Good day, ladies and gentlemen. And welcome to the BioCryst First Quarter 2018 Earnings Conference Call. At this time, all participants are in a listen only mode. Later, we will conduct the question-and-answer session and instructions will be given at that time. [Operator Instructions] As a reminder, this call is being recorded. I would now like to turn the conference over to Tom Staab, Chief Financial Officer. Please begin.

Thank you, Latoya. Good morning, and welcome to BioCryst's first quarter 2018 corporate update and financial results conference call. Today's press release and accompanying slides are available on our website. Participating on the call with me today are Jon Stonehouse, Chief Executive Officer and Dr. Bill Sheridan, Chief Medical Officer. Following our formal remarks, we will answer your questions. Before we begin, I want to direct your attention to Slide 2, which discusses our use of forward-looking statements and potential risk factors regarding an investment in BioCryst. As detailed on the slide, today's conference call will contain forward-looking statements, including those statements regarding future results, unaudited and forward-looking financial information, as well as the company's standalone future performance and/or achievements. These statements are subject to known and unknown risks and uncertainties, which may cause our actual results, performance, or achievements to be materially different from any future results or performance expressed or implied in this presentation. You should not place undue reliance on these forward-looking statements. For additional information including a detailed discussion of our risk factors, please refer to the company's documents filed with the Securities and Exchange Commission, which can be accessed on our website. I would now like to turn the call over to Jon.

Thank you, Tom, good morning, and thanks for joining us today. We got off to a strong start in 2018, implementing our plan, advancing our programs, and announcing our strategy for optimizing long-term value. The most advanced of our programs has BCX7353, a late-stage program testing the first once a day oral medicine for the prevention of hereditary angioedema attack or HAE. The pivotal trial for that program, APeX-2 is up and running and enrolling rapidly which is good for the clinical trial and is also a good indicator for the demand of this one capsule once a day treatment. Most of the planned APeX-2 sites in the U.S. are now up in screening patient. In addition, we recently held our investigator meeting in Europe and expect to be screening patients at European sites in the coming weeks. So we remain on track to report efficacy and safety results from the first 24 weeks of this trail in the first half of next year. Our strategy for the pivotal prophylactic program is to prioritize enrollment of APeX-2 first. And utilize U.S. sites for this trial only until part one the first 24 weeks is completed. Our next priority is the open label safety trial for 7353 called APeX-S. Enrollment for APeX-S is focused outside of the U.S. initially in Europe and is also now running and enrolling. Like our previous EU trial, this trial has a slower ramp up due to longer sites start-up time. Safety data from this trial is an important component of the NDA filing. Our target for filing in the second half of 2019 remains on track. In addition to HAE prophylactic, we are also studying 7353 for treatment of acute attack. Zenith-1, our Phase 2 clinical trials for acute treatment of HAE attacks with an…

Thanks Jon. I'm pleased to discuss the details of our first quarter 2018 financial results. My comments are focused on BioCryst is a standalone company and do not reflect the proposed impact of the BioCryst Idera combination from our pending merger. The exception to the statement of course relates to BioCryst incurred merger expenses that have been reported thus far. We closed the quarter with approximately a $138 million in cash and investments. This capital is expected to provide liquidity for us through September 2019 and importantly beyond the reporting of Zenith-1 and APeX-2 clinical trial results. We are pleased with our progress in the study thus far and are thankful that we have a cat runway extending beyond these very important data points. Turning to Slide 12, our revenue for the first quarter of 2018 decreased to $4 million from $9.4 million recorded in the first quarter of 2017. The decrease was primarily due to $6.1 million of revenue derived from 2017 events that are somewhat infrequent, that is events we do not expect to normally recur on a quarterly basis and did not recur in 2018. Those events were a $2 million milestone payment related to RAPIVAB Canadian approval as well as $4.1 million of royalties derived from Japanese government stockpile. While we do expect the Japanese government and other governments to stockpile RAPIVAB because of its unique product profile, the timing and amount of these transactions is difficult to predict due to the relevant government's appropriation and stockpiling processes. First quarter 2018 R&D expenses increased to $18.4 million from $16.8 million incurred in the first quarter of 2017. The increase resulted primarily from additions in R&D personnel to support the evolution of all of our programs, as well as increased spending on HAE surrounding the ongoing APeX-2,…

Thank you Tom. I'd like to conclude by providing a brief update of our previously announced proposed merger with Idera. We have spent the last several weeks engaging with shareholders on strategic and financial merits of the transaction, which will create a new company to be called [Valencia]. We continue to be very excited about the opportunities for growth and stockholder value creation from this combination, as well as its many compelling benefits that can be delivered on behalf of the patients and employees of both companies. Together we will create a more competitive Company focused on rare diseases, with many more strategic opportunities to enhance stockholder value. Among other things, the combined company will be able to integrate and capitalize on both BioCryst and Idera's separate and complementary talents and expertise to successfully commercialize late stage development candidates and expand the number of rare disease targets that can be advanced into development. [Valencia] will have a more robust product pipeline led by two Phase 3 programs, two Phase 2 rare disease programs and a variety of early stage programs and supporting assets giving us more short-time goal and diversifying risk by combining synergistic discovery engines with enhanced development opportunities. This mean, we'll have the ability to leverage both structured guided, small molecule design and nucleic acid oligonucleotide chemistry within one organization. We believe the combination of small molecule and oligo chemistry may create more effective and potentially unique treatments for rare diseases, ultimately allowing us to expand the number of rare disease targets that can be advanced into development. For example, oligonucleotide chemistry primarily targets the kidney and the liver, however, by combining BioCryst small molecules with Idera's oligo's, we may be able to deliver oligo's to other target organs in the body. We believe this potential creates and exciting growth opportunity by establishing a unique and broader platform to pursues, in other words, more opportunities for success that are differentiated. Lastly, the combined Company will have increased financial strength and flexibility, making it well positioned to fund internal clinical development, discovery research and commercial launch preparation efforts. As you know the transaction is subject to approval by the stockholders of both companies. We invite all stockholders of record as of May 28, 2018, to join us at our special meeting to vote on the proposed merger on July 10, 2018 at 10:00 AM Eastern. We continue to work towards completing the transaction, so that we can deliver the benefits of the combination to employees, patients and stockholders. We are also looking forward to the new clinical data on Idera's IMO-2125 program, which will be presented at the American Society of clinical oncology meeting in Chicago on June 4. We remain as confident as ever about the financial and strategic benefits that this combination will deliver and we'll continue to keep you updated on our progress. That's it for our prepared remarks. We will now open it up for your questions.

[Operator Instructions] Thank you. The first question is from Brian Abrahams of RBC Capital Markets. Your line is now open.

Hi there, thanks for taking my questions. A question on the HAE program and then couple on the proposed merger. I guess on the starting with the 7353 on the Zenith study, with enrollment there ramping up. Is there anything you can say about maybe what you're observing on a blinded basis in terms of attack rate and safety that gives you confidence that this study will be able to show - clearly show benefit for 7353, as well as confidence in the GI tolerability of the high dose?

Hi, this is Bill. Hi, Brian. Thanks for the question. The oversight of the study of course is blinded as you pointed out. We have looked into the operational compliance as fixed from both the investigator and patient perspective. And just as a reminder the events in this study are treated at home and that's the modern era of self-administered care for the treatment of acute attack in hereditary angioedema so that the patient, so attacks need to be qualified for the experimental treatment that's done over telephone with site investigator. And that's going well. The patients need to fill out a diary that's going well. So from the point of view of gathering the data we need to analyze and come to a conclusion of that whether the drug is effective. I think we feel pretty confident that the operational aspects of the study delivering exactly what we will need. So that's going well; we haven't had any site issues.

Great. On the proposed merger, Bill, you noted and that you're expecting operating expenses to be in the higher end of the range in part due to merger related costs. Can you talk a little bit more specifically about that maybe quantify that to some degree? And what we should be looking for going forward if the merger were to go through in terms of those costs potentially washing out, as well as kind of the latest updates on potential synergies from a financial standpoint and the cash needs of combined company versus BioCryst as a standalone?

Sure, Brian. It's Tom. So first of all, the merge related costs were just under $5 million, $4.7 million. And in regards to - the up been in the upper end of our operating expenses ranges, there are two factors that really contributed to that. One is the aggressive advancement of predominantly our HAE program but also some of our pre-clinical program. So that's moving as quick as or quicker than what we anticipated in our budget. And obviously when we did our budget we didn't anticipate any due diligence and merger related costs. And so between those two factors it pushes you into the upper end of our forecasted ranges. In regards to the cash runway for both organizations, I think obviously I can speak for BioCryst, but I've also heard my counterpart at Idera, and both organizations have cash through September of 2019 as of the most recent public reporting. And they've also mentioned that they expect $20 million in synergies in year two and a total of $30 million in year three. So I think it would be inappropriate to discuss what the combined entity would look like because we're still going through the integration procedures. And I'm sure that will take some time after the deal was closed to come out with some public information.

So let me just add Brian, in my prepared remarks I talked about some of the financial flexibility that the new company will have, and that comes in the form of stuff that what Tom and I would categorize as more likely in the short term and then some stuff that a bit further off that's a bit more substantial. So in the bucket of more likely on that Idera side, there is opportunity that they've gotten from the sale of warrants that they've brought in additional capital. We got the opportunity with this procurement contract to bringing additional capital. There is ability to refinance the mid cap because we're assuming in that runway of the combined company that we would have to pay that back. And so refinancing that is something that we're relatively confident that we'll be able to do. And then there is couple of other things that Idera is working on that could bringing additional capital all together that somewhere in that $50 million to $60 million range roughly. And then the longer term is what we've talked about before where it's really clear that 2125 to really be able to take advantage of using it in a number of different tumor types requires the financial strength of a much bigger player. And so there is an interest level from strategic players in the space. And we remain confident that there could be a license deal that could bring in both an upfront payment and milestones that we think could be substantial and helping fund the future of the company. And then we've also talked about the ability to out-license 7353 in Japan. And Bill this month will be heading to hopefully finalize the development plan for Japan with PMDA. And we'll be working shortly after that to start our conversations with partners in Japan. So those things are bigger chunks that we think can really make a difference in funding the launch of 7353, funding clinical development of other programs as they advance and funding the research.

That's really helpful, thanks Jon and Tom. Sorry I misspoke I meant that question for you, but I do have one more question for Bill if I may. I guess what are the key things that I guess what we should be looking for coming out of the 2125 data at ASCO that might influence I guess the rationale and consideration of the merits, the risk profile the potential scientific synergies of the merger? And I'll hop back in the queue. Thanks.

Sure. My understanding is that there'll be an update of the 2125 plus ipilimumab of their ongoing Phase 2 experiment in melanoma. And they had an impressive response rate. So an update on the response rate and the durability of the responses the key items. I think that our review we were pretty satisfied the psyche profile of the combination is similar to the psyche profile of ipilimumab alone. And that progress on that study is going to be really interesting to see. I think in the market research that we took it independently at the time that we did our diligence the oncology community feedback was very clear the response rate in people who have failed already checkpoint inhibitor of about double the response rate you would get alone which is [Indiscernible] to say would be very impressive. And we value the asset taking that into account with overall response rate of 30% which is a lot lower than they initially saw in their original presentation. So I think they are the main things we will be looking forward to see an update on.

And yes you go from 10 patients to 21 patients, so much larger dataset that gives you more confidence that what you're seeing is real. So we're looking forward to that data coming out on June 4th.

Thank you. The next question is from Liisa Bayko of JMP Securities. Your line is open.

Hi, congratulations on getting the kind of Phase 3 design up and going and looking forward to the merger completing. Just a question about the Phase 3 actually what kind of patients are you going to be targeting for this for the Phase 3 in terms of sort of background rate of you know what-?

Yes, hi, Liisa. Again thanks for the question. So because the study is a lot longer than APeX-1. We've been able to liberalize the eligibility criteria on the tech right. So around about one month or so. In other respect the eligibility criteria are typical of the clinical trial, people have to be in otherwise good health and be able to comply with study requirements to study visits taking an oral medication, filling out diaries, all of that is actually clinically important to running the studies. So not every patient with hereditary angioedema able to do those things in various circumstances, but in general that's a broad in U.S. at adult and at a lessen population of the sort I described.

I would add to that Bill and his team has learned a lot from previous trials that we've run. And so the screening process and just making sure that we know that these people have HAE number one and understand their overall condition. And we're knocking out people that don't qualify and keeping people that do. I think we're getting much better at that. We were good at it before but I think we're getting even better and that's critical when you're in a Phase 3 study.

And will you have patients that have been on some of the other prophylactic medication in terms of wash-up here, how does that work?

Sure I think it's --the individual patient choices about their medical care with their physician. We don't influence and we don't try to influence. We can't for obvious reasons. We can't have other prophylactic medicines given during the study. Also for obvious reasons we have in all of our studies and will continue to allow and insist on the availability of acute medicine to treat attacks one or other of the acute modern medicines that are specifically targeted for HAE acute attack treatment. So there will be a whole range of diversity experience with prior therapies and we see that in our other studies. We expect to see the gain here with people who had experience with many of the prophylactic therapies already that are on the market.

She had a question about washout.

Yes, the washout is determined based on the half-life of the drug. So for example, if people have been on antigens before that take a while to washout. So there is an adequate washout period designed for each of the prophylactic occasions. And during the screening process they can't, there is a prospective screening element here as well. I don't come to straight into the randomized part of the study. So during the prospective screening portion they can't beyond any prophylaxis either.

Okay, that's helpful and makes sense. Can you give us kind of run through your assumptions in terms of like from here the prevalent terms of timing and so on and so forth?

Sure. I think we haven't changed their guidance on that. So our planning takes into account our best estimates of how long it will take to recruit and run the study. And also how long it will take to recruit and run an APeX-S safety program, because both of those combined are important. There is also maturing [indiscernible] study that will read out in the middle of next year. So all of those things combined as Jon said before lead to an NDA timeline in the second half of next year. I think from the point of view of when we will get a read out for the 24 week efficacy and safety analysis of APeX-2, we anticipate that before the middle of next year.

Thank you. The next question is from Maury Raycroft with Jefferies. Your line is open.

Hi, good morning and congrats on the progress. To start for Zenith, if you can talk about the baseline screening and how much history you have on patients coming into the study? If you can provide any general perspective on the heterogeneity in the baseline attack rates between patients?

Interesting question, thanks Maury. I think for Zenith, it's a very special study because, a, it's not Prophylaxis and b, what we're doing is seeing with our need intervention with our oral Kallikrein inhibitor kind of accelerate the recovery back to normal once you have an attack. So the sorts of things I measuring things like visual analog scales, the severity and the symptoms during the attack and how quickly they're resolved. For that study, clearly if you're going to swallow an oral medicine to treat the attack the type of attack is important and if you vomiting and then you can't swallow an oral medicine for example. So as I mentioned before, each attack has to get qualified. There will be a whole range of heterogeneity in terms of historical attack frequency. It's pretty liberal again. It is taking time for people to go through a total of 3 qualified attacks on study. For example, if you know the physicians is not file report 2 o'clock in the morning and they don't want to call the physician and that particular attack why get treated with an experimental medicine, that's probably the commonest reason and that's just - it's not a suitable time to do it. So that's factored into the estimates the Jon mentioned before. We are very confident and we'll be able to report at the top one result in the third quarter. But it does take time to people to get through three attacks and go through the process of calling a site investigator having a qualified and taking the medicine. And then operationally as I mentioned all of that's working; it's just taking some time.

Okay, very helpful. And for the 3Q update for Zenith, will that be top-line data in the press release or should we expect that at a medical conference?

You should expect that in a company announcement and in the past we've done that in a fair amount of detail, each time that we've had top line results coming out of it on very important studies.

Got it, okay. And then for the safety study, is the FDA or EMA, could you specified when you should do analysis for the safety study and when you all disclose, if you'll disclose results from those analysis?

So, the safety studies an open label studies, so there is no blinding involve. Each subject is treated with active agents and we accumulate safety data for the entire duration of the study, which by the way we'll continue after we filed the NDA. And we'll keep patients on the drug until it's commercially available and continue to get additional safety data. The timing of the analysis is that once we seeing the efficacy data we'll firm up that timeline for the NDA submission and then do a cut of the safety study to put in to the NDA. And there is traditionally a safety update, 60 days, 90 days after the NDA submission. So there is nothing in particular that the regulations are guided about that that just stated way of doing business.

Thank you. The next question is from the Serge Belanger of Needham and Company. Your line is open.

Hi, good morning. Couple of questions on 7353, you talked that the APeX-2 will most - initial recruitment will take place in the U.S., while APeX-S will recruit from the EU. Just wanted your thoughts on that strategy and what kind of the makeup between U.S. and EU patients, do you expect in the final enrollment numbers of the APeX-2 study?

Yes. So, let me just clarify Serge, this is Jon, on what we said in terms of priority. So, priority is getting the first half of the APeX-2 fully enrolled, and so what we've said is that the U.S. sites will only be used for that until that is completed. Then those patients of course will be rolling over into the second 24 weeks, which qualifies for additional data for the safety study. And once we've completed patients in the first 21 weeks, we will open up APeX-S to the U.S. as well. We are starting APeX-S as a result of that. We are starting APeX-S in Europe and that works out nicely because we can't reuse patients from either APeX-1 or Zenith in APeX-2. And so but we can enroll an over an APeX-S. So that's largely where that enrollments coming from currently. And then we will expand in addition to the U.S. when the first 24 weeks is completed, we'll also expand over the coming quarters other regions beyond Europe.

Serge, if you thoughtful to the applications for marketing and the U.S. and Europe, our anticipation are that both studies will have patient representation for both regions.

Okay. Thanks for the clarification. On Zenith-1 you expect the 715 mg cohorts report in the second half of 2018?

No, we upgraded that actually to the third quarter of 8-K.

So given your experience with that cohort and a smaller numbers of the two additional cohorts what do you think the cadence for the other cohorts to report in terms of timing?

Our plan is just to a file analysis when the study is finished and that will be next year.

Okay. We're going to do a part-by-part, so it will be the first with the 36 patients in the 750 milligrams cohort and then a final analysis of all three cohorts. And we're - like I said, we're 80% enrolled, we are already randomizing in the last cohort to 250 milligrams dose, so things are moving along at a good pace. The only tricky part is that you going to have patients have three attacks, following for three attacks and our experience thus far is it that takes about four months.

On average.

On average, yes.

So this - if you remember when the study started that was about middle of last year. So I think very confident that we'll report the final study results next year.

And one last question on RAPIVAB, do you expect any government stockpiling from this recent EU approval. And can you just give us I guess a quick history of the U.S. government stockpiling history of with RAPIVAB I think there was an order I think in 2009 or 2010?

Yes. So let me take that. So with regard to Europe, I don't think it hurts to have European approval, so but it's hard for me to predict anything around European stockpiling. But we'll see how that plays out. With regard to the U.S. stockpiling, you're correct, in 2009 we sold to the government 10,000 five day courses that were purchased I think in November-ish timeframe at $22.5 million. Those will expire next year and so that's why there's pre-solicitation for procurement process has begun to basically replenish which is currently in the stockpile.

Thank you. The next question will be Gena Wang of Barclays. Your line is open.

Thank you for taking my question. I think the most of my questions already being answered. Just quick, the APeX-S, just wondering will you collecting any attack data from this safety trial?

Thanks for question. Yes, absolutely we will collect attack data during the study. It's not an efficacy study, but it will be of interest to see the pattern of attacks relate that to patients prior experiences and we'll monitor that during the study.

Yes. I think and important piece of information, Gena to is that, the way the protocol is design, we are initially enrolling patients at the 150 milligram dose, then we put forward in appointment and patients will be randomize to one arm or the other with the 110.

I see. So how frequent will you collecting the attack data and then at what point do you share that data with investors?

So the plan for analysis is what I mentioned before is we'll analyze this study when it's time to stock compiling the NDA. So there is a - the way the data is collected is using a patient diary. So that will accumulate during the study and we'll analyze that when the timing is clear on how we need to compile the NDA. We'll know that after it's got the 24 week efficacy analysis from ApeX-2.

Yes. Because there is a part of the pivotal program and a part of the filing. We don't want to jump the gun on anything and so as Bill says, we'll report that data once we have done the cut submitted.

Okay and then one question regarding Zenith-1. So the top line data we'll expect in the second half this year, what will be your definition as a successful outcome?

That's a really interesting question because it's very worthwhile to look at how the prior studies of acute attack treatments were designed and reported. And people forget there is a placebo response here and that indeed if you don't treat attacks of hereditary angioedema, they results spontaneously overtime, so they reach a maximum and then they go away. And in every study there is a placebo treatment of exercise. The difference between the active and the placebo at four hours for example. It's generally - has generally been the range of 30% to 40%. So I don't want to predict what we'll see because I don't know what we'll see. I can predict on the basis of the response to the prior question on this call that we'll be able to figure out what's going on because the quality of the information is going to be very high. So I think that what we're looking for here is clinical benefit from an oral medicine. That's a big deal when you talk to patients. And if they can avoid injecting themselves when they have an acute attack that would be important. There are going to be some attacks that won't be suitable for oral medicine like I said before, if you are vomiting than you can rule that out. If you're having a rapidly progressive laryngeal attack when you can't swallow, you're much better off with an injection under those circumstances. So I think that having an oral treatment for an acute attack will give patients choice. And most attacks in not in the categories that I just talked about. The vast majorities in are peripheral or not associated with vomiting or not associated with impaired breathing or impaired swallowing or constriction in the throat. So there are - the majority of the attacks if you could treat it with a simple oral liquid for example that would be a big deal. So I think that the bottom line here is I don't think there's a pre-specified success criterion. We'd like to see a treatment benefit. We'd like to see it that it's clearly different from the placebo effect. And we should be able to make a judgment in collaboration with our expert advisors about and with the patient advocates about whether that's important.

And I think if it's close to that 30% to 40% that Bill talked about with an oral treatment. I think we have a real advantage because what we hear from patients is the injectable burns and sometimes there's a breakthrough attack. So having an oral that lasts a long time I think is a really big advantage even if we can't treat all attacks.

Thank you. There are no further questions at this time. I'll turn the call back over to Jon Stonehouse for closing remarks.

So as always we appreciate your interest in our company. The main messages here are the trains are moving on time. The programs are advancing as planned. And we continue to push forward as we believe that the merger with Idera makes sense for shareholders, patients and employees. So thanks for your interest and have a great day.

Thank you. Ladies and gentlemen, this concludes today's conference. You may not disconnect. Good day everyone.