argenx SE

Good morning. My name is Rob and I will be your conference operator today. At this time, I would like to welcome everyone to the Argenix fourth quarter and full year 2021 conference call. All lines have been placed on mute to prevent any background noise. After the speaker's remarks, there will be a question and answer session. If you would like to ask a question during this time, simply press star followed by the number one on your telephone keypad. If you would like to withdraw your question, again, press star 1. Thank you. Beth Jojocko, Vice President, Investor Relations and Corporate Communications. You may begin your conference.

Thank you, operator. A press release was issued earlier today with our full year 2021 financial results and a recent business update. This can be found on our website along with the presentation for today's webcast. Before we begin, I'd like to remind you on slide two that forward-looking statements may be presented during this call. These may include statements about our future expectations, clinical developments, regulatory timelines, the potential success of our product candidates, financial projections, and upcoming milestones. Actual results may differ materially from those indicated by these statements. Argenix is not under any obligation to update statements regarding the future or to conform these statements in relation to actual results unless required by law. I'm joined on the call today by Tim Van Harmeren, Chief Executive Officer, Carl Gubitz, Chief Financial Officer, and Keith Woods, Chief Operating Officer. I'll now turn the call over to Tim.

Good morning, and thank you for joining our call today. We had a truly monumental 2021 and ended the year with the FDA approval of VivGuard, a first-of-its-kind FCRN blocker, for the treatment of generalized myasthenia gravis in adult patients who are acetylcholine receptor antibody positive. It was a milestone we had been working towards for many years, and we were so gratified to be able to honor our commitment to patients by bringing them a new treatment option. The regulatory momentum continued into 2022, with the subsequent approval of VivGuard in Japan just 34 days later. I cannot emphasize enough the work it took for our teams to make this happen seamlessly. I want to start our call today talking about our launch. During these first weeks, we have focused primarily on demand generation through education and awareness efforts. Keith will share some metrics later in the call, but we still have a lot to learn about our launch trajectory in the coming quarters. We are doing our best to characterize the state of the launch today, though it's fair to say it's still very early, and these are not necessarily metrics we will share on an ongoing basis, especially as we start to provide revenues during our Q1 earnings call in May. I have had the privilege of being on the road with many members of our field team since the start of the launch. At a high level, we are encouraged by the initial demand in our launch. We know that it is still early days and that we face the same challenges that we described at approval. COVID restrictions, the lack of a J-code, the need for physician education and better awareness, But eight weeks into the launch, we are cautiously optimistic and trending well against our plans. I have also been encouraged by the feedback I am hearing firsthand from our physicians, all of which is consistent with many of the messages we shared leading up to approval. On slide four, for example, the unmet needs faced by GMG patients for new therapies is significant. and we are seeing real demand. The challenge for our sales force has been demonstrating its sense of urgency during a time when patients do not see their doctors regularly. We also see physicians rethinking how to treat their patients based on the advocacy and safety profile we demonstrated in ADAPT. And finally, doctors applaud individualized dosing and the VivGuard label, which allows them the flexibility to dose based on clinical evaluation. In MG, where every patient is unique and experience the disease course differently, an individualized approach makes sense to physicians. We believe that the treatment cycle approach will accommodate the majority of our patients We also want to consider the individual needs of patients that may require alternative or more continuous dosing, and to have data should we get questions from providers on this topic. We started a Phase IIIb trial called ADAPT-NXT to evaluate additional dosing schedules that physicians could use to further individualize the DIVGAR treatment approach. As this is a typical Phase IIIb trial, we will not be providing additional updates on the study outside of an upcoming medical meeting. In general, we want to have the most complete offering for patients and physicians, whether on a dosing schedule or around formulation, IV or sub-Q. We continue to believe that having both an IV and sub-Q option will be important to capture variability in patient and physician's preferences. Slide five. Our Phase III ADAPT SUBQ non-inferiority trial is on track to read out this month, evaluating SUBQ-Abgatigamot, which is co-formulated with Halozyme's validated enhanced technology. In this trial, we aim to bridge IV to SUBQ based on PD effect, specifically IgG reduction at day 29. We designed our innovative bridging trial based on a few key points. First, we observed in our clinical trials a linear correlation between IgG reduction and clinical benefit in GMG. We also see a consistent PD effect with abgartigamot, whether in healthy volunteers or GMG patients. The disease biology of GMG does not affect PD. And actually, we have seen this in all indications we have studied so far. And finally, in our Phase I study of sub-Q F-corticumab, we observed an identical PV effect with a fixed dose of 1,000 mg sub-Q as with 10 mg per kg IV. Beyond the non-inferiority primary endpoint, a depth sub-Q will capture additional safety efficacy, and PKPD data in the secondary endpoint analysis, which will be important for our commercial team. ADAPT-SUBQ also serves to satisfy our safety database requirements for SUBQ-EFGAT-TIGEMOT. We enrolled more than the 50 patients required for the primary endpoint analysis and allowed ADAPT open label extension patients to roll over to the ADAPT-SUBQ trial. We expect to be able to give you an update on timing of our BLA filing when we report top-line results. ADAPT-SubQ is the first of our near-term data milestones. We also are on track to share results in the second quarter from the advanced trial evaluating IV abgartigamot in primary immune thrombocytopenia, slide 6. We designed our Phase III advanced trial based on the results from our Phase II and benchmarking of peer ITP trials. In our Phase II, we had ambitiously dosed patients for just four weeks while monitoring platelet count out to 21 weeks. We learned from this trial that more chronic dosing is required in this population. Even with the limited drug exposure, we saw responses across patient types in a very refractory ITP population. These results are published in the American Journal of Hematology. We also saw a high placebo response in our Phase II, which, in looking at the trials, is very common in ITP given the fluctuating nature of platelets. In our Phase III, We are dosing patients weekly for 26 weeks with the potential to push the cadence to biweekly dosing based on a stable platelet count. We are measuring the primary endpoint between weeks 19 and 24 where a patient has to have a stable platelet count, meaning over 50,000 platelets per microliter in at least four of those six visits. By managing placebo response with this transient endpoint, we are also setting the efficacy bar high for our treated patients. It will be important to focus on the delta between response in the active and placebo groups. The secondary endpoints will also be important with the advanced readout, including safety and tolerability, cumulative platelet count, bleeding events, and quality of life data. This will show a more complete picture of where FGAT-Tigamot could play a role in ITP. We hear from physicians that there remains a high unmet need in ITP and that long-term response rates are not satisfactory. Patients typically cycle through treatment options, including through multiple TPO's in order to maintain a stable platelet count. Our hope is that we can break this cycle And if an ITP patient fails or relapses on an initial TPO, they will be in a position to try Avogadigamab before a second or third TPO. You can see that we have a catalyst-rich first half of the year between our launch progress and these two data readouts. It's a busy time, but also a very exciting time to finally have our teams in the field engaging with physician customers and serving patients. I'm going to turn the call to Keith, who will provide more details on the VivGov launch in the U.S.