abiraterone + Docetaxel in Patients with Low-Volume Metastatic Hormone-Sensitive Prostate Cancer

(UroToday.com) The 2024 American Society of Clinical Oncology (ASCO) Annual Meeting held in Chicago, IL between May 31st and June 4th, 2024 was host to a prostate, testicular, and penile cancers trials in progress poster session. Dr. Sarah Fenton presented a randomized phase II study of ADT + abiraterone acetate +/- docetaxel in patients with low-volume metastatic hormone-sensitive prostate cancer (mHSPC).

 

The ARASENS and PEACE-1 trials have demonstrated an overall survival benefit for triplet therapy with combination ADT + docetaxel + an androgen receptor pathway inhibitor (ARASENS: darolutamide, PEACE-1: abiraterone acetate/prednisone), compared to doublet therapy with ADT + docetaxel.1,2 However, to date, it remains unknown whether the addition of docetaxel to a doublet regimen of ADT + an androgen receptor pathway inhibitor improves overall survival, and this has not been evaluated in a randomized clinical trial. Additionally, both trials have demonstrated that the benefit of androgen receptor pathway inhibitor addition to ADT + docetaxel appears to be most significant in patients with CHAARTED high-volume disease.3 The benefit was less clear in low-volume disease patients, which may be due to the use of docetaxel as the control arm in this patient population. In order to address these current gaps in the literature, Dr. Fenton and colleagues designed a phase II trial to evaluate the addition of docetaxel to ADT + abiraterone in patients with low-volume mHSPC.

 

This is a multicenter phase II trial (NCT06060587) that is randomizing mHSPC patients with evidence of CHAARTED low-volume disease on conventional imaging (CT/MRI and bone scan) to either:

  • ADT (physician choice) + abiraterone/prednisone (1,000 mg/5 mg daily) + docetaxel (75 mg/m2 every 3 weeks for 6 cycles)
  • ADT + abiraterone/prednisone

 

Patients may have started ADT up to twelve weeks prior to randomization. Recurrent prostate cancer and exposure to ADT prior to the diagnosis of metastatic disease are allowed, as is concurrent treatment with radiation therapy.

 

The primary study endpoint is radiographic progression free survival (rPFS). Secondary endpoints include:

  • Overall survival
  • PSA response rate
  • Overall response rate
  • Time to castration resistant prostate cancer
  • Time to initiation of subsequent anti-neoplastic therapy
  • Quality of life assessments
  • Safety

 

Enrollment in this trial began in December 2023 and is open at the Robert H. Lurie Comprehensive Cancer Center of Northwestern University and other satellite sites affiliated with Northwestern University.

 

Presented By: Dr. Sarah Elizabeth Fenton, MD, PhD, Assistant Professor, Department of Medicine, Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL

 

Written By: Rashid Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting, Chicago, IL, Fri, May 31 – Tues, June 4, 2024.

References:

  1. Smith MR, Hussain M, Saad F, et al. Darolutamide and Survival in Metastatic, Hormone-Sensitive Prostate Cancer. N Engl J Med. 2022 Mar 24;386(12):1132-1142.
  2. Fizazi K, Foulon S, Carles J, Roubaud G, et al. Abiraterone plus prednisone added to androgen deprivation therapy and docetaxel in de novo metastatic castration-sensitive prostate cancer (PEACE-1): A multicentre, open-label, randomized, phase 3 study with a 2 x 2 factorial design. Lancet. 2022 Apr 30;399(10336):1695-1707.
  3. Hussain M, Tombal B, Saad F, et al. Darolutamide plus androgen-deprivation therapy and docetaxel in metastatic hormone-sensitive prostate cancer by disease volume and risk subgroups in the phase III ARASENS trial. J Clin Oncol. 2023 Jul 10;41(20):3595-3607.
  4. Fizazi K, Tran N, Fein L, et al. Abiraterone plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer. N Engl J Med. 2017;377(4):352-360.