Metastatic Castration-Sensitive Prostate Cancer also referred to as mHSPC in literature refers to prostate cancer that still responds to testosterone suppression therapy. Moreover, patients with newly diagnosed metastatic disease and high-risk disease characteristics tend to have a poorer prognosis. In 2018, Zytiga (abiraterone acetate) in combination with prednisone was approved for the treatment of metastatic high-risk CSPC.
Approval in this category was based on the results of the Phase III LATITUDE trial. Before this, Zytiga was approved in 2011 initially for patients with mCRPC who had received prior chemotherapy and expanded the indication in 2012 for patients with mCRPC.
Do you aware of its Metastatic Castration-Sensitive Prostate Cancer market share?
Moreover, In September 2019, the US FDA also approved Erleada for patients with mHSPC. The efficacy of Erleada was evaluated in TITAN Trial. The findings of this trial have shown statistically significant improvements in both OS and rPFS. At the time of a prespecified interim analysis, the hazard ratio for overall survival was 0.67, and median overall survival was not reached in either arm.
The hazard ratio for the rPFS improvement was 0.48. The median rPFS was not reached with apalutamide plus ADT and was 22.1 months with placebo plus ADT.
With this approval, Janssen has strengthened its spot in the prostate cancer drug market. In contrast, drugs like Zytiga have started facing generic competition from the past few years. Approval of Erleada for mCSPC has put a barrier to the growth of the sales of Zytiga, which is already facing competition.
In December 2019, the US FDA approved Xtandi for patients with mCSPC. Prior to this, the US FDA approved Xtandi for patients with CRPC. With this approval, Xtandi became first and only oral treatment approved by the US FDA in three distinct types of advanced prostate cancer—nonmetastatic and CRPC and mCSPC. The efficacy of Xtandi was investigated in the ARCHES trial (NCT02677896).
All enrolled patients received a GnRH analog or had a prior bilateral orchiectomy. In this study, the main efficacy endpoint was rPFS. However, median rPFS was not reached in the Xtandi arm compared to 19.4 months in the placebo arm. However, a significant improvement reported on the Xtandi arm compared to placebo in time to initiation of a new antineoplastic therapy.
The use of Xtandi plus ADT significantly reduced the risk of radiographic progression or death by 61% compared to placebo plus ADT. At the time of rPFS analysis of this drug, OS data was not established. This approval had put direct competition between Zytiga and Xtandi. Besides, it is anticipated that in coming years, both drugs could hold a considerable market share for mCSPC/HSPC treatment paradigm.
Click here for more info @ Metastatic Castration-Sensitive Prostate Cancer Market Research
Comments