LHRH drugs, like Lupron or Zoladex, are the primary drugs used for androgen suppression. In this study of 200 men, some were on Lupron and others on Zoladex. When the first drug failing, they switched to the other drug. Did it help? Nope. This is not surprising as the drugs have identical ways of working.
Shen YC, Kang CH, Chiang PH. 2016. Efficacy of switching therapy of luteinizing hormone-releasing hormone analogue for advanced prostate cancer. Kaohsiung J Med Sci 32(11):567-571. www.ncbi.nlm.nih.gov/pubmed/27847099