ENTA

LLM Evaluations

Transcript Summary

Enanta Pharmaceuticals is advancing a robust clinical pipeline focused on oral therapeutics for RSV and chronic inflammatory diseases. The company’s RSV strategy involves two distinct mechanisms: zelicapavir (N-protein inhibitor) and EDP-323 (L-protein inhibitor). Key readouts for the EDP-323 challenge study and the zelicapavir pediatric Phase II (RSVPEDs) are slated for the second half of 2024. Management highlighted that while the adult high-risk RSV study (RSVHR) faces a high statistical bar due to its 50% symptom-reduction powering, directional efficacy would justify Phase III progression. Enanta is also diversifying into immunology, specifically targeting Chronic Spontaneous Urticaria (CSU) with a selective oral KIT inhibitor. A development candidate is expected by Q4 2024, with a second immunology program to be revealed this year. Financially, Enanta reported $17.1 million in quarterly royalty revenue and maintains a strong cash balance of $300 million, extending its operational runway into late 2027. While management remained tight-lipped regarding patent litigation against Pfizer, they provided clear clinical guidance and strategic rationale for their multi-pronged approach to RSV and the expansion into mast-cell-driven allergic diseases.

5-year share-count history (top 10 holders by peak, incl. exited) + price

Revenue Segments

Filing Risk Scores

Enanta Pharmaceuticals: Forensic Data Deficiency - Administrative Header Analysis

Full Earnings Call Transcript — Q2 • 2024-05-06

Operator: Good afternoon, and welcome to Enanta Pharmaceuticals' Fiscal Second Quarter Financial Results Conference Call. [Operator Instructions] Please be advised that this call is being recorded. I would now like to turn the call over to Jennifer Viera, Investor Relations. Please go ahead. 
Jennifer Viera: Thank you, operator, and thanks to everyone for joining us this afternoon. The news release with our fiscal second quarter financial results was issued this afternoon and is available on our website. Making remarks on today's call are Dr. Jay Luly, President and Chief Executive Officer; and Paul Mellett, our Chief Financial Officer. Dr. Scott Rottinghaus, our Chief Medical Officer; and Dr. Tara Kieffer, our Chief Product Strategy Officer, will be available during the Q&A portion of the call.
 Before we begin with our formal remarks, we want to remind you that we will be making forward-looking statements. These statements may include our plans and expectations with respect to our research and development pipeline and financial projections. All of these statements involve certain assumptions and risks beyond our control that could cause our actual developments and results to differ materially from the statements.
 A description of these risks is in our most recent Form 10-K and other periodic reports filed with the SEC. Enanta does not undertake any obligation to update any forward-looking statements made during this call.
 I'd now like to turn the call over to Dr. Jay Luly, President and CEO. Jay? 
Jay Luly: Thank you, Jennifer, and good afternoon, everyone. Throughout 2024, Enanta has remained squarely focused on advancing our virology and immunology pipeline to bring important oral therapeutics to market. Our commitment to developing treatments for areas of high unmet need is driven by our mission to transform patients' lives with curative therapies. And we are determined to achieve our milestones to drive near- and long-term shareholder value to fulfill this mission.
 Our focus is critical as we approach meaningful inflection points with the potential to develop the first antiviral treatment for RSV. With that, today, I'll begin with an overview of our programs, beginning with our respiratory syncytial virus or RSV programs and then discuss our immunology program for chronic spontaneous urticaria or CSU.
 As a reminder, RSV is a severe respiratory infection associated with significant morbidity and mortality that can cause serious disease in infants, children and other high-risk populations, including the elderly and individuals with congestive heart failure, chronic obstructive pulmonary disease, asthma or other high-risk conditions. Despite the availability of prophylactic options such as vaccines and monoclonal antibodies, there's a clear need for a safe and effective oral RSV antiviral treatment.
 Adoption of vaccines has been suboptimal, and breakthrough infections still occur. Additionally, pediatric monoclonal antibodies only provide passive immunity for a few months and not long-term protection against the infection. With this clear need, we have developed a broad clinical program that has the potential to enable multiple opportunities to treat RSV.
 RSV pipeline includes the most advanced clinical [ antiviral ] replication inhibitors: zelicapavir, formerly known as EDP-938, an N-protein inhibitor as well as EDP-323, an L-protein inhibitor. Zelicapavir is currently being studied in high-risk patient populations in two Phase II studies, RSVPEDs and RSVHR.
 RSVPEDs is the first in pediatric's Phase II randomized, double-blind, placebo-controlled study in hospitalized and nonhospitalized RSV patients aged 28 days to 36 months. The study, which will enroll approximately 90 patients, is being conducted in two parts.
 As this is a first in pediatric study, the objective of the first part is to evaluate the safety and pharmacokinetics of zelicapavir in multiple ascending doses to select the optimal dose for each age group. The second part of the study will evaluate the antiviral activity of zelicapavir at the selected dose. And virology and symptom scores will be assessed throughout the treatment duration.
 This study was designed as a small proof of concept in pediatric patients to show a trend toward improved virology metrics for zelicapavir compared to placebo and to give confidence to move forward efficiently into larger registrational studies. A key objective of this study is to show improvement in virology endpoints in patients on zelicapavir compared to placebo, sufficient to allow us to advance into Phase III.
 Currently, we have [ partially ] enrolled the last age cohort of 20 patients in part 2 of the study. As this cohort can only enroll patients 28 days to 6 months of age, the eligible population is narrower, and we will need to continue to recruit in the Southern Hemisphere. As we monitor the RSV season in the Southern Hemisphere, we anticipate reporting data from this study in the second half of 2024.
 RSVHR is a Phase II randomized, double-blind, placebo-controlled study of approximately 180 adults with RSV infection, who are at high risk of complications, including the elderly, those with congestive heart failure, chronic obstructive pulmonary disease or asthma. The primary endpoint for RSVHR is time to resolution of RSV lower respiratory tract disease symptoms as assessed by the respiratory infection intensity and impact questionnaire symptom scale.
 Secondary endpoints include additional clinical efficacy measures and antiviral activity compared to placebo, pharmacokinetics and safety of zelicapavir. The primary objective of this study is to show an improvement in time to symptom resolution.
 Given the study was designed to be a small Phase II proof-of-concept study, it is powered based on a 50% reduction in symptom resolution. However, as there are no data showing a statistically significant effect on symptoms in community-acquired RSV adult population with which to benchmark, this reduction likely represents a high bar.
 Therefore, directional efficacy data that is clinically meaningful would provide us with conviction to move directly into Phase III. Enrollment is progressing, and we will provide additional guidance on the RSVHR study as the Southern Hemisphere RSV season evolves.
 Also ongoing in our RSV portfolio is the Phase IIa challenge study of EDP-323, which is in development as a once-daily oral treatment for RSV. In this randomized, double-blind, placebo-controlled study, up to 114 healthy adult subjects will be infected with RSV and then randomized 1:1:1 to receive once-daily dosing of either 600 milligrams of EDP-323, 200 milligrams of EDP-323 with a loading dose of 600 milligrams on the first day or placebo for 5 days.
 Primary and secondary outcome measures include safety, changes in viral load measurements and changes in symptoms from baseline. The development of EDP-323 is supported by positive Phase I results in which the drug demonstrated favorable safety, tolerability and pharmacokinetics in healthy volunteers.
 We anticipate reporting data from this challenge study in the third quarter of 2024. We believe either zelicapavir or EDP-323 would be effective as a monotherapy. Because they do not have cross resistance, we could also potentially use them in combination to broaden the treatment window or expand the eligible patient population to harder-to-treat patients.
 Also in respiratory virology, data from SPRINT, our Phase II study of EDP-235, a 3CL protease inhibitor, was presented in April at the ESCMID Conference, formerly known as ECCMID. We are pleased to present this comprehensive data package in a scientific forum for the first time. As a reminder, we will conduct any future COVID-19 work in the context of the collaboration.
 I'll now turn to our work in immunology, where we are concentrating on indications with a high unmet medical need and a clear clinical development path, including well-defined populations and biomarkers available for early signs of efficacy. Our first immunology indication is CSU, a severely debilitating chronic inflammatory skin disease, which can continue for years before remission.
 Clinical manifestations include urticaria, commonly called hive, as well as angioedema, which is characterized by pronounced deep tissue swelling. The disease can be severely disabling, significantly impair quality of life and affect performance at work or school as patients with CSU can experience symptoms beyond the skin manifestations, including sleep disturbances, fatigue, irritability, anxiety and depression.
 CSU is estimated to affect 0.5% to 1% of the global population at any given time. The standard of care for CSU is antihistamines. But in approximately half of patients, symptoms are not alleviated, and a minority of patients are treated with one indicated biologic.
 Consequently, there is a substantial unmet need for a new efficacious drug that can be conveniently dosed as an oral agent. Mast cells are the primary driver for disease in CSU as well as being involved in multiple other allergic diseases.
 In our first immunology program, we are seeking to develop a best-in-disease oral KIT inhibitor treatment that reduces the number of mast cells available to drive pathology in patients suffering from CSU. We are also encouraged by the potential to study KIT inhibition in additional indications.
 Currently, our prototype KIT inhibitors in preclinical development demonstrate potent inhibition and are highly selective for KIT. We continue to optimize these leads around potency, selectivity and DMPK properties. And we are on track to select a development candidate in the fourth quarter of 2024 and plan to move into the clinic shortly thereafter.
 We are excited about our pipeline growth into immunology and are confident in the team's ability to translate the learnings from our previous success with small molecule drugs to enable our development of a best-in-disease therapeutic for CSU. We are also pursuing additional immunology targets and look forward to introducing a second program this year.
 Beyond our pipeline, I would also like to take a moment to welcome Matthew Kowalsky as our Chief Legal Officer, who joined last week. Matt is a strong addition to our team as he brings more than 20 years of experience in the life sciences industry, handling corporate governance, public company reporting, intellectual property, financing, business development and M&A activities. At Enanta, he will lead all legal and compliance activities for the company and provide strategic guidance and corporate governance oversight.
 With that, I'd like to conclude by highlighting our upcoming milestones. We anticipate reporting data from the Phase IIa challenge study of EDP-323 in the third quarter and reporting data from the Phase II pediatric study of zelicapavir in the second half of this year. Further, we plan to identify a clinical candidate for our CSU program in the fourth quarter. And finally, we also plan to announce second immunology program this year.
 Now I'll turn the call over to Paul to discuss our financials. Paul? 
Paul Mellett: Thank you, Jay. I would like to remind everyone that Enanta reports on a September 30 fiscal year schedule. Today, we are reporting results for our fiscal second quarter ended March 31, 2024.
 For the quarter, total revenue was $17.1 million and consists of royalty revenue earned on AbbVie's global MAVYRET net product sales. This compares to total revenue of $17.8 million for the same period in 2023.
 As a reminder, our royalties are calculated on a calendar year basis. Therefore, royalties for our fiscal first quarter ending December 31 were calculated at 12%, the highest royalty rate for the year. And royalties for our fiscal quarter ending March 31 are calculated at 10%, our lowest royalty tier.
 Of note, 54.5% of Enanta's ongoing royalties from AbbVie's net sales of MAVYRET that are included in our revenue are being paid to OMERS, the royalty buyer, in our April 2023 royalty sale transaction. For financial reporting purposes, the sale transaction was treated as debt with the upfront purchase payment to us of $200 million recorded as a liability.
 As such, we continue to record 100% of the royalties earned as revenue and will then amortize the debt liability as 54.5% of the cash royalty payments are paid to OMERS through June 30, 2032, subject to a cap of 1.42x the purchase payment, after which point, 100% of the cash royalty payments will be retained by Enanta. Interest expense from the debt will be recorded in Enanta's consolidated statement of operations based on an imputed interest rate. Interest expense was $2.6 million for the 3 months ended March 31, 2024.
 Moving on to other expenses. For the 3 months ended March 31, 2024, research and development expenses totaled $35.6 million compared to $43.5 million for the same period in 2023. The decrease was primarily due to a decrease in costs associated with our COVID-19 program as we previously announced that plans to pursue any future COVID-19 efforts would be in the context of a collaboration. This was partially offset by increased costs associated with our RSV program and our recently announced immunology programs.
 General and administrative expense for the quarter was $14.2 million compared to $13.8 million for the same period in 2023. This increase was primarily due to an increase in legal expenses related to our patent infringement lawsuit against Pfizer.
 Enanta recorded an income tax benefit of $0.4 million for the 3 months ended March 31, 2024, for interest earned on a pending $28 million federal income tax refund compared to an income tax expense of less than $0.1 million for the 3 months ended March 31, 2023. Net loss for the 3 months ended March 31, 2024, was $31.2 million or a loss of $1.47 per diluted common share compared to a net loss of $37.7 million or a loss of $1.79 per diluted common share for the corresponding period in 2023.
 At this fiscal year midpoint, we are updating our expense guidance. We now expect our research and development expense to be between $125 million and $145 million, and our general and administrative expense to be between $50 million and $60 million.
 The research and development expense increase reflects the impact of our new immunology program as well as additional efforts to accelerate our RSV clinical studies. The general and administrative expense increase is due to additional stock compensation expense and costs associated with pursuing our patent infringement lawsuit.
 Enanta ended the quarter with approximately $300 million in cash and marketable securities. We expect that our current cash, cash equivalents and short-term marketable securities as well as our retained portion of ongoing royalties will continue to be sufficient to meet the anticipated cash requirements of our existing business and development programs through the third quarter of fiscal 2027. Further financial details are included in our press release and will be available in our report on Form 10-Q when filed.
 I'd now like to turn the call back to the operator and open up the lines for questions. Operator? 
Operator: [Operator Instructions] And our first question comes from Akash Tewari from Jefferies. 
Unknown Analyst: This is Kathy on for Akash. So I had a question for RSVPEDs. Since RSVPEDs isn't explicitly powered to hit on viral loads or symptoms, what will you be looking at in terms of the data to inform your design for Phase III? And as such, how should we think about gauging efficacy or safety? And then how much of a read across do you believe the data will have for RSVHR? And then are you expecting a symptom benefit of like 1 or 2 days? 
Jay Luly: Thanks for the question. This is Jay. I think I'll hand it over to Tara Kieffer to talk about how we were going to be viewing the data set coming out of PEDs. Tara? 
Tara Kieffer: Sure. Yes. So the RSVPEDs study is our proof-of-concept Phase II study in pediatrics. So we have to think about it a little bit differently than our adult study in Phase II because this is the first time that we're dosing children in this young age range of 28 days to 3 years. So we have to first confirm the safety profile and the dose.
 And so the study has been done two parts. Part one, the primary endpoint is safety and PK and done in a dose-ascending fashion. And we select the optimal dose from that part, which has been studied in part 2. And in that part, the primary objective is to look at the virology endpoints.
 So we're primarily again looking for improvement in virology endpoints between the patients on 938 or zelicapavir and placebo with directional data that would give us the comments to move into a Phase III study. So we'll look at a number of different virology endpoints.
 We'll also look at the clinical endpoints as well, but primarily, we'll be looking at virology. It's hard to give a specific threshold or a bar in terms of what we're looking at because there's not a lot of data out there in RSV for naturally acquired RSV in children.
 So there's one study that we can point to from a company called [ Arc Bio ] that did a Phase III study in pediatrics in China. And they did show a 0.6 log drop at day 4, a statistically significant effect in virology. And they also, in that same study, demonstrated an improvement in symptoms.
 So we're not able to [ really give ] any kind of a bar that we're looking for, but we're really interested in the totality of the data and showing those trends and directional data that would give us the confidence to move into a larger, more well-powered study to able to tease out these effects. 
Operator: [Operator Instructions] And our next question comes from Eric Joseph from JPMorgan. 
Eric Joseph: Great. Just a couple of questions related to the immunology program for this KIT development candidate. Can you talk a little bit about your strategic plans with respect to clinical development there? I guess to the extent you might be seeking a strategic partner at some point along the way, are there -- is there a certain sort of hurdles, kind of milestones you want to see cleared first?
 And then secondly, just noting that you're looking to expand into or expand with a second immunology program. Can you give us a bit of a preview there in terms of either target you might be pursuing? Are you perhaps doubling down on KIT? 
Jay Luly: Thanks, Eric. This is Jay. So we're working up a few different approaches in parallel to figure out which we might prioritize going forward. So it's a little early to be discussing it.
 I think you asked were we doubling down on KIT. I mean we have one major KIT program now. I think we're looking to broaden beyond that. And so we'll provide more detail as the year progresses and after we've generated more data in-house, made more molecules in-house, filed intellectual property and so forth. So stay tuned on that front.
 With regards to -- I wasn't quite sure on your -- the first part of your question. You were talking about strategic partnering. I mean our plan just in a nutshell, initially at least, is to again, identify the candidate in the fourth quarter. We're going to be aiming to get it into the clinic, hopefully, rapidly thereafter.
 And then Phase I, I think, should be fairly straightforward and healthy. The nice thing is with this mechanism, you can get sort of surrogate readouts of target engagement by looking at tryptase changes. So that will help a lot, having the biomarker available to us.
 And then the clinical development in CSU, I think, is actually pretty straightforward. So we would be thinking about progressing to a fairly straightforward proof-of-concept study. It's a defined, accessible and large patient populations. So we hopefully won't have the seasonal trends that we experienced in RSV and are looking very much forward to progressing that first program in immunology and then again, bringing on additional targets and mechanisms as time goes on. 
Tara Kieffer: Can I just add one thing to that, Jay, is the biomarker that Jay mentioned we can monitor in Phase I in healthy volunteers is serum tryptase. There's a lot of data out there generated from some of the monoclonal antibodies against KIT from Celldex that have nicely been able to show a tight correlation with impacts on that biomarker and ultimate clinical outcomes. So I think it's something that really can derisk the program early on in those Phase I studies. 
Operator: [Operator Instructions] And our next question comes from Ed Arce from H.C. Wainwright. 
Wing Yip: This is Thomas Yip asking a couple of questions for Ed. So first, can you outline what's your estimate of patient population breakdown between the Northern and Southern Hemisphere to date, both for the RSVPEDs study and also for the HR study as well? 
Jay Luly: Are you making reference to numbers of sites? You say patient population, but are you talking about markets? Are you talking about clinical trial conduct? 
Wing Yip: More on the clinical trial conduct so perhaps the number of sites. So both the number of sites or the number of patients enrolled, just to have a ballpark [ percentage ]. 
Jay Luly: Yes. I don't have the exact figures in front of me. We have -- I mean maybe, Scott, maybe I'll just let you amplify on that. 
Scott Rottinghaus: Yes. Sure. Thanks, Jay. So we've enrolled patients in both Northern and Southern Hemispheres in both the pediatric and the high-risk studies, including in the current season ongoing in the South. So I don't have the exact numbers in front of me either, but we are continuing to enroll actively in both of those studies. And as Jay mentioned on the call, in the pediatric study in particular, we're down to the last cohort and enrolling in the South. 
Jay Luly: Yes. I -- but I think directionally, maybe your -- the Northern Hemisphere, beyond question, is more highly represented in terms of clinical trial sites than the Southern Hemisphere. I mean we're in many different European countries, many different North American countries. We're in Asia.
 In the Southern Hemisphere, we're in South Africa, we're in Brazil, we're in Argentina, New Zealand, Australia. Not as large a footprint in the Southern Hemisphere, but nonetheless, we're hoping to make good progress on enrollment in that and wrap this up as soon as possible. 
Wing Yip: Understood. And then as a follow-up on that, can you remind us how much overlap are there between the Southern Hemisphere RSV season or flu season? And also, do you expect -- to that point for the HR study, do you expect the slate to complete enrolling kind of in line with the conclusion of the Southern Hemisphere RSV season? 
Jay Luly: Did you -- was the first question about overlap with the flu season? 
Wing Yip: Yes. How much overlap are there between the RSV season and the flu season? 
Jay Luly: I mean, generally, they're somewhat correlated. But even in any given year, they can deviate a little bit one way or the other. Flu could come on a little earlier or a little later, come on twice. RSV has been -- and flu, but especially RSV have been substantially impacted by the pandemic years in terms of just only more recently starting to settle down into what we would call more normal seasonality. So I think, again, we follow -- we track the RSV season much more closely than flu.
 As it relates to HR, my guess is we'll need to come back to the Northern Hemisphere, given that we, again, have just much stronger footprint there. We made excellent strides in the Northern Hemisphere this year. That's why, especially in the United States, it was a very nice season for us. So we may need some of that as well.
 We'll -- again, we'll be tracking this and reporting progress later this summer when we're well into the Southern Hemisphere season. And we'll be able to forecast a little bit better based on more current data. But that's my expectation. 
Operator: [Operator Instructions] And the next question comes from Roy Buchanan from Citizens JMP. 
Roy Buchanan: Just a couple on RSV. Jay, for the RSVHR, I think I heard you say that it's powered for a 50% reduction in symptoms. It's probably a high bar. Just wondering where that, I guess, conclusion about it being a high bar comes from. I think that challenge trial, you had a 75% reduction in symptoms. And are you just interpolating between that and RSVPEDs? Or is there something you're seeing in the trial? 
Jay Luly: Yes. So to be clear, we're talking about time to resolution of symptoms. So it's different than in the challenge. We're looking at the number of days improvement in time to resolution of symptoms versus placebo. I mean I can give a little color on that.
 I think, for example, with flu, in a placebo study and Tara can correct me if I'm wrong, there's about a 4-day time period for a time to resolution, and Tamiflu will shorten that by a day. So it's a 3-day time -- so it's a 1-day shortening out of 4 days. That's a 25% improvement in time to resolution.
 And so the way this was powered with HR and in order to keep it a relatively small study of only just under 200 patients, it was powered on a 50% effect. Have we powered it on a 25% effect that the study would be even much larger.
 So it's that fine balance of running a Phase II that is enabling of a pivotal trial, keeping it at a manageable size. And we felt with a couple of hundred patients, even though it's a high bar to reach a [ stat ] on the way it was powered, we should be able to make good decisions based on a clinically meaningful improvements. And again, shortening time to resolution of symptoms by one or more days would be clinically meaningful. 
Roy Buchanan: Okay. Makes sense. And then for the 323 challenge, what are you hoping to see there? We've said many times that zelicapavir data is probably best-in-class. Are you expecting to see something similar? Do you need to see something similar? Just help us think about that. 
Jay Luly: Yes. Zelicapavir does set a high bar. The mechanism is an N-protein inhibitor. It is about the best challenge study data any company's ever put on the board. So it does represent a high bar.
 That said, 323 is another mechanism. It's a polymerase inhibitor. It's a [indiscernible] polymerase inhibitor, so it's super potent. Can we replicate the same best-in-class data that we saw with zelicapavir? We'll see. Hopefully, yes. It's hard to do much better. I think we want to be in the same range to declare it as a strong player in the field.
 But based on every bit of data that we have frequently in our Phase I data, which show good safety, tolerability, wonderful exposures after QD dosing and again, very, very strong virology, we've set it up about as best as we can. We're running it at the same clinical site as we ran the zelicapavir trial. So we'll see. So we should have data for that in Q3, next quarter. 
Operator: [Operator Instructions] And our next question comes from Roanna Ruiz from Leerink Partners. 
Unknown Analyst: This is [ Mick ] on for Roanna. Maybe first on RSV. Could you give us a sense of how close you are to completing enrollment of the younger age cohort of RSVPEDs? Maybe how long do you think it could take to analyze and ultimately share the data afterwards? 
Jay Luly: Yes. Again, so there are two parts to the study. Part one is completed in all age cohorts. Part two of the study is done in the older age cohorts, and we're down to the final cohort of 20 patients. It's the youngest children from age 28 days to 6 months. And we've been actively recruiting that cohort. So we're in the home stretch.
 And we just -- unfortunately, we can -- our pool of patients is now only 1/6 of what it was based on age groups. So it's a narrower pool, and any older children, we really have to -- we can't enroll in the study any more. So we're just really zeroed in, focused on getting the remaining young children to fill out this cohort. 
Unknown Analyst: Got it. And then maybe on CSU, curious, what are you hoping to see in a future Phase I for your oral KIT inhibitor in terms of safety? Maybe how should we think about frequency of administration for this asset? Is it a once daily, twice daily? How should we think of that? 
Jay Luly: Well, we're still finalizing the candidate again. We were targeting to have the finalist in Q4. But suffice it to say, we're very much zeroed in on QD dosing. We've made molecules that are very potent. They're very selective. We're optimizing DMPK profiles, tissue distribution, a number of other sorts of parameters like that to make it the kind of candidate that we typically bring forward.
 So we've already shown data on a strong prototype. And we continue to -- the chemists are very busy, well, not just chemists, but the chemists and all the biology people who are doing the characterization. And our DMPK and safety team are working very, very diligently on this. So we would be aiming for a QD candidate that would be -- have the best safety profile we can provide as well as good potency in selectivity. 
Operator: [Operator Instructions] And our next question comes from Brian Skorney from Baird. 
Luke Herrmann: This is Luke on for Brian. For EDP-323, can you remind us of your current thoughts on potentially entering a Phase IIb in otherwise healthy adults as opposed to starting with the high-risk and pediatric populations like you've done with zelicapavir? And would you wait for RSVPEDs or RSVHR data to make this decision? 
Jay Luly: Yes, that's a good question. I mean the short answer is we won't do another RSV study in otherwise healthy adults. They just -- we found out from our RSVPED trial that they're -- otherwise healthy folks just resolve the -- self-resolve the infection so quickly on their own. So they're really not in need of a therapy.
 We would only focus on high-risk patient populations. And we're hoping to have an abundance of data here in the second half. We'll have 323 data. We'll have PEDs data. We'll be able to look at the totality of the information and figure out how best to position 323.
 So for us, it's been about bringing another strong mechanism forward. We've been working on this from the beginning. I guess we've been working on it for a few years now to bring forward another differentiated asset in RSV. And that could give us the potential for doing combination therapy down the road and particularly hard-to-treat patient populations.
 Potentially it could help widen the treatment window where we to go after a patient with two drugs rather than one. So it's just part of our strategy overall to try to build a leadership position in RSV as a therapeutics company.
 And the more sort of cards we have to play, I think we can come up with ways to leverage another asset over time. So the key is getting it up to a strong threshold on the challenge study data first. 
Operator: [Operator Instructions] And our next question comes from Liisa Bayko from [ EVR ]. 
Unknown Analyst: This is Tina on for Liisa. I have a question on the 323 program. What doses of 323 are you testing in Phase IIa human challenge study? 
Jay Luly: Yes. So we're looking at a couple of different dose regimens. So the first is 600 milligrams straight across for 5 days. The other is 600 milligram loading dose on day 1, followed by 200 milligrams on each subsequent day. It's kind of like in antibiotics, they do that sometimes. They give you a loading dose on day 1 and then a lower maintenance dose for a few days thereafter.
 So we just look both of them in. And I think in theory, either at least based on calculations and modeling, either has a good chance of demonstrating the activity we want. One obviously is a lower dose and has different cost of goods ramifications, et cetera, et cetera.
 So we're just -- the challenge study is just such a wonderful way to tease all those kinds of questions out because you don't have to wait for the season. You can just [ infect ] human volunteers, line cohorts up every few weeks and dose them. So does that answer your question? 
Unknown Analyst: Yes. That's helpful. I have a second question, the patent against -- the case against Pfizer because [indiscernible] said that Paxlovid doesn't infringe the patent because Paxlovid has [indiscernible] group, which is not described in your patent. So if you can comment on that. 
Jay Luly: Yes. I really can't get into the discussion on our ongoing patent litigation. The only -- but the only thing I can say is that assuming that it were to go to trial, we would expect a trial around the end of the year. 
Operator: [Operator Instructions] And our next question comes from Jay Olson from Oppenheimer. 
Jay Olson: On the immunology program, what are the most important differentiators you're looking for with your oral KIT inhibitor candidate versus other oral KIT inhibitors in development? And how are you thinking about positioning oral KIT inhibitors versus other oral therapies for CSU such as BTK inhibitors? 
Jay Luly: Thanks for the question, Jay. I'll let Tara speak to that. 
Tara Kieffer: Sure. So I think some of the data that's been generated from the monoclonal antibodies against KIT, that would be from Celldex and then an earlier program with Jasper have indicated that this target -- inhibiting this target has some of the best-in-disease efficacy at least from the Phase II trials that have been run. So that gives us confidence in the target.
 And what we're really hoping for our program is to match or even exceed potentially that efficacy with a good safety profile just with an oral route of administration. So that's the goal of our program.
 As you mentioned, there's other companies working on this as well. They're all early. They're all preclinical at the moment. There's really only preclinical data at the moment. So it's hard to sort of say what would be differentiated.
 But I can tell you what our program is looking to achieve, and that would be something that is able to be dosed QD, orally, something that is very potent against KIT but selective. And so leading to a good safety profile and just balancing that potency and selectivity so that the efficacy and safety profile could potentially be something that you would have as best-in-class.
 And then I would just say that the oral inhibitors be more tunable. I think this is something that remains to be proven in the clinic. But whether they're able to be dosed and tuned more finally than a monoclonal antibody, you can certainly have a little bit more flexibility over that. So I think it remains to be determined but one potential strategy as well. 
Jay Olson: Okay. Great. And then can you just talk about how you're thinking about additional indications in your development plan beyond CSU? 
Tara Kieffer: Sure. You mean for the KIT inhibitor? 
Jay Olson: Yes. 
Tara Kieffer: Yes. So the reason that we're interested in KITs is it obviously is a key driver for mast cells. And we know that mast cells have been implicated in a number of different indications. So certainly, chronic inducible urticaria or [ CINDU ] is something that's also been studied with this target, and there's some good data from the monoclonal antibodies here. EOE or eosinophilic esophagitis is also another indication we'd be interested in, PN as well and even potentially asthma is something that one could think about with these types of inhibitors. 
Operator: And I am showing no further questions. I would now like to turn the call back over to Jennifer Viera for closing remarks. 
Jennifer Viera: Thank you, operator, and thanks to everyone for joining us today. If you have additional questions, please feel free to contact us by e-mail or call the office. Have a great night. 
Operator: This concludes today's conference call. Thank you for participating. You may now disconnect.