LATITUDE PROs Support Upfront Abiraterone Acetate Plus Prednisone With ADT

Patient-reported outcomes are better for men undergoing androgen deprivation therapy for metastatic, castration-naïve prostate cancer when abiraterone acetate plus prednisone are added to the regimen

medwireNews: For men with a new diagnosis of metastatic, castration-naïve prostate cancer (CNPC), research shows that the addition of abiraterone acetate plus prednisone to androgen deprivation therapy (ADT) improves pain, prostate cancer symptoms, fatigue, functional decline and health-related quality of life (HRQoL).

These patient-reported outcome (PRO) results from the LATITUDE trial add to the previously reported findings of improved overall and radiographic progression-free survival with the steroidal CYP17A1 inhibitor regimen compared with ADT plus placebo in the high-risk patient population.

“When the results of this analysis are considered in combination with the overall survival data from the LATITUDE trial, clinicians should feel assured that this regimen will benefit patients with metastatic castration-naïve prostate cancer”, writes David Penson, from Vanderbilt University Medical Center in Nashville, Tennessee, USA, in a comment accompanying the PRO findings in The Lancet Oncology

All patients in the trial were given daily ADT; the 597 patients randomly assigned to receive abiraterone acetate 1000 mg/day plus prednisone 5 mg/day were followed-up for a median of 30.9 months, while the 602 patients assigned to receive placebo were followed-up for a median of 29.7 months. 

The median time to worst pain intensity, according to the Brief Pain Inventory–Short Form, was not reached in either arm of the trial. Nevertheless, patients given abiraterone acetate plus prednisone had a longer median time until 25% of the group reached this endpoint than the placebo arm, at 11.07 versus 5.62 months, giving a significant hazard ratio (HR) of 0.63. 

The median time to pain interference progression was unreached in the abiraterone plus prednisone-treated patients versus 18.4 months for controls, with 25% of the groups reaching this endpoint at 6.5 versus 3.7 months and a significant HR of 0.67, although time to average pain progression did not significantly differ between the groups. 

Median time to worst fatigue intensity was not reached in either group but the time taken for 25% of patients to reach this endpoint significantly differed, at 18.4 months for patients given abiraterone acetate plus prednisone versus 6.5 months for controls (HR=0.65). 

And median time to deterioration of functional status using the Functional Assessment of Cancer Therapy Prostate scale total score in the groups was 12.9 versus 8.3 months, giving a significant HR of 0.85.

The benefit of abiraterone acetate plus prednisone over placebo was also reflected in the improved general health status scores on the EQ-5D-5L measure of HRQoL throughout the study period, report Kim Chi, from B C Cancer–Vancouver Centre in British Columbia, Canada, and co-investigators. 

“Treatment with ADT plus abiraterone acetate and prednisone led to longer median time to deterioration of physical wellbeing; however, median time to deterioration of functional, emotional, and social and family wellbeing did not differ significantly between treatment groups”, the authors observe. 

“These results might have been anticipated since wellbeing domains are qualitative and affected by multiple aspects of life and are therefore less likely to be dependent on disease and treatment factors”, they suggest. 

David Penson discusses further the “compelling” LATITUDE findings in the light of the CHAARTED trial, which showed similar overall survival benefit with the addition of docetaxel to ADT but no HRQoL benefit for the first year. 

Writing that the question is no longer whether to combine abiraterone acetate plus prednisone or docetaxel to ADT for metastatic CNPC but which agent to add first, he notes that the greater upfront cost of abiraterone may be offset by the greater impact of adverse events on HRQoL with the taxane. 

“We will therefore have to consider quality-adjusted life years and the cost-effectiveness of each of the available combination therapies to choose the optimum treatment for each patient”, the commentator summarises. 

And he concludes: “Although studies addressing these issues are yet to be done, the PRO results from the LATITUDE trial represent an important first step in this direction.”

References

Chi KN, Protheroe A, Rodríguez-Antolín A, et al. Patient-reported outcomes following abiraterone acetate plus prednisone added to androgen deprivation therapy in patients with newly diagnosed metastatic castration-naive prostate cancer (LATITUDE): an international, randomised phase 3 trial. Lancet Oncol; Advance online publication 8 January 2018. DOI: http://dx.doi.org/10.1016/S1470-2045(17)30911-7

Penson DF. Considering quantity and quality of life in metastatic castration-naïve prostate cancer. Lancet Oncol; Advance online publication 8 January 2018. DOI: http://dx.doi.org/10.1016/S1470-2045(17)30908-7

medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group