Enanta Pharmaceuticals, inc (ENTA) Q3 2021 Earnings Call Transcript

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Enanta Pharmaceuticals, inc (ENTA -1.75%)
Q3 2021 Earnings Call
Aug 5, 2021, 4:30 p.m. ET

Contents:

• Prepared Remarks
• Questions and Answers
• Call Participants

Prepared Remarks:

Operator

Good afternoon, and welcome to Enanta Pharmaceuticals Fiscal Third Quarter 2021 Financial Results Conference Call. [Operator Instructions]

I would now like to turn the call over to Jennifer Viera, Investor Relations. Please go ahead.

Jennifer Viera -- Head of Investor Relations

Thank you, operator, and thanks to everyone for for joining us this afternoon. The news release with our fiscal third quarter financial results was issued this afternoon and is available on our website. On the call today is Dr. Lly Luly, President and Chief Executive Officer; Paul Mellett, our Chief Financial Officer; and other members of Enanta's senior management team. Before we begin with our formal remarks, we want to remind you that we will be making forward-looking statements, which may include our plans and expectations with respect to our research and development pipeline and financial projections, all of which involve certain assumptions and risks beyond our control that could cause our actual developments and results to differ materially from those statements. A description of these risks is in our most recent Form 10-Q and other periodic reports filed with the SEC. Enanta does not undertake any obligation to update any forward-looking statements made during this call.

With that, I'd now like to turn the call over to Dr. Jay Luly. Jay?

Jay R. Luly -- President, Chief Executive Officer and Director

Thank you, Jennifer, and good afternoon, everyone. Our fiscal third quarter was marked by the achievement of several important milestones and continued progress across our clinical portfolio. Starting with COVID-19, we are pleased to announce that we have identified a clinical development candidate, EDP-235, an oral protease inhibitor specifically designed to treat SARS-CoV-2 infection and potentially other coronavirus infections. We are eager to progress this program into the clinic and are on track to initiate a Phase I study of EDP-235 early next year. In hepatitis B, we are excited by the progress we've made with EDP-514 and EDP-721, which we are developing as part of an all-oral combination regimen to achieve a functional cure.

We expect to begin dosing in our Phase I study of EDP-721, a novel oral HBV RNA destabilizer, this month. Additionally, this quarter, we announced positive Phase Ib 28-day data for our core inhibitor EDP-514 in two important patient populations: chronic HBV patients who have a high viral load, whom we refer to as Virena patients; and chronic HBV patients who are on a treatment with a nucleoside reverse transcriptase inhibitor, whom we referred to as nuc-suppressed patients. The significant progress we've made across our HBV program brings us closer to our goal of developing an all-oral functional cure for patients. Moving to the rest of our pipeline. We have three ongoing Phase II clinical studies investigating 938 for respiratory syncytial virus, or RSV, and two ongoing clinical studies for candidates to treat nonalcoholic steatohepatitis, or NASH. In addition to our clinical programs, we continued to progress our respiratory virus discovery initiatives to identify an L inhibitor for RSV and an inhibitor for human metapneumovirus, or HMPV.

With that, I'd like to dive deeper into each of the programs that make up our robust pipeline, beginning with SARS-CoV-2. We are pleased to have selected EDP-235, a direct-acting antiviral oral protease inhibitor, as our clinical development candidate for SARS-CoV-2 and plan to initiate a clinical study early next year. As SARS-CoV-2 continues to mutate and new variants arise, we believe there remains a need for a potent oral treatment that is specifically designed to inhibit replication of this virus and are excited to progress this program. While vaccines and antibody therapeutics and development today target the viral spike protein, EDP-235 has been specifically designed to target a conserved region in the active site of an enzyme essential for SARS-CoV-2 replication. So we do not expect mutations in the spike protein to significantly affect the activity of our candidate. Further, EDP-235 potently and selectively inhibits SARS-CoV-2 replication in multiple cellular models, including primary human airway epithelial cells were demonstrated in EC90 of 33 nymor.

Importantly, activity is retained against currently circulating SARS-CoV-2 variants, and a high barrier to resistance has been observed. Additionally, EDP-235 demonstrates preclinical properties supportive of once-daily oral dosing. If we are successful, our vision is starting early diagnosis of COVID-19, followed by outpatient treatment with a highly potent and targeted oral therapy. Shifting gears to HBV. We recently announced preliminary data from the first 2-dose cohorts of our Phase Ib study of EDP-514 in virenic chronic HBV patients, which further demonstrated the compound safety and tolerability as well as its ability to reduce HBV DNA levels significantly over the 28-day dosing period. To briefly recap the data, 16 patients were randomized to receive daily doses of either 200 milligrams or 400 milligrams of EDP-514 or placebo for 28 days. Mean reductions in HBV DNA of 2.9, 3.3 and 0. two logs were observed in the 200-milligram, 400-milligram and placebo groups, respectively, with a maximum reduction of 4.2 logs in the 400-milligram group versus 0.5 log in the placebo group. four patients receiving EDP-514 had HPV DNA below the lower level of quantitation compared to none who received placebo.

Additionally, mean reductions in HBV RNA of 2.9, 2.4 and 0.3 logs were observed in the 200-milligram, 400-milligram and placebo groups, respectively, with a maximum reduction of 4.8 logs with EDP-514 versus 1.9 logs with placebo. HBV RNA was undetectable at day 28 in eight patients in the 514 group as compared to none in placebo. Further, EDP-514 was trying to be safe and well tolerated in this patient population. This study provides important clinical evidence of EDP-514's safety profile as well as kinetics of viral inhibition when used as a single agent over 28 days and is a significant advance in our efforts to deliver an all-oral functional cure for hepatitis B. Building on that success, we also recently reported positive 28-day data from the first two cohorts, 200 and 400 milligrams, of our Phase Ib study of EDP-514 in nuc-suppressed chronic HBV patients. Importantly, these 28-day data demonstrate that EDP-514, when combined with a NUC, was safe and well tolerated. Additionally, EDP-514 demonstrated reductions in HBV RNA, along with the pharmacokinetic profile supportive of once-daily dosing. Together, these data support development of EDP-514 in combination with a NUC as a 2-drug foundation on which to add other agents such as EDP-721.

Such an all-oral combination therapy is a differentiated approach that could potentially lead to a functional cure for patients with chronic HBV. To that end, we expect to begin dosing in the Phase I study of EDP-721, our oral HBV RNA destabilizer, this month. Our enthusiasm for the development of EDP-721 is based in part on the preclinical data we presented at EASL in June. In vitro, EDP-721, potently reduced HBV surface antigen with pan-genotypic HBV activity through its selective inhibition of PAP-D5 and PAP-D7. Moreover, EDP-721 showed additive to synergistic antiviral activity in vitro when combined with NUCs or HBV core inhibitors such as EDP-514. Oral administration of EDP-721 in the AAV HBV mouse model also demonstrated favorable efficacy characteristics, inducing up to a 3-log drop in the HBV surface antigen. These preclinical data are particularly -- because effective reduction of HBV surface antigen has presented a substantial challenge to achieving long-term HBV viral clearance. Moving to RSV. EDP-938, the only N inhibitor in advanced clinical development today, is currently being evaluated in three ongoing Phase II studies.

As a reminder, RSV is a severe respiratory infection associated with significant morbidity and mortality, not only in infants, but in the elderly and in immune-compromised adults as well. There is no safe and effective treatment for this viral infection. So we previously mentioned, RSV like flu did not emerge during the most recent Northern and Southern Hemisphere seasons due to COVID-19 mitigation measures. However, where social distancing measures have subsided, RSV has begun to reemerge and has already been observed with recent spikes of pediatric RSV cases in Australia and parts of the United States. In fact, in June, the Centers for Disease Control and Prevention issued a health advisory to notify clinicians and caregivers about increased inter-seasonal RSV activity across parts of the Southern United States. With this in mind, we have continued to establish additional trial sites in North America Europe, Asia Pacific and the Southern Hemisphere.

These efforts will be key to our recruitment and our RSV clinical program, which includes RSVP, our Phase IIb study evaluating EDP-938 in adults with a community-acquired infection; RSVTx, a Phase IIb study evaluating 938 in adult hematopoietic cell transplant recipients; and RSVPs, a Phase II study in pediatric RSV patients. Given that the recent reemergence of RSV is not following any normal seasonal pattern, it's very difficult to predict how significant or sustained the new incidents of RSV will be moving forward. Nonetheless, we are more hopeful that we'll be able to complete enrollment in the RSVP study during the Northern Hemisphere winter season as long as there are no renewed social distancing trends. Assuming this enrollment occurs, we would expect the data in the first half of 2022. As for RSVTx and RSVPs, which were initiated more recently than RSVP, we will continue to monitor the situation and update as appropriate.

Beyond EDP-938, our other two respiratory virus discovery initiatives targeting RSV and human metapneumovirus are also showing promising promise during lead optimization. RSV L inhibitors are another drug class that block viral replication and could potentially be used alone or in combination with other agents such as 938 to possibly broaden the treatment window or addressable patient population. As for HMPV, we believe this initiative is a natural adjacency for us as the virus is very similar to RSV. HPV has been shown to have worldwide circulation with nearly universal infection by age 5. The notes at highest risk include elderly, adults with underlying pulmonary disease and those who are immune compromised. By year-end, we hope to nominate another clinical candidate from either our HMPV or RSV L inhibitor initiatives.

Finally, I'll end with the summary of our work in NASH, a liver disease with a significant unmet need, where we are conducting clinical studies of two FXR agonists, EDP-305 and EDP-297. Recruitment and dosing in ARGON-2, our Phase IIb study of EDP-305 in patients with biopsy-proven NASH with fibrosis, is progressing. Later this quarter, we'll have a planned internal interim analysis based on 12 weeks of treatment in a subset of patients from this study. Also later this quarter, we expect to report data from a Phase I first-in-human study of our follow-on FXR agonist candidate, EDP-297. We anticipate that the combined data from this Phase I study and the EDP-305 internal interim analysis will enable us to determine next steps such as potential partnering and combination approaches for our NASH program. Before moving to our financials, I'd like to highlight our upcoming milestones, which we believe position us for a strong remainder of the year.

For COVID-19, we've nominated EDP-235 as our lead oral protease inhibitor and expect to initiate a clinical study in early 2022. In HBV, we plan to dose the first patient in the Phase I clinical study of EDP-721 this month. In NASH, we look forward to preliminary data from the Phase I study of EDP-297 later this quarter and determination of next steps for our NASH program following an internal interim analysis of ARGON-2. Finally, we continue to be excited about the early prospects coming out of our two other respiratory virology discovery initiatives and are eager to name a new clinical development candidate for RSV or human metapneumovirus by year-end. I'd also like to take a moment to thank Dr. Nathalie Adda, Senior Vice President and Chief Medical Officer, for her dedication to the company over the last six years, during which she built and led the clinical development and regulatory team and helped advance our pipeline candidates. As announced, her retirement is planned for February, and we wish her the best. We're thankful that she is staying with us in a consulting capacity thereafter.

With that, I'll stop here and turn the call over to Paul to discuss our financials for the quarter. Paul?

Paul J. Mellett -- Senior Vice President, Finance & Administration and Chief Financial Officer

Thank you, Jay. I'd like to remind everyone that Enanta reports on a September 30 fiscal year schedule. Today, we are reporting results for our third quarter ended June 30, 2021. For the quarter, total revenue was $21.6 million and consisted of royalty revenue earned on AbbVie's global MAVYRET net product sales. This compares to total revenue of $18.7 million for the same period in 2020. The increase in royalty revenue compared to the same period last year was driven by higher HCV product sales as treated patient volumes have increased compared to the third quarter of last year when the COVID-19 pandemic began. HCV product sales continue to remain below pre-COVID levels as a residual impact from the pandemic continues. Royalty revenue was calculated on 50% of MAVYRET sales at a royalty rate for the quarter of 10%, after adjustments for certain contractual discounts, rebates and set-offs, which are now approximately 2% of AbbVie's total reported HCV product sales.

You can review our royalty tier schedule in our 2020 Form 10-K. Moving on to our expenses. For the three months ended June 30, 2021, research and development expenses totaled $47 million compared to $34.7 million for the same period in 2020. The increase was primarily due to the timing of our clinical trials year-over-year. General and administrative expense for the quarter was $8. four million compared to $6.8 million for the same period in 2020. The increase was due to an increase in head count and compensation expense. Enanta recorded an income tax benefit of $9.4 million for the three months ended June 30, 2021, compared to an income tax benefit of $7.1 million for the same period of 2020. These income tax benefits were due to the provisions of the CARES Act of 2020, which enables the company, through fiscal 2021, to carry back its projected current year tax loss to offset taxable income in prior years.

Net loss for the three months ended June 30, 2021, was $24 million or a loss of $1.19 per diluted common share compared to a net loss of $14.3 million or a loss of $0.71 per diluted common share for the corresponding period in 2020. And we ended the quarter with approximately $373 million in cash and marketable securities. We expect that our current cash, cash equivalents and short-term and long-term marketable cash and marketable securities. We expect that our current cash, cash equivalents and short-term and long-term marketable securities as well as our ongoing royalty revenue will continue to be sufficient to meet the anticipated cash requirements of our existing business and development programs for at least the next two years. Further financial details are available in our press release and will be available in our quarterly report on Form 10-K, when filed.

I'd now like to turn the call back to the operator and open up the lines for questions. Operator?

Questions and Answers:

Operator

[Operator Instructions] Your first question will come from Brian Skorney with Baird. Please proceed.

Brian Skorney -- Baird -- Analyst

Hi. Good afternoon. Thanks so much for taking the question. I really want to talk about EDP-938, and I was wondering if you could kind of give us some compare and contrast on the potency of the PDS inhibitor with remdesivir and maybe Pfizer's PI. And can you do effective serial passage studies with SARS-CoV-2 models? And can you comment at all on what sort of resistance you can induce? And then just on the safety front, what sort of room do you have on selectivity index before you start hitting some of the human proteases and seeing cytotoxin? That's it.

Jay R. Luly -- President, Chief Executive Officer and Director

Hi Brian, this is Jay. So I think you meant EDP-235 not EDP-938.

Brian Skorney -- Baird -- Analyst

Oh, sorry, yes.

Jay R. Luly -- President, Chief Executive Officer and Director

So anyway, EDP-235, the SARS-CoV-2 protease inhibitor that we announced today, serial passage. I mean, we don't have the live SARS-CoV-2 virus in-house. So we rely on external providers for some of those kinds of studies. But we do, do extensive worth looking in resistance in-house but we use model coronas for that work. And so to that end, the profile that we've generated so far internally, it's very, very nice. And so we're excited by not only that net attribute, but obviously also the the potency that we have there. I think when you look at a candidate, which way we look at a candidate versus others that are out there, just even where we put the the mark on the map for what we're trying to hit, we obviously want to drill down on potency and look at that in lots of different ways.

We've reported good data in primary human airway epithelial cells, which is a great way to look. We also look at activity against variants. And we're pleased with the profile that we've seen there, talked about the serial passages that we've done and then getting on to safety. I think we've -- we look -- we do sort of extensive safety work prior to taking any of our candidates that we feel very comfortable with the safety package that we've put together for this candidate. So I -- given the potency and the wide windows, we don't expect any sort of complications going into our clinical studies with this molecule. But looking beyond that, these are sort of the meat and potato things that we pushed it and looked at even further. As you know, we're always looking at tissue targeting and social distribution, whether it's with our FXR, whether it's with or hepatitis drugs.

And SARS-CoV-2 exceptionally, we saw very good tissue distribution and looked at lung levels and rodents, very pleased with that profile. And also having surveyed PK across multiple different species, we feel pretty confident that this is a QD-dosing drug. So it's really the aggregate of all these things put together. You can put a punch those together and check 9 of it, but we weren't done until we checked every box we were aiming to do in this candidate. I think the other sort of exciting aspect of this is we have seeing activity against other coronaviruses with this as well. So there's the possibility that we could go beyond SARS-CoV-2 here and think about readiness for other pandemic viruses or the coronaviruses. So all in, it's a very exciting candidate. And as we've mentioned, we're on track to resume clinical studies early next year.

Brian Skorney -- Baird -- Analyst

Great. Thanks for taking my question Jay.

Jay R. Luly -- President, Chief Executive Officer and Director

You're welcome.

Operator

Your next question will come from Yasmeen Rahimi with Piper Sandler. Please proceed.

Unidentified Participant

Hi. Good evening. This is [Indecipherable] on for Yas. A couple of questions. First is for 721, should we expect to see the 800-milligram cohort data at ASLD. And then based upon your internal PKPD modeling work, how much additional HBV DNA knockdown benefit do you expect to see over the reported 200- and 400-milligram doses?

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. I think you've got a compound number mixed up, too. I think you said EDP-721, and I think you were referring to EDP-514, the core...

Unidentified Participant

Yes. sorry. Sorry, yes.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. I know we have a lot of molecules to keep track of it. So the -- with regards to 514, the 200- and 400-milligram doses, whether we were looking in nuc-suppressed patients or viremic patients, both of them showed a very good performance, not only in terms of safety and PK, which is one of the main things we were looking for, but also in the case of the nuc-suppressed, you can only want to make sure that our molecule behaved well with a NUC, right, because we wanted to set the foundation of a 2-drug combo on which to add the other molecule you mentioned, 721, to make an all-oral triple. So I think we got -- based on the virology that we saw at the 200 and 400, when you look at DNA or RNA, whether you look at the population or the other, we saw good safety and good virology as we would have expected in each of these different patient populations. And it definitely sets the stage for moving ahead. I think the 800, what will we see there on top of that? We saw such significant exposure at 200 and 400. And it's not clear that any more exposure will give you any more benefit. But of course, we'll pull that data in and see it, and we'll put it out at whatever the next appropriate sort of major scientific conferences to do that at. So stay tuned on that front. But again, I think we've seen what we need to see already to know that 514 has a great antiviral effect a great safety and tolerability profile to assume to date in HBV patients up to 28 days and a good 2-drug foundation with the meet to set the stage for a triple with EDP-721.

Unidentified Participant

Okay. Great. I had one follow-up question. So for 235, what gating factors are remaining? Where are you guys in terms of regulatory pathway before you initiate the Phase I trial in 2022?

Jay R. Luly -- President, Chief Executive Officer and Director

Yes, I'd say that, I mean, all the IND-enabling studies are done. So we're packaging that sort of stuff at. We're procuring drug supply. We're getting all those kinds of things in terms of readiness as we prepare for the the Phase I study, but it's just sort of routine stuff at this point.

Unidentified Participant

Great. Thanks for taking the question.

Operator

Your next question will come from Brian Abrahams with RBC Capital Markets. Please proceed.

Brian Skorney -- Baird -- Analyst

Hi guys. Congrats on the progress. Thanks for taking my question. An my congratulations and best of luck to Dr. Adonis retirement. First question on 235, maybe a bigger picture question. I was wondering if you could maybe talk about how you're thinking about next steps here, just Phase I and beyond for the program, what you think the clinical path might look like. And is this something where you might expect a PI alone to be adequate? Or do you think this could be more akin to HIV or hep C, where you'd want to combine this with other classes of direct-acting antivirals like NUCs?

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. It's a good question, Brian. We -- the answer is nobody really knows. But that said, we're talking about an acute infection here. So I think we're pretty encouraged that a single agent could be enough. Now obviously, when we set up this program at the beginning of the pandemic, we didn't work just on this mechanism, but we have been and continue to be working on other mechanisms just because you never know what could happen here down the road with regards to variants or anything else. But from what we see, I think we would be very encouraged to take a produce and see an impact on, hopefully, viral aids and sometimes very quickly with these mechanism sort of or sort of trying through DAA mechanisms. And we certainly don't know yet that we would need to go in with combination therapy as you might expect to do in hepatitis C or certainly in hepatitis B. So as you know, with RSV, we're looking at short-term treatment with our RSV drug as a moderate agent. But again, for that program, just like with SARS-CoV-2, we're going to take multiple approaches just because at the end, if we can come up with an even better approach on the line, that would be great if combinations as needed down the line.

We want to be in the position to have potentially multiple quality assets. And that's why we continue exploring an RSV now in multiple Phase III studies with a very promising agent. Can it help us, for example, get into different patient populations that we might not otherwise be able to get into, but it allow us to treat more severe patients or broaden the treatment window, these are all questions that we can ask in due course. But one of the things, just from a paradigm in general, that we thought about RSV, sort of the holy grail here is early diagnosis and rapid treatment. You've heard me talk about that concept now for multiple years in connection with RSV. We believe it plays in the metapneumovirus.

We were talking about that just before the pandemic launched. And now with SARS-CoV-2, we think that possibly tucks in there as well. So again, this is -- we've been stating this sort of approach and goal for a long time now with different viruses. And I think a lot of people know that the sort of the vaccine visibility has run a course for a while now. People are starting to think about, wonder about and worry about the lack of therapeutics. And to that end, I think a lot of people are thinking it would be wonderful to have something that if you are symptomatic, you go to CVS, you get a swab, you're positive and you get treated as an outpatient with an easy-to-use, safe oral drug that you can just go home, lock that viral load down, start the shedding, get back to work. So that's among the things that we're thinking about. So hope that helps.

Brian Skorney -- Baird -- Analyst

Yes. No, that's really helpful, Jay. And then maybe one more on 938. I know you've been continuing to expand and mobilize your sites. I'm curious to what degree you've been able to take advantage of the recent off-cycle RSV spikes. Is there -- I guess how much consistency is there regionally with where these spikes are and where your trial sites are? And are there any changes in the way you might screen or even monitor patients in an off-season RSV surge versus the normal seasonal uptick?

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. We're pretty spread out geographically in the U.S. and globally. You are correct, and I saw your note earlier this week that -- and we've been pointing it out, too, that first starting in the Southern Hemisphere, once summer rolled around in the summer. While we were in winter, it was becoming summer in the Southern Hemisphere and the masks started to drop a little bit in Australia, and they saw that this huge pediatric spike, interseasonal spike. And then we were quietly thinking, well, that could all happen here. And guess what?

It did start to happen. A few weeks ago, the CDC said there has been this big uptick on interseasonal RSV in some spot. It's been in certain Southern parts of the United States where these things sort of pop up. So we've got sites all over the place. And so we have seen some upticks, and that's why we are cautiously optimistic that if trends continue and we go into the winter season here, that we should be able to wrap up the RSVP study this season. And if that's the case, then we would have data in the first half of next year. But what I think we really need to see is are these little interseasonal spikes is going to tamp down? Are they going to tamp down and then come roaring back in the fall and again in the one, two months when RSV is normally prevalent.

I mean is every expectation that -- and you start to hear about it on the news. The other -- yet another respiratory virus that people should have on their minds, though we don't have enough to think about with COVID. But we're starting to hear more and more that awareness for RSV is coming back. The testing is coming back. The CDC has recommended that just because somebody has something, don't assume that they have SARS. And if they're SARS-CoV-2 negative, get tested for RSV anyway. So this is the way we're going to start to figure out where these real patterns are. But we've got our catches mitt on, and we've got lots of sites around. And so as patients come in, we'll be ready to grab them.

Brian Skorney -- Baird -- Analyst

Great. Thanks again.

Jay R. Luly -- President, Chief Executive Officer and Director

You're welcome.

Operator

Your next question will come from Roy Buchanan with JMP Securities. Please proceed.

Roy Buchanan -- JMP Securities -- Analyst

Hi great. Thanks for taking the question. Had a couple on 235, I guess. So the structure of Pfizer's lead oral inhibitors out there. I'm just curious if you guys did any side-by-side comparisons in view of potential differences between assays. And if you have a side-by-side comparison of the potency? And then can you tell us if 235 is covalent? Is it reversible? And a follow-up.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. No, I know exactly the kinds of questions you're asking. It's not the kind of questions I usually answer until we're ready to answer them. But it's fair to assume that we do extensive benchmarking across all kinds of parameters with every molecule that we can lay our hands on. And we've done that with 235.

Roy Buchanan -- JMP Securities -- Analyst

Okay. And then kind of along the same lines. Are you going to present or publish either preclinical or chemical data before the Phase I results? Or are the Phase I result is going to be the first we're going to see data?

Jay R. Luly -- President, Chief Executive Officer and Director

So there might be -- we'll see -- you're talking about putting up preclinical data of some sort.

Roy Buchanan -- JMP Securities -- Analyst

Right, as opposed to paper, right.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. Yes, we're working on that strategy internally. I think on the one hand, it's deciding to put these kinds of bits of information out in various public fora, but we're really focused on mobilizing and pushing ahead to get ourselves into the clinic and then ultimately get into clinical -- later-stage clinical studies as fast as we can. So that the data will come out in de course.

Roy Buchanan -- JMP Securities -- Analyst

Okay. Got it. And I had a few on 721. Looking at the clinicaltrials.gov record, I see the one site in New Zealand. I guess that there are going to be additional sites added. And I didn't see any breakdown of the number of patients in the viremic and the nuc-suppressed groups. Can you give us a sense of what that target breakdown is, if there is one? And then I have a few more questions.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. So right now, we're -- as we sort of had in our prepared remarks and the release, the 721 study has been initiated. We're screening now. We're expecting to dose this month. So let us do the study, and we'll report more details on our clinical trial design on how we're going to put put this triple combo together, etc, etc. We'll have more details on that at a later time.

Roy Buchanan -- JMP Securities -- Analyst

Okay. Fair enough. You probably won't answer my other questions either, but I didn't see you have the combo with 514 in the trial design. So that's exciting. All right. I guess I'll ask one last question on a different topic. So NASH, not the current programs, but you guys have talked about a novel mechanism for some time. I'm just curious when you might disclose the target or the pathway, just any news there? Thanks.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. So we obviously haven't prepared to disclose that target and program this quarter. But I think it's fair to say we've just got a lot in NASH all coming together here in the next little bit. And I think this quarter will be really interesting for us as we're pulling in our internal interim read on ARGON-2. We'll have Phase I data on our other FXR agonist, EDP-721. With the ARGON-2 IA, our hope is to figure out what are the appropriate doses that we can peel off then and entertain a combination studies with perhaps in the context of a partnership, etc, etc. So suffice it to say, we're thinking about this quarter in NASH and a big picture sort of way.

Even if we were thinking of ultimately teaming up in some sort of a partnership, would we do that even with our earlier stage program? These are questions that we haven't completely sorted out, but we're thinking through right now. But with regards to your very specific question about what is the target, we're not [Technical Issues] talk a little bit about as we prepare for RSVP, what specifically we should be looking for in the data to -- and to make an assessment.

Roy Buchanan -- JMP Securities -- Analyst

Sure. Maybe I'll pull this question over to Nathalie to comment on further. But maybe I'll just go and preface it by saying you recall our human challenge study where human volunteers were infected with the virus. You wait around. You constantly monitor their viral loads. And once the viral load puts a certain threshold, you began dosing. And when the people begin to receive drug, they were also symptomatic with at least a symptom of sorts. And what we saw was, number one, a very nice set of viral kinetics as one of the key things we were looking for in that study, very different than placebo.

As soon as we started dosing drug, the course of the infection completely changed. People with placebo continued to get worse, and people on drug got better. That was -- you could look at that in the form of viral loads. You could look at it in parallel with the same time course with people's symptoms. I think in the outpatient setting, we're not able to get the same frequency of viral loads. I think we were doing -- when they're in the challenge study, you're able to take swabs twice a day. I think we were doing over the course of the whole study. That's just not feasible in an outpatient study. So but it's not to say that we won't get any virology. But what we are tracking is at least symptoms. Some have sometimes, some we'll have virology, as I said of readouts. But Nathalie, do you want to comment any further?

Nathalie Adda -- Senior Vice President and Chief Medical Officer

Sure. Thank you for your question. So maybe just to add to what Jay was saying. I think there's -- I would make a few additions to that. Obviously, we want to confirm the selected dose, the 800 milligrams that was assessed in the challenge study. There were 600 milligrams, but through this year, we had to increase it. So I think it's going to be important to at least have a good assessment and confirm that our selected dose is the one for the patient savings. That's one thing. And we'll confirm then to important primary endpoint, which is the [Indecipherable].

We want, obviously, to get out of that study, understanding that the translation from the challenge study in a more, I would say, artificial savings is confirmed in an outpatient saving. And we want to show that as you treat patients within a very short window, that we can allow the patient to not progress to a more severe disease, and they will be translating into more symptom, this is where it's going to be for to look at our primary endpoints. We are well colored our study to be able to do that without. We believe that the effect size was assessed for the 4 of the study is appropriate, and then we benchmark that to the challenge study, but we were very conservative when we for our MP spend. So I think we will be able to confirm the translation on the challenge to the allocation state.

Roy Buchanan -- JMP Securities -- Analyst

Okay. Great. And then, Jay, if you could talk a little bit about kind of your different, I guess, potential path we could take with the NASH program and what you're looking from the data kind of go down those different paths? What -- maybe you can summarize how you're thinking about it ahead of data coming out. Thanks.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. Well, we've always -- for years now, I think, actually, we've said that with regards to NASH, we don't aspire to be a commercial stage NASH company. We don't aspire to be a Phase III NASH company. Instead, we want to do Phase II work, get appropriate Phase II data point and then team up with another party. And so I think that's really how we're thinking about it, the focus on that. I think ultimately, FX in the right doses can still make a big impact, I think, in the form of combinations. And so we'll be -- again, that's why the IA that we're going to be getting here soon is really appropriate. You recall from our ARGON-1 study, we looked at one milligram and 2.5 milligrams. We saw unacceptable pruritus at 2. 5. It's sort of like an intercept, now looked at 10 and 25, right?

We looked at one and 2.5. And so ARGON-2 now is, as you know, and I know we've had discussions on this in the past, ARGON-2 has gone down between those two doses, just to see, is there another dose other than the one milligram where we did see significant target engagement? So even at one milligram, we saw it, but we we felt like we could be leaving some efficacy on the table. So can we tweak it a little further, extract more efficacy without pushing pruritus button, whatever mysterious button that is. And so that's what we'll get. We're going to get that there. And again, we already know the one milligram. We know the 2.5. We're looking to be it in three nodes point. And that will give us dosing information, again, for which we can peel off and do seek certain combination possibilities. So -- and we would aim to do that in the context of a partnership. Again,

Roy Buchanan -- JMP Securities -- Analyst

Okay. Great. Thank you.

Jay R. Luly -- President, Chief Executive Officer and Director

You're welcome.

Operator

[Operator Instructions] Your next question will come from Jay Olson with Oppenheimer. Please proceed.

Matt -- Oppenheimer -- Analyst

Hi. This is Matt on for Jay. Thanks for taking our question. The first thing I wanted to ask was since HBV is a large global opportunity, what are your thoughts for a potential partnership there, especially ex U.S.? And also since a potential partner would be likely to seek a role in clinical development, at what point would you consider potentially identifying a potential partner in HBV? Thanks.

Jay R. Luly -- President, Chief Executive Officer and Director

Sure. Those are great questions. Well, since actually, we just talked about partnering and NASH, I've also spoken about partnering in HBV. And there is a little bit different than NASH, and that in turn is a little bit different than our human respiratory program. But let's talk about HBV. And I'll contrast it to HCV. When we did our HCV deal with Abbott, which became AbbVie several years ago, we had a protease inhibitor and they had other assets, but neither of us had the combination that we needed to put together to create the all-oral cure. This is a little different. We do have -- possibly anyway, we're assembling the agents that we hope to be sufficient for an all-oral cure, right? We have mixes of standard of care. Everybody sort of gets a NUC for free. That our core inhibitor, we've now put out two good data sets on that, including the 2-drug combination with the NUC. And now we've got 721 getting ready to be dosed here very soon, which will be the third part of that potential all-oral triple.

So I think what we're going to have is, is that enough? And we'll be doing the experiments, clinical trials that will help us sort out whether or not that is enough. We're very excited by the possibility because if we do, it's a highly differentiated product profile with an all-oral therapy. All oral will always win out over a mixture of injectable and oral therapies, all things being equal. And so with the -- now with the advent of 721, which we announced just this year, we announced it in the context of a candidate and the short runway into the clinic and a punitive effect on S antigen reduction, we think we may have all those bits and pieces. So that's the nearer term, right? We'll hopefully be in an all-oral triple trial next year. And if that data looks good, you can start to think about, well, what are the steps beyond that? And that's where you start to think about HBV being such a big global infection. If you look at the U.S., if you look at the EU 5, if you look at Japan, we add them all up, it's a very large market, but it's only a fraction the worldwide unmet need for treating and curing hepatitis B patients who are chronically injected.

And so for global reach and scale, there's -- if you follow with the docs, it's highly likely that we'll have a global commercialization partner. Would we retain co-commercialization opportunity in certain territories? Yes, at least the option to do that. We had that option with two different drugs in our hepatitis C program with AbbVie. We elected not to do co-commercialization. At the time we need to elect to do that, we were -- In one instance, we were a private company. In another instance, maybe even both times we might have been a private company. It's no way we could have even contemplated that. Fast forward and thinking a few years into the future, if we have an all-oral triple, it could be a different set of circumstances for us, and we'll see where we are at that time. But I do believe we're still independent of that, we'll still want to have another partner to help us to maximize this to patients worldwide. Is that helpful?

Matt -- Oppenheimer -- Analyst

Okay. Got it. Yes. That's awesome. Really helpful. And then the last question we had was just on EDP-938. And so for the pediatrics and adult studies that you recently initiated, Just curious what you're hoping to see in the data there also when we could expect to see data and kind of how you're thinking about the market opportunities for each, that would be great.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. Well, peds is the biggest, I'll tell you that. The peds is a very large market. Transplant is a very important market also. I mean, the folks who are immune compromised, if they get an RSV infection, it can just be catastrophic. And so it's a really important other patient population, but pedes is definitely a larger population. Now the transplant study, we just got going at the end of last year in the PED study, we just got going in March. And also, I'll remind you too, in the PED study, the first part of it is really safety and PK. And then the second part of it is when we'll get into other aspects of the RSV infection. But so those things are necessarily tracking behind a study RSVP, which we already had ongoing and partially enrolled. So it's a bit early for us to give any sense of timing on those two studies, are they going to be further out. I think this upcoming season will be very telling in each of them, allow us -- once we get this next season under our belts, I think we'll lever a much better idea where we stand.

Matt -- Oppenheimer -- Analyst

Okay. Got it. That makes sense. Really helpful. Thanks again for taking my question.

Jay R. Luly -- President, Chief Executive Officer and Director

You're welcome.

Zegbeh Jallah -- ROTH Capital Markets -- Analyst

Hi. Thanks for taking my question. Just had a quick one really about your COVID program. I was just wondering if you're considering any unique treatment strategies in light of other drugs being approved or vaccines being approved? I know this is quite different as a treatment, which just wondering because Regeneron did also get their drug approved as a prophylactic after exposure. So I was just wondering if you're thinking about anything unique in terms of when treatment will be delivered.

Jay R. Luly -- President, Chief Executive Officer and Director

Yes. Well, there's -- treatment of any start would be a major milestone. But I do believe you could also consider prophylactic consistent study. So that's among the things that we're thinking about and chewing on, but straightforward treatment is clearly where the most urgent need is right now. So let's assume that we'll do that, and it's true here. I mean the antibodies, I think, that are out there played an important role, particularly early in the pandemic and prior to vaccines. Vaccines have kind of helped an enormous amount. It could obviously be helping even more. But I think ultimately, the missing piece here and the piece that will be durable long term are going to be the small molecule antiviral molecules, a direct-acting antiviral, of which, obviously, 235 is. And there will be multiple generations there to assume that people are going to be out there doing it. I mean when we were going into hep C, Enanta wasn't the first protease inhibitor, but were the best. So -- and even our first protease inhibitor, even though it was better than the prior ones that had been looked at, we came up with an even better one than that later on, which ultimately did become best in class with of glecaprevir. So I think 235 is a very strong entrant. We feel very good about it, and we'll let the data speak.

Zegbeh Jallah -- ROTH Capital Markets -- Analyst

And just a quick follow-up in terms of the dosing. What's the dosing regimen? Or what are you hoping to achieve with that?

Jay R. Luly -- President, Chief Executive Officer and Director

We think we can -- again, we're -- we always aim for QD dosing. Once daily is always best. And we pretty much always have hit that mark. Our preclinical studies suggest that that's likely to be the case here. I mean we usually hit that mark in the clinic because we're very good at modeling that preclinically across multiple different species, and so spent a lot of time sort of engineering that time sort of engineering that attribute as well. And I think people who know this landscape know that it's not necessarily given that you can achieve that. So again, we'll have to prove that in the clinic, but we feel very good about the kinetics that we've seen preclinically. And then beyond that, again, it's an acute infection. We would expect normal people who have generally competent immune systems. We could do a short-term dosing. Probably it wouldn't be unreasonable to assume it's something like a 5-day dosing regimen just like you do in RSV, but we'll see. It could be -- it's going to be short relatively speaking to some protracted dose enlargement.

Zegbeh Jallah -- ROTH Capital Markets -- Analyst

Thanks Jay. Looking forward for more about the program.

Operator

And at this time, there are no further questions. I would now like to turn the call back over to Jennifer Viera for closing remarks.

Jennifer Viera -- Head of Investor Relations

Thank you, everyone, for joining us today. If you have any additional questions, please feel free to contact us by email or call us in the office. Thanks, and have a good night.

Operator

[Operator Closing Remarks]

Duration: 60 minutes

Call participants:

Jennifer Viera -- Head of Investor Relations

Jay R. Luly -- President, Chief Executive Officer and Director

Paul J. Mellett -- Senior Vice President, Finance & Administration and Chief Financial Officer

Nathalie Adda -- Senior Vice President and Chief Medical Officer

Brian Skorney -- Baird -- Analyst

Unidentified Participant

Roy Buchanan -- JMP Securities -- Analyst

Matt -- Oppenheimer -- Analyst

Zegbeh Jallah -- ROTH Capital Markets -- Analyst

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