We have many new drugs to treat metastatic castrate resistant prostate cancer (mCRPC), but not all men have a positive result to each of the drug. Understanding who might obtain a positive result to a specific drug prior giving it will save both the individual man and society time and money.
Understanding this it becomes clear that we neeed to develop ways to identify those men who are more likely to benefit from a particular therapy prior to starting it. In an attempt to move tis goal forward, researchers reviewed the outcome of men treated with abiraterone (Zytiga) at their Institution to describe factors predictive for response.
They identified the men with CRCP who were treated with abiraterone. From electronic records they identified the baseline variables and potential prognostic factors in this group. They evaluated the outcome measures in these men, they included overall survival (OS), prostate-specific antigen (PSA) response and time to PSA progression (TTPP). The Kaplan-Meier method and Cox proportional hazards model were used to analyze survival data.
They had a total of 61 men who met their inclusion criteria. They found that three independent predictors of overall survival (OS) were identified: Duration of response to androgen deprivation therapy (ADT), performance status and baseline hemoglobin levels.
This was a retrospective, single institutional analysis with a small sample so additional research to validate these findings should be performed. In additional, similar analysis of the other drugs used to treat mCRPC should also be performed.
Anticancer Res. 2015 Feb;35(2):1057-63, Afshar M, Al-Alloosh F, Pirrie S, Rowan C, James ND, Porfiri E.
PMID: 25667494
Joe T. Nowak, M.A., M.S.W.
Based on approved (US) labelling, which of the two drugs do you believe has the best overall profile in the pre-chemotherapy setting? Which one has more risk of developing resistance?
I believe that Xtandi is a superior drug because it doesn’t require the concurrent use of a steroid drug. We have no information that I am aware of which answers your question about which presents a higher risk of creating some cross resistance. – Joel