Abiraterone/Prednisone May Best Enzalutamide for QOL in Advanced Prostate Cancer

By Marilynn Larkin

October 24, 2019

NEW YORK (Reuters Health) - For patients with metastatic castration-resistant prostate cancer (mCRPC), abiraterone plus prednisone may offer a better quality of life than enzalutamide, a 12-month analysis of the observational Aquarius study suggests.

"Traditionally, clinical trials of novel cancer therapies capture physical side effects that occur. As more drugs impact the treatment landscape for patients, information regarding the patient experience on these treatments is needed," Dr. Alison Reid of The Royal Marsden NHS Foundation Trust told Reuters Health by email.

"While pre-existing medical conditions/ medications might mandate choosing (one) over the other, frequently patients have a choice between the two drugs," she noted.

"The Aquarius trial gathered patient-reported information prospectively in a real-world setting about what it was like to take these medications," said Dr. Reid, who was UK Principal Investigator of the study. "It demonstrated that patients experienced less fatigue and cognitive impairments - including memory loss and reduced thinking abilities - with abiraterone acetate plus prednisone than with enzalutamide."

"This is important information that may inform the decision making of patients and doctors about which of these drugs to select," she said. "Future trials should endeavor to incorporate similar assessments."

Aquarius was a prospective, 12-month observational study in patients with mCRPC from Denmark, France, and the UK. Abiraterone or enzalutamide was given according to routine practice (i.e., nonrandomized).

Patient-reported outcomes (PROs) were collected using the Functional Assessment of Cancer Therapy - Cognitive Function (FACT-Cog); Brief Fatigue Inventory--Short Form (BFI-SF); Brief Pain Inventory--Short Form; and European Organisation for Research and Treatment of Cancer - Quality of Life Questionnaire (QLQ-C30) at baseline and during routine visits.

Outcomes included mean change in PROs; clinically meaningful worsening in PROs, and safety.

Interim three- and six-month analyses of Aquarius showed more favorable outcomes were achieved with abiraterone than with enzalutamide for PROs of cognition and fatigue. As Dr. Reid noted, the current study, published online October 5 in European Urology, reports the 12-month study results.

One hundred and five abiraterone-treated patients and 106 patients treated with enzalutamide were included in the analysis. The median age was 76 and median time from mCRPC diagnosis was 1.4 months. Mean overall treatment duration was 38.3 weeks for abiraterone and 38.7 for enzalutamide.

The key PRO items - cognitive impairments and fatigue - were significantly in favor of abiraterone versus enzalutamide during the study.

Specifically, "Perceived cognitive impairment" and "comments from others" (FACT-Cog); "fatigue right now", "usual level of fatigue", and "worst level of fatigue" (BFI-SF); and "cognitive functioning" and "fatigue" (QLQ-C30) were significantly in favor of abiraterone over enzalutamide for three or more consecutive periods up to month 12.

From the outset, significantly fewer patients receiving abiraterone experienced one or more episodes of clinically meaningful worsening in cognition and fatigue.

Adverse events - i.e., fatigue and asthenia - were lower with abiraterone than with enzalutamide (5% vs. 15% and 10% vs. 11%, respectively).

There were no treatment-related deaths.

Coauthor Dr. Antoine Thiery-Vuillemin of the Department of Medical Oncology, CHU Jean MINJOZ, in Franche-Comte, commented in a separate email to Reuters Health, "The data... show a better quality of life with abiraterone plus prednisone, and it is seen early. This is in line with other published data."

"All of this strengthens the message from this study, which might not be called 'practice-changing' but definitely highlights a very important point when choosing anti-cancer treatment: the clinical impact of the drugs, but assessed by the patient," he said.

Dr. David Chen of the department of surgical oncology at Fox Chase Cancer Center in Philadelphia commented by email, "The article may be confounded on non-defined selection bias, since use of abiraterone or enzalutamide was at the discretion of the treating physician, and patients were not randomized to therapy. However, this is less likely since the findings are consistent with outcomes...in prior randomized trials."

"While the rate of severe adverse events recorded in this study appears to be infrequent with either treatment, it may be under-reported due to the study's observational design," he noted.

"The results suggest an advantage to use of abiraterone over enzalutamide, but there may be certain patient populations that may show different results," he added. "Patients having any prior chemotherapy treatment were excluded, so it is not clear if patients with prior docetaxel treatment would have similar outcomes, and that abiraterone should be favored as the initial treatment selection for those men."

The study was supported by Janssen EMEA. Drs. Thiery-Vuillemin and Reid and three coauthors have received fees from the company, and four coauthors are employees.

SOURCE: http://bit.ly/2JhHhxn

Eur Urol 2019.