Edited Transcript of ARNA earnings conference call or presentation 8-May-19 8:30pm GMT

Arena continues to make strong progress on all fronts: clinical, operational and financial. As you may recall, during the first quarter, we delivered positive open-label extension data for etrasimod in ulcerative colitis, closing United Therapeutics deal, securing a strong cash position and continued scaling the enterprise, including building our commercial and medical affairs team in Boston to deliver in 2019 and beyond. We believe we are uniquely positioned to continue to deliver results for patients and shareholders with our potential best-in-class products, a world-class team and a strong balance sheet.

For etrasimod, we are moving to initiate a Phase III program in ulcerative colitis midyear, rapidly advancing our Phase IIb/III program in Crohn's and our Phase IIb program in the atopic dermatitis. For olorinab, we are progressing a Phase IIb trial for gastrointestinal pain associated with irritable bowel syndrome, or IBS. And additionally, we continue to move other programs forward in our pipeline, including filing an investigational new drug application, or IND, for our preclinical asset APD418 for decompensated heart failure in the second half of this year.

So let me start with etrasimod. Etrasimod is a thoroughly characterized, in-house developed, next-generation, once-daily, oral S1P modulator with unique and best-in-class receptor selectivity and pharmacodynamics. It is the only next-generation S1P modulator and has the potential to be the preferred oral option for patients suffering from a broad range of (inaudible), T-lymphocyte-mediated immune and inflammatory disorders such as IBD. As is our practice and as we get closer to the initiation of trials, we'll disclose it on the details.

So with that, I will turn the call over to Preston Klassen to walk through the Phase III ELEVATE UC program. Preston?

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Preston S. Klassen, Arena Pharmaceuticals, Inc. - Executive VP of Research & Development and Chief Medical Officer [4]

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Thanks, Amit. As a reminder, last year, we delivered highly positive results from our Phase II OASIS trial of etrasimod for the treatment of moderate to severely active ulcerative colitis, or UC. And the patient population or a high proportion of patients at 40% had already failed the previous biologic therapy. We believe these Phase II data demonstrates that etrasimod has the potential to be a best-in-disease products for UC, and IBD continues to have a large unmet need, highlighting the opportunity for etrasimod to make a real difference to patients. And we are pleased today to provide additional detail on the Phase III clinical program in UC, which will be branded as the ELEVATE UC program.

Before I walk through the details, we developed the ELEVATE UC program with the following goals in mind: A trial design that is appropriate to meet global regulatory requirements for approval, effective use of enrolled patients to speed time-to-market and targeted endpoints and other design elements to produce a competitive label for payers and providers, ultimately delivering a product that offers sustained and market-meaningful, long-term safety and efficacy to patients in a once-daily oral therapy.

We believe that etrasimod and the ELEVATE UC program will allow us to meet these imperatives. The etrasimod global Phase III ELEVATE UC registrational program will consist of 2 key trials to evaluate etrasimod 2-milligram, once-daily in subjects with moderately to severely active ulcerative colitis. The first trial is ELEVATE UC 52, a treat-through trial design with a 12-week induction period and seamlessly followed by 40 weeks of maintenance for a total 52-week exposure. And the second trial is ELEVATE UC 12, which is a confirmatory 12-week induction period trial.

We plan to conduct additional studies to provide direct evidence and differentiation and value for health care providers and payers. These trials will elucidate the safety, efficacy and convenience benefits of etrasimod, particularly in the context of biologic and broadly immunosuppressive oral treatments. For competitive reasons, we will not go into specific details on these additional trials at this time, but we will provide those details when we are closer to initiation.

Across each of the 2 pivotal studies, we will target a population that includes both patients who are naive to prior biologic or JAK inhibitor therapy and patients who have previously been on and failed or are intolerant to prior therapy with a biologic or JAK inhibitor.

We will ensure that the program enrolls adequate representation from both biologic or JAK naive patients and patients with prior exposure to give prescribing physicians the important guidance on what to expect when etrasimod is used either ahead of these other therapies or after other therapies have failed. We believe this program will maximize our speed to filing and provide a robust dataset to exhibit the potential benefits of etrasimod. And with that, I'll provide some additional detail on these 2 trials within the ELEVATE UC program.

ELEVATE UC 52 will be a 2:1 randomized, double blind, placebo-controlled trial to assess the efficacy and safety of etrasimod 2-milligram once-daily in subjects with moderately to severely active UC defined as a baseline 3-domain, modified Mayo Score of 4 to 9 with an endoscopic score of 2 or more and a rectal bleeding score of 1 or more.

This is a 1-year trial examining both clinical remission at 12 weeks, which is typically referred to as induction, and clinical remission at 52 weeks. The trial consists of a 28-day screening period and a 12-week treatment period, a 40-week treatment period and a 2-week follow-up period. We plan to enroll approximately 370 subjects. The primary objective of this trial is to assess the safety and efficacy of etrasimod on clinical remission after both 12 and 52 weeks.

The primary endpoint is the FDA-required, 3-domain, modified Mayo Score, which is similar to the primary endpoint in the Phase II OASIS study. And the trial is appropriately powered to achieve significance on the 12- and 52-week remission endpoints as co-primary endpoints at a population level.

In addition, we will be assessing several key secondary measures, including the efficacy of etrasimod on clinical response, symptomatic response and remission, endoscopic changes, corticosteroid-free remission and a total healing in these subjects at time points up to 52 weeks of treatment.

Other objectives include evaluation of etrasimod pharmacokinetics and a variety of exploratory biomarkers and the effect of etrasimod on health-related, patient-reported outcome measures.

We continue to expect to initiate the ELEVATE UC 52 trial by midyear, and we plan to have data in 2021. The ELEVATE UC program will be conducted in approximately 450 sites across more than 40 countries, and I will provide additional color on our plans to execute the program and meet these timelines in a moment.

The second pivotal Phase III trial is ELEVATE UC 12, also a 2:1 randomized, double blind, placebo-controlled trial to evaluate the efficacy and safety of etrasimod 2-milligram once-daily in subjects with moderately to severely active UC using the same baseline disease severity definition. This trial is a confirmatory 12-week induction study and consists of a 28-day screening period, a 12-week treatment period and a 2-week follow-up period. ELEVATE UC 12 will enroll approximately 330 subjects to assess the efficacy of etrasimod when administered for 12 weeks on clinical remission, again, using the same 3-domain, modified Mayo Score endpoint for remission. Secondary measures in this study are similar to those that I mentioned as part of the ELEVATE UC 52 trial.

We plan to conduct the ELEVATE UC 12 trial across the same global trial site network of approximately 450 sites developed for the ELEVATE UC 52 trial, and we plan to stagger enrollment to optimize conduct of the 1-year trial and ensure that the confirmatory 12-week trial is not rate limiting to completion of the program to enable NDA submission. I will speak to you additional aspects of the trial execution in a moment.

Importantly to both studies, after participation in the main trial, enrolled patients will have the opportunity to move into an open-label extension trial from which we'll gather additional long-term safety and efficacy information.