As mentioned before, Gilead has their own ongoing metastatic castrate resistant prostate cancer (mCRPC) Phase 1/2 trial entitled "Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of GS-5829 as a Single Agent and In Combination With Enzalutamide in Participants With Metastatic Castrate-Resistant Prostate Cancer" (NCT02607228) with their BET inhibitor GS-5829 by itself and in combo with enzalutamide. This trial was first received at ClinicalTrials.gov on November 16, 2015, so not too much earlier than Zenith's trial.

DM mentioned in the Zenith webcast that their next indication they are going after is breast cancer (triple-negative breast cancer (TNBC), ER+ breast cancer). Coincidentally, Gilead has a trial that is not yet recruiting entitled "GS-5829 in Combination With Exemestane or Fulvestrant Comparing With Exemestane or Fulvestrant Alone in Women With Advanced Estrogen Receptor Positive HER2- Breast Cancer" (NCT02983604). This one was first received at ClinicalTrials.gov on December 2, 2016, so it is very recent.

DM also said in the webcast that Zenith has gone from being behind in the BET inhibitor/oncology field, to being caught up, to now being in the lead. I am mildly concerned about this competition with Gilead, since there seems to be a parallel between Zenith and Gilead in the indications they are going after. I have very little info on GS-5829. It is likely also considered a next-generation BET inhibitor, but I am basing that entirely on the fact that their only other trial with GS-5829 entitled "Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of GS-5829 in Adults With Advanced Solid Tumors and Lymphomas" (NCT02392611) was first received at ClinicalTrials.gov in March 2015. That is quite recent relative to some of the other BET inhibitor oncology trials that other companies started a few years before that.

A few months behind Gilead in terms of start date for the mCRPC or TNBC trials isn't too concerning. They will likely sink or swim together.

BearDownAZ