ChemoCentryx, Inc. (NASDAQ:CCXI) Q2 2018 Earnings Conference Call - Final Transcript
Aug 09, 2018 • 05:00 pm ET
(Operator Instructions). Our first question comes from the line of Konstantinos Aprilakis with JMP Securities.
Congrats on the early enrollment completion for ADVOCATE. So regarding ANCA-associated vasculitis, can you talk about how you envision avacopan, ultimately, being used in the clinic, given that patients in the trial are likely taking either cyclophosphamide or rituximab? Is there a reason to believe that either combo might be more efficacious?
Thank you, Konstantinos. Yes, we are -- we're agnostic as to what background medication is being taken, cyclophosphamide or rituximab. This is based on our experience in Phase II where, again, we had a relatively even mix across the 2 trials of those background medications and the numbers don't seem to change, at least from the Phase II data we have so far.
Moreover, we know from published precedent when rituximab was originally approved for use instead of cyclophosphamide and again, this is all against the backdrop of normal high-dose chronic steroid therapy over a 6-month time frame, with tapering of the steroids. But the numbers weren't all that different. Patients were in signs and symptoms remission, if you will, by 6 months at about 60% average rate, a little bit higher on the rituximab group, 64% versus 53% in the cyclophosphamide plus steroid group versus rituximab plus steroid, and those were certainly significant at the level of non-inferiority, suggesting rituximab was doing as well with signs and symptoms control as the standard of care.
So -- but the numbers were not sufficiently different to cause us to change any of our models about whether or not those background therapies would affect what was happening with avacopan and indeed, data to date from the Phase II program suggest that they do not affect. So how will this be used, ultimately? Well, the first thing, and again, I'm sure most folks will recall, initially, what we are trying to do is dramatically reduce or even eliminate the need for chronic high doses of steroids in this patient population.
The steroid load contributes fundamentally to strongly to the total burden of the disease because the steroids themselves, as you know, cause tremendous problems in these patient populations. So that is what we aim to do, and that's what we're testing very carefully in the ADVOCATE trial. Some may ask me, ultimately, do you think these other agents are useful at all?
Maybe with the precise mode of action of avacopan and since it is a neutrophil-driven disease, driven by activation of complement down to the C5a, C5a receptor level, maybe even rituximab and cyclophosphamide are not actually going to be that useful. Well, ultimately, we will test this in the clinic, preclinical modeling does tell us, however, that in very thorough models of ANCA disease in rodent systems, you don't need to inhibit anything but the C5a receptor, and those data are published by us and others. So who knows what the long-term approach will be, but our next step is to simply try to make