Good afternoon. My name is Sarah and I will be your conference operator today. At this time, I would like to welcome everyone to the Enanta Pharmaceuticals First Quarter Financial Results Call. All lines have been placed on mute to prevent any background noise. After the speakers' remarks, there will be a question-and-answer session. [Operator Instructions]. It is my now pleasure to introduce your speaker, Ms. Carol Miceli, Director Investor Relations. Ms. Miceli, you may begin your conference.

Thank you, Sarah and welcome to Enanta Pharmaceuticals first quarter conference call. The news release with our financial results was issued this afternoon and is available on our website. On the call today is Dr. Jay 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, including plans and expectations with respect to our product candidates and financial projections, all of which involve certain assumptions, risks and uncertainties that are beyond our control and could cause our actual developments and results to differ materially from these statements. A description of these risks and uncertainties is in our most recent Form 10-K and other periodic reports filed with the SEC. In addition, 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.

Thank you, Carol. Good afternoon everyone and thank you for joining us today. I'll begin by providing updates on our key development programs and then Paul Mellett will discuss our financial results for the quarter. For some of our listeners on the call today who are new to our company, our strategy over the past several years has been to use our drug discovery expertise to develop best-in-class compounds in virology and [Indiscernible]. Our first two successes were in HCV, with our protease inhibitors glecaprevir and paritaprevir, developed and commercialized through a collaboration with AbbVie. We are continuing to build on that success by using the royalties provided by that collaboration to fund our wholly-owned programs in NASH, PBC, RSV and HBV. Among these wholly-owned assets, the most advanced is EDP-305, our FXR agonist candidate for NASH and PBC. We continue to believe that FXR agonist have the potential to be cornerstone agents in combination therapy for NASH. EDP-305 is a highly selective and potent FXR agonist that successfully completed a Phase 1 a/b clinical study last year and was granted fast-track designations from the FDA for the treatment of NASH patients with liver fibrosis and for the treatment of PBC patients. Recently, we initiated a Phase 2 clinical study of EDP-305 in patients with PBC. This Phase 2 clinical study named INTREPID, is a 12-week randomized, double-blind, placebo-controlled study evaluating the safety, tolerability, pharmacokinetics and efficacy of EDP-305 in subjects with PBC, with or without an inadequate response to ursodeoxycholic acid. The efficacy of EDP-305 will be assessed by evaluating reductions in levels of alkaline phosphatase, or ALP versus placebo. Today, we are announcing that we've also recently initiated recruitment of a Phase 2 dose-ranging clinical study of EDP-305 in NASH patients. This Phase 2 clinical study named ARGON-1,…

Thank you, Jay. I'd like to remind everyone that Enanta reports on a fiscal year schedule. Our fiscal year ended September 30th and today, we are reporting results for our first fiscal quarter ended December 31, 2017. Enanta ended the quarter with approximately $298 million in cash and marketable securities as compared to $294 million at our September 30th, 2017 fiscal year end. We expect that these cash resources and our future royalty revenue stream from our AbbVie agreement will be sufficient to meet our anticipated cash requirements for the foreseeable future. For the three months ended December 31, 2017, revenue was $38.1 million compared to revenue of $10.4 million for the same period in 2016. The increase in revenue in the current quarter was primarily due to a $15 million milestone payment received for the reimbursement approval of MAVIRET in Japan as well as an increase in royalties earned on AbbVie's global net sales of hepatitis C virus regiments due to the launch of MAVIRET in major markets in the second half of 2017. Royalty revenue in the current quarter was $23.1 million based on AbbVie's global HCV sales of MAVIRET and VIEKIRA totaling $510 million. Moving on to our expenses. For the three months ended December 31, 2017, research and development expenses were $18 million compared to $12.5 million for the same period in 2016. The increase in research and development expense was primarily due to increased preclinical and clinical costs associated with the progression of our wholly-owned R&D programs in NASH, PBC, RSV, and HBV. General and administrative expenses for the quarter was $5.8 million versus $4.9 million for the comparable quarter in 2016. The increase in these expenses was primarily due to an increase in headcount. Enanta recorded income tax expense of $3.6 million for the three months ended December 31, 2017 compared to an income tax benefit of $1.5 million for the same period in 2016. Income tax expense for the three months ended December 31, 2017 includes a $3.8 million non-cash revaluation charge that decreased our deferred tax assets to reflect the reduced federal corporate income tax rate as a result of the enactment of the U.S. Tax Cuts and Jobs Act in December 2017. Net income for the three months ended December 31, 2017 was $11.7 million or $0.59 per diluted common share compared to a net loss of $5 million or $0.26 per diluted common share for the corresponding period in 2016. Note that net income for the three months ended December 31, 2017 reflects the $3.8 million or $0.19 per diluted common share noncash revaluation charge I previously discussed. Further financial details are available in our press release and will be available in our Form 10-Q for the quarter when filed. I'd now like to turn the call back to the operator and open the lines up for Q&A. Operator?

Thank you. [Operator Instructions] Your first question comes from Brian Abrahams with RBC Capital Markets.

Hi guys. Thanks very much for taking my questions and congratulations on all the progress. My first question is on 305. Question about your dose selection for the Phase 2s. And just curious if you could talk about some of the factors that guided your dose selection there. Obviously, there's some inherent variability based on variability patient to patient and diurnal variation in the C4 and FGF19 biomarkers. So, I'm wondering sort of how you put all that data together from the Phase 1 study combined with some of the tolerability data to arrive at the -- and obviously, the new formulation to arrive at the one and the 2.5 mg dose?

Sure. So, thanks for the question, Brian. So, this is Jay. We went through the data we presented the Phase 1 data. We top lined it last fall and we presented it at NASDAQ early this year. And we showed how we had looked at a number of different factors, safety, biomarkers, et cetera, et cetera, PK exposure. Our goal is to give very good once-daily dosing coverage. We also wanted a good safety profile. As you know, at the high 20 milligram dose sort of we got into the non-linear range on the PK and the exposures popped up a bit and that's the dose where we saw the predominant amount of pruritus, at doses below 10 milligrams, we didn't see that. Also in that dose range, we saw no effects on LDL and so from our perspective of safety and tolerability and looking at pruritus and lipids and also looking at sort of PD markers of efficacy "of FGF19 and C4", we saw good target engagement that doses well below that top dose those. So, coming down from there, picking a dose below 10, we started thinking about our five milligram dose of a suspension, which as we pointed out -- we've pointed out previously, but also just in the remarks, that our new tablet suspension gives us basically twofold extra exposure versus the suspension. So, we could essentially get 5 milligrams of the suspension covered by our 2.5 milligram tablet. So, at one and 2.5 milligram tablet equivalents, again, we see for the target engagement, we don't effects on lipids, we don't see pruritus and we just felt two solid doses to explore in these two Phase 2 studies.

Got it. Now that makes a lot of sense. And then can you talk a little bit more about the endpoint that you're looking at in NASH. Maybe the predictive value of ALT and some of -- what are kind of the most important non-invasive metrics and imaging measures that you're going to be looking at in the 12-week NASH study?

So, ALT, I think if you go back and you look at the FLINT study, I mean, ALT was one of the key parameters looked at. So, I think, especially for a 12-week study, again, this is a shorter duration study. We want to take a look at ALT reductions. As you know, we'll be looking at patients who already have elevated ALTs. Their [Indiscernible] they have either been phenotypically characterized as having NASH or have logically been characterized as having NASH. In fact, you can look on clinicaltrials.gov for a lot more information on this because we have just recently posted this week the trial design. But ALT is a great surrogate to look at for a NASH activity. And of course, we'll -- you'll see from our inclusion criteria that we're looking at facts, steatosis and -- so you can imagine we're using imaging as secondary endpoints, et cetera, also biomarkers of fibrosis. So, I think it'll be a compact 12-week study that should give us a lot of information. I think we've picked two interesting doses to explore. And we're going to now have that up and running alongside the PBC study. And again, both those studies are targeted to readout in 2019.

Got it. One last question if I may, more of a housekeeping question. Congrats on the strong uptick of the HCV -- of the new HCV cocktail. Just wondering if you might be able to break out for us, the hep C royalties that are deriving from MAVIRET versus VIEKIRA versus some of the other cocktails? And I'll hop back in the queue. Thanks.

Yes, I think we can't give that breakdown right now. So, just to be clear, we get royalties on VIEKIRA and VIEKIRAX and TECHNIVIE all the paritaprevir any regimens. All of those sales go into one bucket and MAVIRET sales into another bucket and we get royalty streams on each of those buckets. But certainly from the VIEKIRA some of that are 3-DAA regimens, the majority of the VIEKIRA's AA regimens, but there's also some 2-DAA in there where we get a different blend. And then in the separate bucket, we've got MAVIRET where we get a double-digit royalty on 50% of those sales. So, this is all gotten aggregated together. And let's just say we won't get any more granular than AbbVie does in terms of reporting out those various sales. What I can say is it's a pretty reasonable expectation. Going forward, MAVIRET is going to be the key driver in the HCV growth and I think it's at a very exciting time. You can see just after MAVIRET was basically launched in the EU and only part of the EU starting in July and then the U.S. in August. So, to see that kind of calendar Q4 performance in such a short period of time, I think is just -- is really impressive. And so while others are reporting declines in their HCV revenues, I think Enanta has the potential to be, sort of, the growth story for hepatitis C, at least in the near-term.

Great. Thanks very much Jay.

Welcome.

Your next question comes from Jessica Fye with J.P. Morgan.

Great. Thank you. Just a few from me and maybe just a follow-up on the prior question. Do you have a sense of how quickly the international markets will convert over to MAVIRET? It seems like that's happening very rapidly in the U.S. I'm curious if there are any reasons to think the international markets will proceed differently? I also wanted to just talk about the cadence of pipeline readouts over the next 12 to 24 months. So, specifically, the RSV sees one data. Is that mid-year we should be thinking about that or more like 3Q? And with the RSV challenge data, if that study starts in 4Q, when could we expect to hear an update on those results? And lastly, what about the timing within 2019 for those Phase 2 readouts for 305? And just the last one on the tax rate, is it safe to assume a 21% tax rate going forward or is there -- are there any other factors we should think about that might affect that? Thank you.

Okay. So that was six questions, I think.

Yes, [Indiscernible].

Let's start -- let's go all the way back to the HCV 1. So, on the ramp there, I think VIEKIRA is sold in dozens and dozens of countries. It's well over 50 countries globally and I think there's just a part of getting MAVIRET in every nook and cranny around the world. So, VIEKIRA sales will be -- obviously, continuing until -- well, probably continuing even as MAVIRET comes into a particular territory. But given the profile and the simplicity and the overall efficacy of MAVIRET it's reasonable to assume that, that transfer what happened very quickly in all the various territories just as it has happened in the United States. So, they are continuing to launch globally very aggressively. I pointed out some of the key territories in Europe that they commented on. Well, the other thing I'm excited to see, the MAVIRET was just approved in Japan in September, but it didn't get pricing approval until November. So, any Japan contribution for calendar Q4 was not -- certainly not a full quarter baked in there. So, we'll see in calendar Q1 just how Japan could potentially add to all of the sub. Anyway, I think MAVIRET switchover will be pretty seamless but in the meantime, VIEKIRA will continue to sell. So, thinking about RSV, I mean, we just started the Phase 1 a few weeks ago and these things usually take a few quarters to conduct and then we'll pull down the topline data and analyze it. So, I would say maybe sometime in the Q3 timeframe. But we'll give an update on that as we progress the study. Then Q4, we would plan to start the challenge study. Having our dose planning well in line to get that done. So, data from that, obviously, will also…

Sure. This is Paul, Jessica. Our effective rate for the quarter was 24%. But I'd say at this point, we're not going to provide guidance for the rate for the full year, since it's ultimately going to be a function of revenues and how that impacts the bottom-line and also the level of R&D credits that generated by our spending this year. So, for those reasons we'll perhaps consider our guidance down the road, but not at this time.

Okay. Thank you.

[Operator Instructions] Your next question comes from Liisa Bayko with JMP Securities.

Hi Jay, congratulations on all the progress. I was wondering if you could dig a little bit more into your NASH study in particular. Just because we haven't -- I guess, from Intercept, for example, we haven't seen a tremendous amount of early data for that program, of course, we have for Novartis and stuff. So, I guess benchmark for us and tell us, what kind of magnitude of change are you looking for with respect to ALT and some of the other markers, you're looking at fibrosis and steatosis that what -- first of all, what they are specifically? And then also what kind of magnitude of change are you looking to see to feel good about this compound?

Sure. So, to the extent we have benchmarks or there may be benchmarks in the future from Novartis and Gilead. We'll be preparing ourselves for them for sure. The really -- the only benchmark that we have right now is -- in this type of study is ALT. And I think, if you go back to FLINT, it was sort of in the 20% to 30% reduction range over that time course. So, I think we would be looking to do at least that. And then with regards to biomarker and imaging data, I think there's not a lot of strong data for comparisons there yet. Certainly, not out of Intercept. So, we'll be waiting for Gilead and Novartis to put that data out. And likely, we don't know exactly everything that they're measuring, but likely, there will be an intersection some of our markers and some of theirs as well, with regards to imaging and other things that we'll be able to line up some comparisons. It is a short-term duration -- short-duration study I would also point out, again, this is sort of a 12 week. So, this isn't a 50 or 72-week or a yearlong study, but it's mean to drive key relevant markers, help us gain confidence on efficacy and dose selection, and then to build the stage for moving on to later stage studies.

Yes, that's why I was asking the question, I just was trying to understand what you were trying to see with the FXR approach on some of these things in such a short period of time, vis-à-vis some of the other mechanisms that may be directly focusing on reducing fat that we might expect a big change on that in 12 weeks?

Well, FXR already does have a lot of things. It's certainly -- it certainly has -- if you look at fibrosis and inflammation and gluconeogenesis and fat, you can -- there's certainly a strong mechanistic rationale for why FXR is tied into all of them, which is going to be the most profound driver in the end is something that we're going to have to figure out. So, some drugs that focus more purely on steatosis as one dimension. We'll have to see how an FXR will stack up against them, against that dimension. But again, we're looking at FXR as being sort of a central regulator of many of the different mechanisms. And so it's the aggregate of the approaches that I think make FXR really compelling.

Jay, where do you kind of -- what's your thinking with respect to FXR being the backbone of NASH therapy that was originally thought to be the case and now there's a lot of mechanisms of them? I'm curious how you see kind of the--

All right. There could well be more than one backbone before it's all over. I mean, again, I'm just looking at it from a perspective of how many mechanisms have true validation in a NASH sighting and the list is relatively few. There can be multiple other backbones, so I'm not excluding others. But we think that FXR is going to be a key one and we're happy to think about adding other mechanisms onto that. So, I don't mean to imply that FXR will be the only such one. As you know, there were few HCV analogy, there were some backbones that were nuke-related, and then others that weren't. And early on, people, I think incorrectly assumed that one backbone would be the only backbone you would ever find. I think there's -- especially in something like NASH that has so many factors going on, I think there's different ways to think about the problem and different ways to approach it.

Okay, great. Thank you.

There are no further questions at this time. Ms. Miceli, do you have any further remarks?

Yes sure. Thank you, everybody for joining us today. If you have any additional questions, feel free to give us a call in the office. Thank you.

This does conclude today's conference call. You may now disconnect.