ChemoCentryx Inc (CCXI) 2021 Q2 法說會逐字稿

Good afternoon, and welcome to the ChemoCentryx Second Quarter 2021 Financial Results Conference Call. (Operator Instructions) As a reminder, this conference call will be recorded.

I would now like to turn the call over to Lee Roth of Burns McLellan. Mr. Roth, please go ahead.

Thank you, Paul. Good afternoon, and welcome to the ChemoCentryx Second Quarter 2021 Financial Results Conference Call. Earlier today, the company issued a press release providing an overview of its financial results for the quarter ended June 30, 2021. And a copy of this release, along with a few slides that you may find helpful while you listen to the call, are available on the Investor Relations section of our website at www.chemocentryx.com.

Joining us on the call today is Dr. Thomas Schall, President and Chief Executive Officer of ChemoCentryx, who will review the company's recent business and clinical progress. Following his comments, Susan Kanaya, Executive Vice President, Chief Financial and Administrative Officer, will provide an overview of the company's financial highlights for the quarter before turning the call back over to Tom for closing remarks. Tausif Tosh Butt, Executive Vice President and Chief Operating Officer, will then join Tom and Susan for the Q&A session.

During today's call, we will be making certain forward-looking statements. As explained on Slide 2 of the presentation, these forward-looking statements are based on current information, assumptions and expectations that are subject to change and involve a number of risks and uncertainties that may cause actual results to differ materially from those contained in the forward-looking statements. These risks are described in the company's filings made with the Securities and Exchange Commission, including our annual report on Form 10-K filed on March 1, 2021. You are cautioned not to place undue reliance on these forward-looking statements, and ChemoCentryx disclaims any obligation to update such statements.

In addition, this call contains time-sensitive information accurate only as of the date of the live broadcast, August 9, 2021. ChemoCentryx undertakes no obligation to revise or otherwise update any forward-looking statements to reflect events or circumstances after the date of this live conference call.

With that, it's now my pleasure to turn the call over to Thomas Schall. Tom?

Thank you, Lee, and good afternoon, to everyone listening. Thank you for joining us on our second quarter 2021 conference call.

Please move to Slide 3 in our presentation. Many years ago, we at ChemoCentryx embarked on a voyage of discovery and development with our lead candidate avacopan in the treatment of ANCA-associated vasculitis in order to see if we might improve lives of patients with that rare but often organ-threatening or even life-threatening disease. Our science, which was and is unlike that of any other sponsor, show that the C5a receptor inhibition might constitute an entirely new mode of therapeutic action in the treatment of that disease.

This mode of action was a specific way of arresting complement-driven inflammatory cells that are at the very core of tissue and organ destruction in ANCA vasculitis. This mode of action is a highly targeted approach, which was and is attempted for the first time in this disease and quite unlike the broadly immunosuppressive regimens that have been used for nearly 50 years and are still in use today. Urged on by ANCA experts and importantly, too, ANCA patients, we applied ourselves to try to bring something new and useful to the treatment paradigm in ANCA disease.

As most of you know, we progressed avacopan through 2 Phase II trials and then a pivotal Phase III trial. That Phase III trial, ADVOCATE, represents the largest and longest randomized clinical trial ever conducted for a new molecular entity in this relatively rare but often deadly disease. The results of our ADVOCATE trial, we believe, were positive across many therapeutic metrics. And those results, after careful review by peers and data analysts, were published in The New England Journal of Medicine.

One week after I reported to you on our first quarter results, an FDA Arthritis Advisory Committee on May 6 was held and was essentially deadlocked on the key questions posed by the FDA on avacopan for use in ANCA therapy. While disappointed by that discussion, we took to heart the stated idea that we had not yet clearly enough explained the findings and their significance to the agency and to the community at large. We wished to make clear that avacopan could potentially be an additional therapeutic tool to place in the hands of patients and their physicians whose current treatment armamentarium is quite limited in the fight against ANCA vasculitis.

Discussion at the Advisory Committee meeting also illustrated certain dilemmas facing all of us when medical innovation may offer new hope in an orphan disease: a, how do you test the new drug, and how do you assess results in an area of major unmet need when the scarcity of patients limits the realistic size of a trial; and b, how to conduct such a trial given that, pragmatically, it also needs to reflect the practice of real-world medicine if anyone is hoped to enroll in it.

We, as sponsors and innovators in the orphan disease space, struggle with these questions all the time as do our colleagues in regulatory agencies. Because to be clear, in a clinical trial in an orphan disease, available patients are not only rare by definition, but they realistically and ethically expect and must have access to currently available standard care practices while still the trial must rigorously test the key variables of what the new drug can achieve. Such conundrum must be solved if we are to offer to patients new benefits of additional efficacy, better safety or a combination of both.

Every patient able to enroll in an orphan disease trial counts fundamentally. And since enrollable patients are limited in number, all the data one can glean from each and every one of those patients must be carefully harvested and considered. This can sometimes make for complicated trials, but the luxuries of non-orphan disease trials, for example, the feasibility of doing larger studies and additional trials are typically simply not available in rare diseases.

Such were the dilemmas and such was the nature of the discussion underlying the ADVOCATE trial, discussions that we had with experts, with regulators and with patients before we launched the trial. These discussions were productive and to us represented a victory of collaborative thoughts. After the May Advisory Committee meeting, we engaged in a dialogue with the FDA to learn what additional information from the ADVOCATE trial would be useful to them in reaching their decision and to share relevant avacopan data from other disease areas. The agency was helpful and clear in their information requests, and we endeavor to provide additional necessary data and analyses in order to attempt to chart a clearer understanding and path.

On July 6, we announced that the additional information that we provided to the agency was deemed by the FDA to be a major amendment to the NDA for avacopan in ANCA vasculitis. We commend the agency for that judgment and fully support the extension of the PDUFA target date to October 7. There is much important information to be digested, and all parties wish to reach correct conclusions. We stand ready to work productively with the agency during this review time and beyond.

Looking beyond that time, should a license be granted on October 7, we will be ready for a potential U.S. launch. We have established network of specialty pharmacies and distributors. We have been training our product representative professionals and determining the location and characteristics of the highest-need demographics. We have been talking with patient organizations and conducting disease education programs. And we have engaged with payers in allowable interactions of information exchange with the goal of building a strong patient access program to support patients and clinicians in the early months before formulary decisions are made.

So again, should the FDA decide positively on the value of avacopan in this disease area, we will be ready as we have made considerable investments in being prepared to bring the drug to patients. These investments represent not only that considerable type of time, people and money over the last couple of years but an investment in fundamental innovation, which goes back nearly 20 years. All of this has been done in the firm belief that we might improve lives and even save lives. We stand by that conviction.

Outside of the U.S., we expect regulatory decisions on avacopan in ANCA vasculitis later this year from the European Medicines Agency as well as Japan's Pharmaceuticals and Medical Devices Agency. Our partner, Vifor Pharma, is making similar preparation for commercial launches in Europe and Japan. Should avacopan be approved in the territories' license for commercial distribution to Vifor and its sublicenses, Vifor will remit to us royalties in teens to mid-20s percent on potential net sales of one aggregate net sales line.

Turning to Slide 4. We are well underway in our strategic aim to make avacopan pipeline in a drug, with Phase II data supporting its potential in C3 glomerulopathy and in the debilitating and disfiguring skin disease, hidradenitis suppurativa or HS. For us, the conviction that avacopan can help patients who have major unmet need stems from our understanding of the detailed ADVOCATE data and the fact that such data seem interconnected with observations in other diseases.

Increasingly, we find evidence for a pathology driving role of the C5a receptor in other debilitating disorders. These are disorders where we believe that avacopan's novel, precise, targeted mechanism of action could add to the current care, providing additional options for physicians and patients. For example, in HS, hidradenitis suppurativa, we previously reported top line results from our Phase II AURORA trial with a subgroup analysis showing that in the most severe form of HS, the prespecified Hurley Stage III patients for whom almost no effective therapies exist, avacopan demonstrated a statistically higher response than placebo after 12 weeks of therapy, which is guiding our further clinical development. Increasingly, our work at ChemoCentryx provides a strong mechanistic rationale for the therapeutic effect of avacopan in Hurley Stage III and thus the underpinning of our Phase III trial approach.

While it is well-known that extensive subdermal tunnels are a signature feature of Hurley III versus the more moderate Hurley II stage disease, work here at ChemoCentryx, having now examined many HS patient biopsy sections, suggests that even where tunnels exist in the less severe form of Hurley Stage II disease, the very architecture and the immune activation status of these structures is different, with C5a and C5a receptor seeming to play a larger role in the Hurley III disease.

We hope to present our continued work on the C5a, C5a receptor expression and Hurley Stage III patients at the upcoming American Association of Dermatology meeting and other dermatological symposia this year.

As referred to in Slide 5, the AURORA Phase II trial identified: a, an effective dose; b, the patient population that we should target in a Phase III trial; and c, that we could do so with good safety based on the evidence to date. We aim to discuss with the FDA our plans for a pivotal Phase III trial of avacopan in patients with severe HS. Our current thinking is that this will involve approximately 300 to 400 patients across 2 arms using the hidradenitis suppurativa clinical response score or HiSCR as the primary endpoint at 12 weeks with an open-label follow-up period.

With an estimated 30,000 to 50,000 patients in the United States with Hurley Stage III disease, this represents another highly significant indication for avacopan, and we continue to pursue orphan drug designation for Hurley Stage III, HS, patients. We noted also a connection between kidney benefits seen in the ADVOCATE trial of ANCA vasculitis with the ACCOLADE clinical trial of avacopan for the treatment of C3 glomerulopathy or C3G. Both trials showed an improvement in kidney function as measured by estimated glomerular filtration rate or eGFR.

Slide 6 reviews the results from ACCOLADE showing how avacopan treatment in C3G led to an improvement in the estimated glomerular filtration rate as opposed to deterioration in patients in the control arm. eGFR is what most nephrologists would consider to be the gold standard for measuring kidney function. And we find it encouraging that avacopan treatment produced these results in 2 different renal diseases.

Another interesting finding from the ACCOLADE trial is the change in kidney fibrosis progression seen in patients in the placebo arm after they crossed over to the -- to avacopan therapy. The C3G Histologic Index Disease Chronicity score went up during the first 26 weeks for patients on placebo, evidence of the progression of kidney fibrosis. And then it came down when those patients were switched to avacopan in the second 26 weeks, as shown on Slide 7. We are planning to meet with the FDA later this year to discuss evidence of clinical benefit from ACCOLADE.

The kidney improvement effects seen in both ANCA vasculitis and C3G may bode well for our future plans with avacopan in lupus nephritis or LN. Uncontrolled complement activation has been implicated in kidney destruction in LN, and the disease is poorly controlled with broad immunosuppression. So here again, the precisely targeted, novel, potently anti-inflammatory mechanism of action of avacopan may prove to be an important differentiator in therapy for LN.

Our timing for launching clinical development is now the first half of next year, 2022. And we plan to develop in a 2-step process, first, to demonstrate the early effects of avacopan in a focused patient group; and then expanding to a population of the scope, size and length to provide a definitive finding regarding avacopan's potential in this underserved indication. With an estimated prevalence of 65,000 to 100,000 patients in the U.S., lupus nephritis is yet another orphan disease target for avacopan.

So our ambitious plans comprising the pipeline and the drug strategy for avacopan remain entirely undiminished. It is fair to say also that because of our focus on the ANCA vasculitis NDA, however, execution overall in the other non-ANCA avacopan indications is taking a little longer than we had originally planned as we await further clarity on October 7.

As important as avacopan is to our efforts to improve patients' lives with orphan and rare disease, there are also other novel therapies in the ChemoCentryx pipeline of which we are justifiably proud. Please see Slide 8 as we touch briefly on our novel, orally administered small molecule checkpoint inhibitor for the treatment of cancer. CCX559 is a novel, orally administered PD-1/PD-L1 interaction inhibitor.

As referred to on Slide 9, we launched our Phase I clinical trial of CCX559 with site activations shortly before the end of Q2. We are now pleased to report that we have dosed a cancer patient in this trial, and we are already accumulating early data on such things as pharmacokinetics. We remind you of the promising preclinical data, including in vivo tumor data reported at the American Association for Cancer Research earlier this year, where tumor shrinking and tumor remission with CCX559 was clearly evident in our model systems.

CCX559, we believe, based on our in-house work, is differentiated from the very few other small molecule PD-1/PD-L1 inhibitor programs by having better drug-like properties. Direct comparisons suggest CCX559 is more potent and has significantly better in vivo coverage, potentially leading to cumulative advantages, which may be of an order of magnitude better or more than other candidates. We look forward to the results from this study, and we will keep the community posted as to our progress.

I will now turn the call over to Susan to outline our financial position.

Thank you, Tom. Our second quarter 2021 financial results were included in our press release today and are summarized on Slide 11.

Revenue was $1.8 million for the second quarter of 2021 compared to $49.4 million for the same period in 2020. The decrease in revenue from 2020 to 2021 was principally attributable to the acceleration of revenue recognition in 2020 associated with the decision to discontinue development of CCX140 in focal segmental glomerulosclerosis or FSGS.

Research and development expenses were $20.9 million for the second quarter of 2021 compared to $18.8 million for the same period in 2020. This increase was largely due to the manufacture of commercial drug supply in anticipation of the launch of avacopan in the treatment of ANCA-associated vasculitis and higher research and drug discovery expenses, including those associated with the development of CCX559, our orally administered small molecule checkpoint inhibitor. These increases were partially offset by lower Phase II related expenses due to the completion of the avacopan AURORA Phase II clinical trial in patients with HS and the discontinuation of further clinical development of FSGS in 2020.

General and administrative expenses were $19.7 million for the second quarter of 2021 compared to $10.3 million in the same period in 2020. This increase was primarily due to higher employment-related expenses, including those associated with our launch readiness efforts and higher professional fees.

Lastly, we closed June 30, 2021, with $402.6 million in cash, cash equivalents and investments.

Tom?

Thank you, Susan. To summarize our next steps with avacopan, as you can see from Slide 11, we have filed what the FDA has considered a major amendment to our New Drug Application or NDA, and the new target PDUFA date -- goal date is October 7. Should the FDA grant us a license for avacopan in therapy of ANCA-associated vasculitis, we believe we are thoroughly prepared for potential commercial launch soon after this date.

We aim to meet with the FDA later this year on other avacopan-related matters, including a discussion of results of the clinical trial of avacopan in the treatment of C3 glomerulopathy. Also, our intention to launch a Phase III trial of avacopan in Hurley Stage III hidradenitis suppurativa patients as well as our intended study of avacopan in lupus nephritis.

Importantly, apart from the avacopan program, our pipeline continues to develop. We are now in the clinic per plan with our novel and, we believe, best-in-class orally administered small molecule checkpoint inhibitor. Our aspiration is to make CCX559 a part of the next wave of innovation in cancer care.

As Susan has just indicated, we are in a strong position financially to reach key regulatory and clinical milestones. Strength of conviction matters. We believe conviction based on evidence is true science. We strive to be ever more clear on relating the evidence, showing the potential of avacopan to help people with rare but devastating diseases. We realize that the science and medicine around such diseases is frequently but necessarily complicated. We appreciate those who have taken the extra time to understand what we believe can be a valuable new tool to add to the all too few options that patients with such diseases as ANCA-associated vasculitis have so far.

Every patient counts. Every decision we make matters in terms of their well-being and their lives. People just like you and me but suffering from rare diseases are counting on us. It is why we continue to act upon our firm belief in intervening in the complement pathway and its remarkable potential to help patients with rare but devastating diseases. Resolve and resilience lay at the core of ChemoCentryx. Our mission is to help people. We won't stop until we're done.

I will now turn the call over to the operator for your questions. Operator?

(Operator Instructions) Your first question is from Steve Seedhouse with Raymond James.

This is Ryan Deschner on for Steve Seedhouse. Wanted to ask, will you or have you submitted additional data after the data package that was sent in July? And are you currently engaged in labeling discussions?

Thank you for the question. The package we sent in July was very comprehensive indeed. I won't comment beyond what information exchange might have occurred beyond that since our conversations with the FDA are obviously very important.

And as to label discussions, again, I would need to very much respect the FDA's need to very thoroughly and confidentially engage in all manner of discussions and meeting around the label. So I'm going to respectfully put aside any questions on label discussions and label negotiations at this time.

Appreciate that. I can understand that. And then real quick, can you shed some light on which key secondary efficacy endpoints you'll be focusing on in the Phase I and subsequent study for CCX559? And is this an adaptive trial progression?

It is. Well, it's a Bayesian trial design, and so we certainly are going to be looking primarily at safety, pharmacokinetics and pharmacodynamics, but all of the folks in the trial have some form of cancer. And so we will be secondarily looking on -- looking at tumor progression as well. And we'll have more to say about the details of that trial as soon as we get through this very first step, and we can talk a little bit more about drug coverage in pharmacokinetics.

Your next question is from Michelle Gilson with Canaccord.

I was hoping for avacopan in AAV that you could help us understand a bit more the additional data that you submitted. You mentioned the safety data from HS and C3G trials. And am I understanding your comment earlier correctly that the FDA specifically requested these data from you? Or was this, I guess, interaction more a response on your part to the issues that the FDA identified or expressed?

Thank you, Michelle. So we had a lot of active dialogue and engagement with the agency following the Advisory Committee meeting. I think we developed a much better understanding of all of their issues and concerns. So our amendment was prepared with those kind of learnings in mind.

So for example, yes, we thought it would be very useful to help the agency [understanding there] was additional safety data from avacopan in the AURORA hidradenitis suppurativa trial as well as in the ACCOLADE C3G trial. So we supplied that. There were a couple of other issues that came out of the AdCom, which we very much wish to clarify, help understand the use and analysis of non-study supplied glucocorticoids, i.e., those that are outside the standard steroid taper that we supplied in the kit and the relevance on glucocorticoid toxicities of those glucocorticoids overall and proactively addressing some other concerns in sort of proposed label indications and such like.

So to the extent who asked what and who proactively gave what, it's kind of obscured in just the richness and extensive nature of those discussions and back and forth. But suffice it to say, I believe that all the items that we added, including the safety data, will help the agency have a clearer picture of the properties of the drug and help them make their decision based on the fullness of the data.

And if I could just do one more, with the EMA, a few years ago, you actually submitted a CMA and had that accepted and went through the -- or the CMA process. Did that, I guess, process give you a better line of sight going through the CHMP in terms of what matters to the EMA around the avacopan submission in AAV? Do you feel pretty confident that you understand the EMA's, I guess, view of the data and of the program as a whole from, I guess, your process a few years ago?

Yes, you're quite right, Michelle. A few years ago, based on the 12-week Phase II data from the CLEAR trial, where there was very good evidence that we could, with avacopan, eliminate the daily oral prednisone taper at least through the 12 weeks that we were using the drug in the trial, we put in a conditional marketing authorization approval application that was evaluated extensively by the EMA. So we got a lot of excellent experience from that. I do think it's been helpful in the MAA or the full marketing authorization approval process.

But to be clear, at the time we were controlling the CMA as ChemoCentryx, subsequently now, when we license the commercial rights to Vifor Pharma and their collaboration with Fresenius through Vifor International or Vifor Pharma -- Vifor Fresenius Medical Care Renal Pharma, they're technically responsible for that filing. And so you would have to ask them about details about whether they found our previous experience and the data and knowledge that we were able to impart to them to be useful. But certainly, I think we had some major excellent learnings from that. And with very technical areas in CMC and so forth, I thought it was an invaluable experience for the program.

Okay. And for C3G, what is the gating factor for requesting an FDA meeting? Are you waiting for data to accrue or something else before you meet with the FDA?

Yes. With absolute candor about this, and I alluded to it in my remarks, we just would like to have more clarity on what's going on with ANCA vasculitis. We don't want -- although C3G is in the -- with a different division per se, we would prefer the agency through all divisions to not get distracted with any other applications or intense discussion right now. So clarity on October 7 is, I think, what we're looking for. And once we have that clarity, we will then decide exactly how to engage. But we'll be very -- we're ready to do a number of things as quickly as possible.

Good luck from here to October 7. Obviously, October 7 is the best day of the year. So...

[It really is for many reasons]. Thanks.

Thank you.

Your next question is from Joseph Schwartz with SVB Leerink.

I was just hoping to ask, when you say that you'll be prepared to launch avacopan if it were to gain licensure, since it's been a little while, and obviously, a lot has happened between the company and the FDA, I was wondering if there's been any change to the positioning of avacopan in AAV. Are you prepared for more scenarios now? And is there any change to the range of value and pricing that you think the drug might have in the "real world" if it is able to be approved?

Very good questions, Joe. I'll answer some of them quite generally but, I think, hopefully informatively. Listen, there is still an immense need for this kind of therapy in the ANCA-associated vasculitis community. A delay of 3 months, I don't think changes fundamentally that demand. All will depend, of course, on what the FDA decides if they decide to give us a license, and that is, of course, their decision and then, of course, the details of how the -- what the label looks like.

But having said all that, I don't see big changes in how we position the drug at all. Physician input continues to be very strong, that they would love to see this drug approved so that they have an additional tool to use. The patient input continues to be very, very strong. They would very much like to see this drug approved. They feel they have very limited options, and they do. I mean there's only been one drug really approved for this indication in the U.S., and that's rituximab, which is always used in combination with, as you know, various doses of glucocorticoids, typically quite high doses over time.

Look, it's -- and that was over a decade ago where that approval first happened. So I think people feel it's high time to think about additional drugs that could be used to good purpose in this indication, particularly one as highly differentiated as avacopan. And remember, everything we do with avacopan is really quite different than what's done with glucocorticoid effects or cyclophosphamide effects or prednisone -- I'm sorry, or rituximab. This is something new and could be, again, a very powerful added tool to the arsenal. So I don't think we are really modifying our position very much at all.

Your next question is from Dae Gon Ha with Stifel.

This is Dae Gon from Stifel. I guess just going back to the avacopan story on ANCA, I don't know if you can actually answer this question, but I'm just not very familiar with the process. So with the PDUFA extension, can you speak to the frequency of dialogue that can still happen between you and the FDA and whether or not in those discussions, is it purely limited to you and the FDA? Or can you actually get some KOL participation, to your point, to try and provide a little bit more context around the clinical need and the merits of the drug?

And then a follow-up is going back to the safety data that I'm assuming has been submitted as part of your supplement, the data cutoff has been 28 weeks and 12 weeks for AURORA and ACCOLADE. So I guess what was the most recent data cutoff for the safety database that you supplemented for the agency?

Yes. Dae Gon, thank you. We were able to prioritize the full trial period through the active dosing for AURORA, analyze that data and be able to take that -- those data to the agency. So those go out to 36 weeks. So that's been very helpful. And those data principally reflect what I reported already at top line at 12 weeks, very few kind of SAEs in that trial, both, we believe, reflecting the fact that the drug innately is -- should be fairly safe with very few off-target effects, but also the HS trial population is quite a bit younger, and they have far fewer concomitant medications. And they are, generally speaking, other than this terrible skin ailment, which is not to be diminished in any way, but generally speaking, they are somewhat healthier.

So again, the ANCA patient population is very complicated, has many concomitant medications and generally have many more comorbidities and comortalities to deal with. So yes, we were able to give longer safety data from AURORA. We prioritized that analysis, brought that forward to the agency. I believe we were limited to what we had before in C3G to the 26 weeks data -- blinded data analysis that we had at the time. But again, those look very favorable. That was a somewhat smaller trial, of course, but AURORA had many subjects in it.

So with respect to the -- how the conversations progressed and the nature of those, in a nutshell, obviously, the FDA is in the driver's seat. They tell us what they want to know, when they want to know it, and we respond as best we can. The FDA, I'm sure, and I won't speak for them, but they can avail themselves of any number of experts. To the extent that we bring other voices to the table, again, there's somewhat -- that's somewhat more constrained but not impossible. And I won't say anything beyond that, and we've availed ourselves, I hope and I believe, of every appropriate opportunity to bring additional analysis and expertise to the discussion.

Your next question is from Ted Tenthoff with Piper Sandler.

Great. And not to keep going over this, but have you had additional interaction with the FDA? Or was it simply the data submission and their communication that had meant a major amendment and would require extension?

Thank you, Ted. Again, I'll just generally say the agency can ask for additional information through their process right up to the day of the PDUFA. So without going in any more detail, I would merely say that even beyond our amendment, there's been information exchange through channels that I think are important to the process. But again, I want to respect the FDA's process here, so I won't say much more. I won't say any more than that about the details.

Understood. That's very clear, and I appreciate that. And wishing you the best of luck on that. And then with respect to lupus, what are sort of the gating factors to initiating that study? And has there been any kind of learnings as a result of either incremental data or the interaction with the FDA about how to design that study?

Right. Thank you, Ted. So lupus nephritis, as I understand it, will like -- will go into the same division as ANCA-associated vasculitis, being categorized, among other things, as a rheumatological disorder. So we wanted to respect the division's process with ANCA vasculitis and not at this point create any additional distraction with lupus nephritis. That's why we're holding back, and that's really the principal gating [factor].

Your next question is from Ed White with H.C. Wainwright.

The first question is on HS. Is this similar to C3G that you haven't requested the FDA meeting yet? Or have you already requested it but won't be moving forward until after the PDUFA date?

I would -- again, I want to not go into too many details about regulatory interactions, Ed, with respect -- I would say, again, we will hope to be able to move very rapidly once we have clarity on October 7. That's not to say that there are no interactions with various parts of the FDA on hidradenitis suppurativa because we think it's a super important area, and there's a number of things that we would like to achieve and clarify with the agency.

But again, I think the path there is fairly straightforward because the ability to be very much different than what's gone before in the limited regulatory precedence that the agency is -- to our mind, there's not a ton of degrees of reasonable variation on the theme. So there's -- although there's been learnings since the PIONEER trials, which are the sole trials that led to the approval of the one drug, Humira, for hidradenitis suppurativa, the big parameters around endpoints and so on don't seem to have changed very much.

So we are proceeding, I think, in a very straightforward and thorough fashion. But again, we will wait for clarity around ANCA vasculitis and avacopan prior to putting any new initiatives in place. But I'll certainly be happy to give you a lot more details after October 7.

Our last question is from Yanan Zhu with Wells Fargo Securities.

Tom, Susan, have you had any additional data submission since the major amendment? So that's the first question. And also, could you review the possible outcomes at the PDUFA date? Would there be a possibility for an approval in a subset of patients, for example?

So yes, these questions about additional data, I will stress that the amount of information we put in that was adjudged by the FDA to be in a major amendment was considerable. So we try to be very comprehensive and address the agency's concerns that arose that became apparent to us on the AdCom. We added additional data, tables, figures and listings. I would say that we did a very comprehensive job on -- in what was, again, announced as a major amendment at the agency's discussion on July 6. So suffice it to say, I believe there's sufficient material in the hands of the agency.

So I'm not -- I don't think I'll comment too much at all on -- there's always a possibility that agency could -- decides in their own -- based on their own evaluation, how they want to label the drug. So again, we'll just leave that to their judgment and further discussions potentially. But I don't -- we did a study with a predetermined primary endpoint. We delivered the data on that endpoint. We believe the endpoint was successfully achieved. So I think that a label that generally reflects what we trialed in ADVOCATE would be a reasonable thing. So let's again defer any discussion around the details of that.

Generally, on October 7, the outcomes will either be -- as you mentioned, we'll get a label of some definition or we won't. So I believe -- we're certainly planning. We've always been planning because we think the strength of the evidence is in favor of the data and patient needs, so that's what we're planning for. And we'll go from that point onward.

Got it, Tom. That's very helpful. A quick follow-up with regard to your sales force. Could you share what -- to what extent you built out your sales force prior to the AdCom meeting? And has there been any reduction of the sales force to date?

Very good questions. We made considerable investment prior to the AdCom meeting in building on our sales force, fully intending to be ready to launch the drug on the original PDUFA target date of July 7 and shortly thereafter launching the drug. So we did, I think, an excellent job in amassing not just sales representatives but also medical science liaisons in the appropriate ratio to be ready to launch the drug.

We've suffered very little attrition to that force since then. We're using the expert time to do additional disease education and, among other important things, to ensure an even better launch given the extra time. So we have an excellent commercial force, an excellent commercial organization. And I'm very pleased to say that they are getting more ready by the day. And we believe fundamentally that, that was a good investment to make prior to May 6, prior to July 7 and a good investment to keep making through October 7. So we'll be ready. We'll be very, very ready.

We have a follow-up question from Ed White with H.C. Wainwright.

Yes. Seems like I got cut off there prior to my second question.

Not intentionally, Ed.

No, I'm sure it wasn't, Tom. So just a question on CCX559. I know it's early in the initiation of the study, but I'm just wondering if you have any thoughts on when we can see data there or any update on the number of patients enrolled.

And has there been any impact or do you expect any impact on the study due to the Delta variant? I know you worked very diligently through the first 18 months of the pandemic to enroll patients in your various studies. I'm just wondering if there's any -- if you're seeing anything from the Delta variant and what learnings from the last 18 months you can put forward to perhaps alleviate any concerns over the Delta variant?

Yes. Ed, well, I could -- I have so many thoughts on this topic, Ed, but I'll try to constrain myself and be very succinct here. So with the CCX559 program, in fact, our first sites, we worked very hard to get them open in Australia for a variety of pragmatic and other reasons. And Australia has got a great reputation for doing wonderful work in early oncology studies and later oncology studies as well. So we got those sites all up and running, and we were right on plan. We then -- and then Australia went into lockdown because of the very thing you're discussing. So we were ready to dose essentially when they went into a monthlong lockdown in New South Wales.

So while we got through that and eventually got another -- we started first-in-human dosing in another state in Australia that wasn't locked down, it has had already an effect. Now we hope we can limit that effect. And of course, with these cancer patients, these are folks with fairly advanced cancer, yes, they don't really have a choice. They need to be in the clinic one way or the other. They are happy to engage in a trial, especially a trial with this kind of rationale.

So I'm hoping it won't slow us down to months -- too much rather. But I'm going to defer when we're going to start talking about data until I have a little bit better handle on that myself. But I would -- I'm very keen to get through at least this first step and report to the community what we know even at an early stage because I think we have an excellent compound, beautiful pharmacokinetics in animal models. And I think early data, again, without going into the details, is supportive of that. This is really going to be a good-looking program, in my opinion. We'll just have to see how it continues to progress. But my commitment to you is as soon as we have meaningful data, we're going to start talking about it to this community.

Overall, Delta is going to be a problem. The early -- for clinical trials. I think that's just a fact. There's hesitancy of sites to even engage in discussion about initiation of new trials. And although last year, we and others in the whole industry were very happy about how we seemed to be managing through the initial COVID crisis, quite frankly, longer-term studies and endpoints and follow-on visits and all that stuff, it really is going to affect in the long term how these studies are going to pan out. So I think we've got a challenge ahead in our industry, and we're certainly thinking about it very seriously here at ChemoCentryx. But it's going to have an effect. There's no question about that.

That concludes the question-and-answer for today. I will now turn the conference back to Dr. Tom Schall for closing remarks.

Thank you very much. I appreciate the time that everyone has spent with us this afternoon and all the insightful questions. And I very much look forward to updating you in the not-too-distant future. So thanks very much. Have a great afternoon and a great evening. You may disconnect now. Bye-bye.

Ladies and gentlemen, this concludes today's conference call. Thank you for joining. You may now disconnect. Stay safe and well.