Good morning. My name is Jennifer, and I will be your conference operator today. At this time, I'd like to welcome everyone to the Biogen First Quarter 2024 Earnings Call and Business Update. 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] Today's conference is being recorded. Thank you. I would now like to turn the conference over to Mr. Chuck Triano, Head of Investor Relations. Mr. Triano, you may begin your conference.

Thanks, Jennifer. Good morning, good afternoon, good evening, everyone, and welcome to Biogen's first quarter 2024 earnings call. Before we begin, I'll remind you that the earnings release and related financial tables, including our GAAP financial measures with a reconciliation to the GAAP and non-GAAP financial measures that we will discuss today are in the Investors section of biogen.com. Our GAAP financials are provided in Tables 1 and 2 and Table 4 includes a reconciliation of our GAAP to non-GAAP financial results. We believe that non-GAAP financial results better represent the ongoing economics of our business and reflect how we manage the business internally. We have also posted the slides on our website that will be used during this call. I'd point out that we will be making forward-looking statements, which are based on our expectations. These statements are subject to certain risks and uncertainties, and our actual results may differ materially. I encourage you to consult the risk factors discussed in our SEC filings for additional detail. On today's call, I'm joined by our President and Chief Executive Officer, Chris Viehbacher; our Head and President of North-America, Alisha Alaimo; our CFO, Mike McDonnell; and Dr. Priya Singhal, Head of Development is with us and will be available for the Q&A session. Chris, Alisha, and Mike will each make some opening comments and then we'll move to the Q&A session. And to allow us to get through as many questions as possible, we kindly ask that you limit yourself to one question. With that out of the way, I'll now turn the call over to Chris.

Thank you, Chuck. Good morning, everybody. Well, it is certainly great to be able to announce earnings per share growth in our first quarter. This is the first time in several years that the underlying business performance of Biogen has allowed us to actually demonstrate earnings per share growth, and that's a major achievement. We've clearly still got a lot of work to do, but I think it feels like we're turning the corner in the company. And with that, I'd like to actually take the opportunity to thank my Biogen colleagues. We have instituted an awful lot of change within the company and I'd like to thank them for their commitment, passion, and patience throughout this process. But I think you're seeing some of that change that has occurred now in the numbers. We have tried to bring a lot more focus and discipline to really putting our resources behind those things that do good and drive value. And one of the things that you may not see is that, there is an awful lot of reinvestment going on. One of my early bosses in my career once told me, you can't save your way to prosperity in this business, and that is absolutely true. And that's not really what we set out to do. The Fit for Growth project, which is, as you can see from the numbers, on track to achieve its $1 billion in gross savings and $800 million in net cost savings and by the way, [$100] (ph) million of increased cash flow as well by the end of 2025. But what we really tried to do was redesign the organization. We have been so focused as a business for decades on our multiple sclerosis franchise, and here we are launching four first-in-class new medicines and we really needed to make sure we're supporting those launches. And in fact, despite the cost reductions and margin improvements that Mike is going to go into in more detail, but behind that, there are hundreds of millions of dollars being invested in new launches. And while our overall expense in research and development has decreased, this focus has actually enabled us to increase the investment in those assets where we have the most conviction. So, this is much more than a cost-savings exercise. This has been a redesign and a change in our culture to a degree. So, let's look at some of these new launches. And obviously, the one that everybody is most interested in is LEQEMBI and if we can move to that slide. You can look at this in a number of different layers. Obviously, first, we're seeing really good quarter-on-quarter trends. As you've seen, the number of patients on drug has increased to 2.5 fold compared to where we finished the fourth-quarter. Our in-market revenue almost tripled in Q1 versus Q4 of last year, and that's obviously important. But the thing that really is important to me as I look at this is not so much just that. I've been in this business for 3.5 decades. I've lost count of how many launches I've seen, but this is an extraordinarily difficult launch, really because the amount of change that physicians are facing with this is really profound. And as I go around to hospitals and talk to doctors and talk to those who are seeing other doctors, it really becomes evident that there are an awful lot of challenges to getting that -- even that first patient on treatment. We were at one hospital, it was going to take -- it took them three months to get approval just to hire a nurse to help navigate the system. At another major medical center, they're having to develop a five-year business plan, just to be able to access the infusion beds. And when you look at some of the uncertainty around PET scan reimbursement, and although CMS had clarified that and a lot of the MACs have pulled it through, there was still a lot of difficulty getting that clarity all the way through the channel. You know why I'm really encouraged by when I look at these numbers is, when -- although there are a lot of challenges, it's a lot of time investment for physicians and I think a lot of those physicians to their credit are investing that time and not necessarily getting reimbursed for that, but they're getting it done. They're overcoming these challenges and barriers. And that is, I think, what is so important. They see the need when they look at patients who are accomplished people, who are loved by their families, and seeing this dreaded disease pull the patient away from that on a day-by-day basis. So, I do think we are seeing an awful lot of momentum here. And again, I think there's an awful lot of credit to the neurologists and to these centers to overcoming these challenges and I think that is going to allow us to continue to see quarter-on-quarter growth. It may not be completely linear, and Alisha will go into more detail on that, but it takes time to get these protocols in-place and even when you get the first patient, there has been a tendency that let's have a handful of patients so we get comfortable with the system. But then, once they've done all that, then, we're starting to see volume pull through. And one of the interesting things about this launch is that, generally, we look at revenue as a surrogate for demand. And here there's -- that linkage is not quite so clear because it has taken this upfront time before you see revenue pull through. And I think that's one of the other things we're now seeing in this first quarter is that, we're actually seeing a little bit more of that linkage between demand and revenue. And behind all of this, once those processes are in place, and once physicians are ready, there is clearly an underlying demand behind that. So, I think that has given us a lot of confidence to now invest more, and we have a 30% expansion in our US field force plan. But I would also say, this is a launch that really didn't start until 1st of September. And even then, you could argue we weren't fully in the mode of being able to launch because the PET scan reimbursement hadn't been cleared. But our US teams for both Eisai and Biogen have done an awful lot of work to look at the data from the first seven months of the launch. And really, we're now looking at redeploying some resources here and there as we see what's important and what's not. I think the teams are really working well together. And we have a number of new elements of our promotional mix that will start to come into play as we progress through the second quarter. So, from a Biogen point of view, I think it's too early to put out any forecast. We're going to be looking at those month-over-month new patient starts and the increase in revenue. But I would certainly say I'm extremely encouraged by the progress that has occurred. And if I could switch gears to another key growth driver, which is SKYCLARYS, and Alisha, again, will go into more detail and I think also just show investors how we're progressing versus other analogs because the rare disease market doesn't behave so typically as in other markets. There is always a catch-up population in rare disease. And so, it takes a while for that catch-up population to work through the system and then have a look at what's the underlying demand. Remember that these are not patients sitting in waiting rooms and that there is a huge amount of work that goes into finding patients. And I think that is actually one of Biogen's strengths. That's I think what gives me the confidence to continue to invest more because I do think there is a know-how within Biogen and that's one of the reasons we want to build out a rare disease franchise. But we've got 1,100 patients now on therapy in the US. That's a really significant number. But I'm also really encouraged by the launch in Europe. We've already got -- and remember, this drug was only approved in the -- at the end of January and yet we already have 300 patients on treatment. Now, you all know Europe. We have to go country-by-country to get reimbursement and we have early access programs, some of those we can charge revenue for, some of them we can't, but we have already submitted reimbursement dossiers in five countries in the US. So I think Europe will increasingly add to the revenue. It's probably more of a 2025 story than a 2024. But I think if I'm looking at the acceptance and the uptake, then, that launch is also off to a successful start. And we know that there are an awful lot of patients in Latin America and we've already submitted in Brazil, for example, submitting in Argentina. And I think that actually is going to be a major benefit and opportunity for us as well. Remember, there are no patients in Asia because this is a genetic disease that really affects people of European descent. And in fact, it was quite interesting. I was talking to a key opinion leader in Germany who is actually done genetic studies. And you basically just follow where the explorers went and that's where you're going to find the patients. So I think with that, let's dive in a little bit deeper and I'll turn it over to Alisha.

Thank you, Chris. Good morning to everyone that's able to join the call today. I'm Alisha Alaimo. And as Chuck shared, I lead our business in North America. This is a really unique period in Biogen's history with multiple first-in-class drug launches in the US, which gives us an opportunity to drive our return to growth. And for our team, it's also meaningful to support more people living with Alzheimer's, Friedreich's ataxia, and postpartum depression. We thought it might be helpful to provide a perspective on the market dynamics of the launches and share how we're seeking a tailored approach to help provide patients with access to our therapies. Let me begin with the Alzheimer's market. As Chris mentioned, we are seeing many major health systems across the country take a deliberate staged and phased approach, meaning, they are setting up their pathways to get patients started with diagnosis, treatment and monitoring. We believe we are now seeing a dynamic where some IDNs are turning the page and they are focusing on expanding and extending their model. In Q1, we saw several IDNs across regions scale their patient volume. Among our priority 100 IDNs, units more than tripled in quarter one compared to quarter four, which contributed to the overall estimated patients on therapy increasing approximately 2.5 times in quarter one versus quarter four. We believe this acceleration in new patients really began to emerge at the end of the quarter. For example, more than 20% of new patients since launch were added in March. Today, among our 100 priority IDNs, more than 80% have approved LEQEMBI through their P&T process and nearly 85% of those IDNs with approval have placed an order. Chris also mentioned that we're seeing more physicians gain experience with LEQEMBI. We saw the number of unique prescribers in quarter one double compared to quarter four. We believe that we're still in the early phases of unlocking the potential to treat a high volume of patients at the priority IDNs, and I thought it might be helpful to share some examples of these dynamics at the site level. There is one large health system in the Midwest that added LEQEMBI to its formulary in July of last year. Six months later, entering Q1, this system had ordered only 300 units. However, by the end of March, they had ordered 2,700 units. Similar to the example I just shared, there is also a health system in the Southeast that added LEQEMBI to its formulary in August of 2023. Five months later, entering Q1, this system ordered about 560 units. By the end of Q1, this system ordered more than 1,750 units to treat their patients. For context, a local neurologist network in that same region ordered 3,000 units through the same time period, perhaps because they've been able to scale their processes to treat more patients. However, we believe this well-known Southeast IDN is planning to move beyond their flagship side of care to treat at multiple locations, which is another example of the expand and extend trend at the IDNs. We believe many systems just now appear to be completing the staging phase, and we think the recent trends observed support our continued belief that LEQEMBI represents a significant commercial opportunity over the mid to longer term. With access and infrastructure progressing and patient volume accelerating, we believe this is also the right time to expand the field force. Biogen leaders are working to hire a customer-facing field team, which will join Eisai. Simultaneously, to activate the patient community, Biogen and Eisai have launched new direct-to-patient and caregiver omnichannel marketing campaigns. These digital programs and point-of-care resources are focused on the already diagnosed patients, who we believe are under the care of a neurologist. With these promising signals emerging, we look-forward to providing more updates in the future. Now moving to SKYCLARYS. We believe we're driving strong performance with the launch as we continue to exceed market penetration rates of most rare disease launch analogs. As of April 19, we now have over 1,100 patients on therapy. With an estimated 4,500 addressable Friedreich's ataxia patients in the US, we have achieved 24% market penetration, which exceeds our own strong SPINRAZA launch. As is typical with rare disease launches, we believe we are now moving beyond the catch-up population, to reach additional patients who previously received a diagnosis of, or are suspected to have Friedreich's Ataxia. Though patient numbers may be uneven, we anticipate adding patients each month. Last quarter, we shared how we've integrated some of our sophisticated rare disease capabilities to drive improvements in access, logistics, and patient support. Notably, our market access team continued to make progress by securing favorable policies in quarter one. Today, nearly 80% of all US pharmacy lives now have SKYCLARYS reimbursement. These patient support and access efforts are critical to help patients start therapy as soon as possible, and remain on treatment for the long term. With a meaningful foundation of patients on therapy, we are focusing on two key areas in this next phase of our launch. First, educating community neurologists and PCPs about Friedreich's ataxia and SKYCLARYS, and second, engaging additional appropriate patients. I'll begin with our focus on HCPs. Remember with Friedreich's ataxia, in addition to patients being concentrated at the top centers of excellence, we believe they are also being treated in the community. To support these physicians, we've expanded our field footprint and we are using AI to analyze data to help reach the HCPs who may have untreated patients, with insights into the relevant sites of care and when patients last engaged with their physician, we believe we can help more patients even sooner. And with genetic testing, we anticipate patients can confirm a potential diagnosis and determine if SKYCLARYS is a treatment option. As far as our patient activation focus, we are encouraged by real-world experiences that patients are sharing on social media as, in our experience, these stories can help other diagnosed patients. Many of these stories about the impact of SKYCLARYS include reports of slowing of disease progression and in some cases, even an improvement in their symptoms long term. In addition to these organic stories, we anticipate launching our SKYCLARYS social media campaign soon. So, we believe we're off to a strong start, but we know there are more people living with Friedreich's ataxia that we can help, and we look forward to supporting them, which now brings me to ZURZUVAE. As Chris mentioned, we are encouraged by the performance of the launch to date, and we think we are seeing several positive trends with providers, patient experience, and reimbursement. First, let me begin with providers. Across multiple physician types, we believe many providers are demonstrating an urgency to treat. Notably, OB-GYNs led overall prescribing in quarter one, which we believe is encouraging as they are often the first to see PPD patients. Furthermore, breadth of adoption has continued to grow. In March, nearly double the number of HCPs prescribed ZURZUVAE compared to just January. We've seen that some early prescribers require only a few calls before they treat. Keep in mind that ZURZUVAE is a scheduled product available through a specialty pharmacy. While we believe psychiatrists are generally familiar with working with specialty pharmacy, this could be a new process for many OB-GYNs. We're working to educate these providers on the steps required, so that they can support their appropriate patients. Second, some HCPs have early experience with ZURZUVAE, have shared that some of their patients reported significant improvement in depressive symptoms within days of starting treatment. Several patients are sharing their personal 14-day treatment experiences on platforms like TikTok, and we believe their courage to tell their story will help educate other women living with postpartum depression. Third, we believe we're making good progress with government in commercial access. Many payers already have policies in place, the majority of which have been favorable, while some others continue to cover ZURZUVAE, even without formal policies in place. Two of the three national pharmacy benefit managers are providing coverage for ZURZUVAE without overly burdensome restrictions. We are in active discussions with the third national PBM as we await their decision. And while Medicaid tends to take longer, almost half of the states, including several of the largest, accelerated reviews into quarter one, which we believe is unusual for a process that can typically take-up to a year after FDA approval. We are encouraged that approximately two-thirds of Medicaid lives with published policies appear to have minimal access restrictions. We anticipate the remaining states will review coverage throughout 2024, and we will continue to support their reviews as much as possible. Before handing it over to Mike, I want to underscore that we have an important responsibility to help people living with Alzheimer's, Friedreich's ataxia, and postpartum depression. And we are working with urgency to help these patient communities. We believe we're making significant progress in that mission, and we look forward to continuing to share updates with you. With that, I'd like now to pass it over to Mike.

Thank you, Alisha, and hello to everyone. I'd like to start with a high-level overview of our financial profile, and how we are seeing this progress in the context of our Fit for Growth program. We maintain a sharp focus on improving profitability as we endeavor to return the company to not just EPS growth, but revenue growth as well. Please note that any financial comparisons that I make are versus the first quarter of 2023. Regarding our top line, our four recent launches contributed revenue in the first quarter, which more than offset the 4% decline in our MS business. And as we noted during our previous earnings call and at a recent webcast investor conference, we expect that this year's revenue will be skewed more towards the second half of the year, and we expect this to be due to both the timing of shipments for SPINRAZA outside the US, as well as the expected growth profiles for our recently launched products. On gross margin, we saw improvement of 5 percentage points in the quarter as our revenue mix has shifted. This is due to increasing high-margin product revenue replacing lower-margin contract manufacturing revenue. We also had $45 million of idle capacity charges in the first quarter of 2023, and none in the first quarter of 2024. Our R&D prioritization and Fit for Growth initiatives had a clear impact on our non-GAAP R&D and SG&A expenses, which we refer to as core OpEx during the quarter, and that resulted in a 13% decrease year-over-year. These savings contributed to meaningful growth of our non-GAAP operating income of 24% year-over-year. Our operating margin was 31% in the quarter as compared to 23% in the first quarter of 2023. And while these are encouraging improvements so far, we believe there is still more work that can be done to continue to improve these metrics. Now, a bit more color on revenue dynamics during the first quarter. Total revenue was $2.3 billion, which was a decrease of 7% at actual and constant-currency. Our MS franchise revenue declined approximately 4% driven by competition and the usual channel seasonality that we see in the first quarter. Within MS, VUMERITY revenue grew 18% and benefited from global patient growth as well as some favorable channel dynamics during the first quarter. Regarding TECFIDERA in the EU, we have now seen most generics exit the market, which drove ex-US growth of 5% for TECFIDERA this quarter. We continue to believe we are entitled to market protection in the EU until February of 2025. And now, a quick double-click on our rare disease revenue for the quarter. SKYCLARYS delivered $78 million of revenue, including approximately $5 million in Europe, where we have launches in several countries underway. For SPINRAZA in the US, revenue was up 1% in the quarter, and we remain encouraged by the resilience here. SPINRAZA revenue outside the US declined 35%. The majority of this year-over-year decline was due to shipment timing in certain emerging markets. We continue to generally see stable patient numbers globally, and we would expect the shipping dynamic outside the US to largely normalize throughout the remainder of 2024. We also saw some modest negative impacts from competition and foreign exchange in the quarter. For the full year 2024, we expect global SPINRAZA revenue to decline by a low-single-digit percentage. ZURZUVAE delivered $12 million of revenue, which we believe is inclusive of some channel stocking in anticipation of increasing demand, which is common for any new launch. And lastly, contract manufacturing revenue was notably lower year-over-year, and as we reflected in our guidance for the full year, we continue to expect contribution from this line to be significantly lower than last year, due to completing a number of batch commitments in 2023. First quarter non-GAAP cost of sales was 22% of total revenue, and that's an improvement of 5 percentage points. As I previously mentioned, this improvement was driven by a more favorable product mix, as revenue from new product launches replaced lower margin contract manufacturing revenue, and it also was related to having lower idle capacity charges. We did not have any in the first quarter of 2024. First quarter non-GAAP R&D expense decreased $124 million, which was driven primarily by savings achieved from Fit for Growth, where we remain on track to achieve cost savings of $1 billion gross and [$8 million] (ph) net of investment by the end of 2025. We also saw savings as a result of our R&D portfolio prioritization, which has had a meaningful impact as we discontinued some programs and have focused our spend on areas we believe have a higher probability of success. Non-GAAP SG&A expense decreased approximately $33 million in the first quarter, and this was primarily due to $50 million of G&A-related cost reductions, which were realized in 2024 in connection with our Fit for Growth program, and that was offset by an increase in operational spending on sales and marketing activities in support of the LEQEMBI and SKYCLARYS launches. I will also note that the prior year included $31 million related to the termination of a co-promote agreement for our MS project -- products in Japan. All of this together contributed to non-GAAP operating income growing 24%, with non-GAAP operating margin now above 30% and improving and non-GAAP EPS growth of 8%. Next, a brief update on our balance sheet. We ended the quarter with approximately $6.5 billion of debt, $1.1 billion in cash and marketable securities, and net debt of roughly $5.5 billion. As of March 31, 2024, the $6.5 billion of total debt included $250 million of the $1 billion 2023 term loan, which was put in place at the time of the Reata acquisition. As of March 31, 2024, we had repaid $750 million of this $1 billion facility. The remaining $250 million is expected to be repaid during the second quarter of this year, so this quarter, earlier than our original expectation, which was by the end of this year. I'd note that this cash and marketable securities figure does not include a $437 million payment from Samsung, which we received earlier this month. We continued to generate strong free cash flow during the first quarter with approximately $507 million of free cash flow. So overall, our balance sheet remains in a strong position, with increasing capacity to invest in growth initiatives. And regarding our strategic review of the biosimilars business, at this point, we have not received an acceptable offer from a third-party. Our process remains ongoing and we will remain disciplined as we continue to explore all options including retaining the business. Next, I'd like to discuss our full year 2024 guidance ranges and assumptions. We are reaffirming our expectation of full-year 2024 non-GAAP diluted earnings per share of between $15 and $16, which reflects expected growth of approximately 5% at the midpoint of the range as compared to 2023. All of the previous assumptions to our guidance, including those you see on this slide, remain unchanged. I'd like to remind that we have potential R&D success milestone or opt-in payments associated with the upcoming clinical data readouts, and we have made an allowance for some of these potential payments in our guidance. Of course, whether or not they are paid will be dependent on the data and our resulting decisions. And finally, we just announced the completion of a sale of one of our two priority review vouchers for $103 million. At this point, we expect to earmark these proceeds for business investment, or to support business development opportunities as they arise. And in closing, we remain committed to our number one goal of returning Biogen to sustainable top and bottom-line growth, and creating long-term value for our shareholders. We will now open up the call for questions.

Thanks, Mike. Jennifer, can we go to questions?

Thank you. [Operator Instructions] Your first question comes from the line of Eric Schmidt with Cantor Fitzgerald.

Oh, hi. Thanks so much for all the updates and for taking my question. I guess on LEQEMBI and maybe for Priya, we had a couple of updates in the last month or so, the EMA delay on the CHMP recommendation. And also, I know this is your partner's doing, but Eisai announced that they couldn't submit for the subcu approval until they finished the immunogenicity study. I was hoping you could just update us on timelines for both of those initiatives going forward? Thank you.

Yes. Thanks, Eric. So maybe I can just start off by saying that we are working with Eisai to really provide patients with the optionality of a subcutaneous formulation. Our approach is entirely data driven. So we were very encouraged to see the bioequivalence we met last year and we shared that at CTAD. This was the most important milestone. Thereafter, we've engaged with the FDA. And currently, just to characterize how we are approaching this, we've split our strategy for subcutaneous formulation. First and foremost, we are working to submit a rolling submission for subcutaneous autoinjector for maintenance. This we're going to do at earliest. Eisai has already submitted a fast track application. We're awaiting that. And as soon as we get it, we will make the submission, while we continue to generate the data for the three-month immunogenicity that the FDA has required. Second, because our exposure with subcutaneous formulation was higher than the IV formulation, we believe it's in the interest of patients to optimize dose, and that will lead to more convenience. So, we are optimizing this dose and that is something that is already ongoing and is currently ongoing this year. In terms of timelines, if we get the fast track for subcutaneous maintenance, we will file immediately for rolling review, and that we expect would be in this year even if we don't get the fast track because we have completed the three-month immunogenicity data by Q4. Second, for the subcutaneous induction therapy, we expect that we would file by the first quarter of 2026. That is what Eisai has already communicated in their investor comments early March. I'd also like to remind us that we completed our intravenous maintenance filing by Q1 2024 as we [indiscernible]. Thank you.

Thank you, operator. Next question, please.

We'll go next to Paul Matteis with Stifel.

Good morning. Thank you for taking my question. I was wondering if we could get your updated perspective on business development as it relates to capacity, therapeutic area, stage of development, or commercial? And just in the context of this, how the kind of uncertain -- promising, but uncertain trajectory of lecanemab influences your appetite to execute on something now versus maybe wait a bit until 2025? Thank you.

Thanks, Paul. I think this year, we're going to be focused on business development to bring in some new assets, both into early-stage research and development. We have always called ourselves a neuroscience company, but the reality of neuroscience is that, this is a high-risk area. We don't always understand the underlying disease biology, the diseases progress slowly, that leads you to some very long and expensive trials. You can't often do a proof-of-concept study in Phase 2. And so, while we remain committed to neuroscience, my personal view is that I think that is to -- that is not diversified enough for a company of our size. And so, already last year, we signaled that we'd like to go into some adjacencies in rare disease. I think we actually have a tremendous commercial capability in rare disease. There are special commercial requirements, the need sometimes to support diagnosis, all of the hurdles with payers that have to be overcome and of course, finding the patients. And there are an awful lot of tools that I think we have to be able to do that. And then immunology, we've been an immunology company since the get-go since some -- MS is really an autoimmune disease. So, I think we'll use the opportunity with licensing collaborations to expand that. I think where our balance sheet is, if something really extraordinary came along, I suppose we look at it, but I don't think where we sit right now, we'd be thinking about doing anything this year on an acquisition front, not certainly of any size. But Mike, maybe you can talk to the balance sheet capability.

Yes. So, Paul, I would just comment that our balance sheet is in a very good spot. If you look at our net debt position at the end of the first-quarter, and then you pro forma that for the Samsung payment and the paydown that we'll make in the second quarter on the term loan, it's about $5 billion of net debt. We generate about $3 billion of EBITDA. So, it's only about a -- somewhere between 1.5 turns and 2 turns of leverage. So, we certainly could add another turn of leverage for something that we liked, at least temporarily, and we generate a couple of billion dollars of free cash flow per year. So, I think about it in the context of 2024 as maybe a $4 billion to $5 billion of capacity sort of number for things that we might be really interested in. And then, if you were looking at something more Reata-like, that's probably a little more logical, capacity wise in 2025 or beyond.

Thanks, Mike and Chris. Can we take the next question, please?

Yes. We'll go next to Salveen Richter with Goldman Sachs.

Good morning. Thanks for taking my question. For SKYCLARYS, could you speak to the 2024 outlook and any bolus dynamics that has impacted this? And specifically, you've talked being 24% US market penetration. How are you thinking about peak penetration in the US and then the expectations for pace of uptake in Europe and net pricing there? Thank you.

Alisha, you want to take US and I can follow up with Europe?

Yes. I think when you look at the US and the market penetration, and you probably saw in the analogs on the slide that the launch has gone very well thus far. And as I also said, we've made it through sort of the catch-up population. We have a lot of really good things in-place right now that we are launching in parallel to identify and hopefully get to the rest of the population. The way in which we think about this market though is, we do have two sets of patients. You have a set that are highly engaged with their physicians, and you have another set who haven't been engaged, probably over the last two to five years. We have enough data and analytics to understand exactly where these physicians are, and how the patients have moved through them. And so, with that, we are now identifying a lot of these offices, especially in the community who could have a patient or two that might be diagnosed with general ataxia, but not Friedreich's. And so, what I referred to earlier on the call is expanding the field force footprint. We have a very targeted approach to these offices in order to, again, increase the market penetration. Now, as you see with something like a SPINRAZA, we've also performed very well, and also have driven quite a good market penetration with that product, even though there's competitors in the marketplace. With SKYCLARYS, with no competitor really in the market, we expect to continue over the next several years to penetrate this for as far as we can go. We know that there are 4,500 approximate patients that could have Friedreich's ataxia. And so, what we're doing is planning everything that we can to get to as many of them as quickly as possible.

Thanks, Alisha.

Yes. And on Europe, in some ways the single-payer systems actually are really ideal for rare diseases. A lot of patients in the US, even if you have reimbursement, even if you have insurance coverage, there are an awful lot of hurdles that the US healthcare system imposes upon patients. And a lot of those, we don't really see in Europe. And so, I think we're seeing a rapid uptake. Again, there's -- there is a catch-up on population. So there's -- and there's a difference between patients on treatment and revenue-generating patients. So first, we have -- we have actually the commercial launch in Germany because we can get reimbursement relatively quickly. Other countries will come online as we go through the individual country reimbursement processes, but our objective is actually build up the patients. So there's a number who are on free drug at the moment through these EAPs, some of the EAPs you can charge for. So, it's going to be a little lumpy as we look at the revenue line. But I'd say we're extremely encouraged by the uptake of patients. And then, ex-US in Latin America, that could well be a story for 2025. I think you may see our first launch in Brazil in early part of 2025.

Great. Thanks, Chris. Can we move to the next question, please?

Yes. We'll go next to Umer Raffat with Evercore.

Hi, guys. Thanks for taking my question. I have one for Priya, if I may. I know there's the late-stage lupus readout with the CD40 ligand antibody this summer. I also realize the time point on this readout is week 48 instead of week 24. And I guess my question is, knowing that there wasn't a clear dose-response on efficacy in the prior trial, could you speak to how the B cell impact was different between doses and whether the prolonged duration could actually help the B cell impact on this upcoming readout? Thank you.

Thanks, Umer. We have looked at the Phase 2 study very carefully, and we have decided and we included the 48-week endpoint on BICLA for this Phase 3 study. And ultimately, we're looking for a meaningful change on the primary endpoint, and the key secondary endpoints for SLE such as severe flare prevention and patients achieving low disease activity. We also think that the BICLA is a sensitive, clinically meaningful composite measure of SLE disease activity, and requires disease improvement across all body systems with moderate or severe baseline activity without worsening and the need for escalation in background medications. So we modified the trial, we are -- we have refined the population, and we think that this is going to be really important as we kind of look forward to the readout. The other piece I think here to keep in mind is that we considered how we can modify the population for this study and get to an answer really quickly to bring potentially dapi to patients. So I hope that answers your question.

Thanks, Priya. Let's go to the next question, please.

We'll go next to Michael Yee with Jefferies.

Hey, guys. Thanks. I wanted to revisit SKYCLARYS comments. I know you said you were planning to add patients month-to-month. Can you just talk about the trajectory of SKYCLARYS this year as it relates to also any offsets like discontinuation rates, et cetera, et cetera, how does that factor into it? And also, will you book Germany revenues this year? So just talk about the dynamics of revenues for SKYCLARYS. And if I may sneak in one clarification. Priya said subcu induction filing for LEQEMBI Q1 2026. I just wanted to clear that's what she said? Thank you so much.

Yes. The outcome and the filing will be in that period, but we'll communicate more on this once we optimize the dose and we go forward.

Okay. And SKYCLARYS?

Yes. So for SKYCLARYS, it is quite complicated month-to-month, I will say, because you have patients, obviously, that we're getting via the start forms, which I will say for the highly engaged population we are pretty much maxing that out now. We absolutely know who they are and we've captured them through the physicians. But then, you're also going to have a discontinuation rate as you have noted, and you're going to have patients that are being pulled off the start forms, putting on to product. And then of course, you may have them miss a dose or two, right? So then, there's compliance. So month-to-month, it will be lumpy because you can say you add 50 patients, but then you have other dynamics going on in the patient population. But what our outlook is for the year, which I can't give you a specific number, is that we are going to continue to add every single month. We are able to find those patients in the community, and there are other puts and takes in those numbers. But at the end of the day, we will ensure that we are still leading the rare disease analogs and that we're going to generate market penetration.

Yes. And in Europe, we're booking revenue now for Germany and actually -- we've actually launched in Austria and the Czech Republic as well. And in some countries, we're actually able to charge for the early access programs in Europe and some of that revenue will come down too, but you probably see more full EU as a region revenue in 2025, but there will be certainly revenue contributions in 2024 from certain countries in Europe.

Great. Thanks, Chris. Let's go to the next question, please.

We'll go next to Colin Bristow with UBS.

Good morning and thanks for taking the questions. Maybe one on the LEQEMBI commercial setup. So, one investor concern and important feedback we've been hearing from physicians is around, there being less sales and marketing presence than perhaps had been expected. I heard in your prepared remarks you're saying you expect a 30% increase in the US footprint. Are you able to sort of quantify the current US commercial footprint? And was the 30% increase always planned, or was it based on some review that the current footprint wasn't adequate? Thank you.

Thank you very much for the question. If you really take a step back and look at how we strategically looked at this launch, we always said that we were going to do in a stepwise approach. We knew from the beginning that sites were going to take a while to get up and running. We had to wait for several indicators from CMS giving full approval and NCD being overturned for PET. And so with that being said, we didn't want to go out of the gate with a really huge field force that wasn't able to actually impact or penetrate the market. So instead, what was decided is we went in with a very focused approach. We focused on really the top accounts that we think handle the majority of the diagnosed patients, especially that are under neurology care. And we said once the market gets to a place where we think it's ready for expansion, then we will expand. Now, to your comment about physicians coming back saying they're not seeing a lot of sales efforts, I think, we also have to have really the context of getting these sites up and running takes a lot of effort. And you also don't want to have three, four, five different people going into these accounts to support. And so, we've been very focused on really getting the large IDNs up and running. Some of these centers that have come forward that really could move quite quickly, we got them up and running. And now as you see the expansion take place with the 30%, we are going to focus mainly on the large IDNs that are now opening up their expand and extend satellite offices, where they're now going to allow a larger cohort of patients to come through for diagnosis and treatment. And so, with this next phase of a build, which we believe we've done a lot of analytics behind it, and we've had a lot of third parties weigh-in on what is the appropriate sizing, we and Eisai believe that this is going to be the right footprint to drive the next acceleration of growth.

And let me just turn it to Priya for a clarification back to Mike Yee's question on subcu.

Thank you. Thank you. Just wanted to clarify that it's the outcome by fiscal year -- Eisai's fiscal year 2025, which is Q1 2026 for the subcutaneous induction. Of course, that -- it could be a range because it would involve sBLA, a prior -- potentially a priority review and other such aspects, which could shift it, but that is the -- that is what Eisai has communicated. I just wanted to reaffirm that. Thank you.

So, the outcome and not the filing?

Yes.

Obviously earlier?

Earlier.

Yes.

Thank you.

Thanks, Priya. Let's move to the next question, please.

We'll go next to Brian Abrahams with RBC Capital Markets.

Hi, there. Good morning. Thanks so much for taking my question. With regards to LEQEMBI subcu, on the FDA request for immunogenicity data, I'm curious if you have a sense as to what drove that request. Your level of confidence that the PK will be linear using half the subcu dose? And then, when are you proposing that patients in their course of treatment should transition from an IV to a subcu maintenance? Thanks.

Sure. Thanks, Brian. So overall, we -- as you know, we had tested the 720 milligrams in the naive patient population that was in the Clarity AD open-label extension sub-study for subcutaneous. Now, from that -- in addition to that, we had modeling data and this is what we are proposing for 360 milligrams to be the weekly maintenance, and the FDA is just requiring additional immunogenicity data. We see this as a reasonable request, and we are already in the process of generating it. So overall, we don't expect that the bioequivalence is going to be in question. This is now really about the immunogenicity and actually generating on patients who would be tested for this. So, that's what we expect with that. Can you remind me what was the second aspect of your question?

When are you proposing that patients transition from the IV to the subcu maintenance? Is there data supporting what -- when in the course of treatment that transition should happen?

Yes. And I think that's important because we have filed for an intravenous maintenance like -- we've already completed this filing Q1 2024, and really that has come from three lines of evidence. The Study 201, which was the Phase 2 study, the GAAP period modeling, as well as open-label extension in the Phase 3. So that's what's informed our maintenance IV filing. And really, it will be decided along with the FDA on what is the appropriate time for transition from IV biweekly to weekly now -- up to four-weekly. And in addition, following that, we'll have the subcutaneous maintenance discussion. So really, it's very systematic and we need to first get through all the IV maintenance. And in parallel, we have the SC maintenance. I hope that makes sense.

Thanks, Priya. Let's move to the next question, please.

We'll go next to Jay Olson with Oppenheimer.

Oh, hey. Thanks for providing this update. It seems like compared to previous quarters, you're focusing more on your three commercial launches and relatively less on the R&D pipeline. Is there any particular reason for that shift in focus? And how much more work do you plan to do to optimize your R&D portfolio? Thank you.

I'll start. I mean, I think we have first -- four data readouts coming in midyear. So, I think, we felt we'd have more data when we -- it makes sense to bring back the R&D when we've got more data. I would say actually from a prioritization point of view, and Priya, you can weigh-in here, but I think we've largely done the job of having projects that are either projects of conviction, or projects where we're waiting the data outcome. They're in-flight and just given the nature of neuroscience projects, we wait -- we need to wait and see what the data say. I think you're going to find us much more disciplined about whether we progress or not. Our go/no-go decisions, I think have all been clearly defined for those. I think the next job is really now to build out the pipeline, as I talked about earlier, that we want to diversify our business a little bit more than we have in the past. So, Priya is certainly working along with Jane on thinking about what things we can additionally bring into the pipeline from outside. But, Priya, I don't know whether you want to add anything there.

Thanks, Chris. I think you covered it. That's exactly right. We are very excited about our four readouts. We are preparing for them. We have already worked through go/no-go criteria. And we continue to remain very excited about the rest of the pipeline that's in mid and late-stage, particularly our anti-tau ASO BIIB080, as well as our two Phase 3 programs in SLE, litifilimab as well as dapi that we just talked about, and with litifilimab also in cutaneous lupus. So, we have a number of projects in early phase development, and we're trying to be very disciplined about making sure that we make evidence and data-based decisions.

Thanks. Thanks, Priya. Next question, please.

We'll go next to Chris Raymond with Piper Sandler.

Thanks. Just maybe a strategic question on your biz dev strategy. So, Chris, I heard your comments around diversifying away from neurology. You guys have been saying that for a while and your deals are focused on areas other than MS. But there is actually, if you look across the industry, some decent early innovation in MS. Even with your business on the decline, our checks still indicate that Biogen remains a trusted company and there's an awful lot of value, I would argue with that market presence. I guess maybe just the question here strategically is, is your activities in business development, is that due to your view of the need to diversify away from MS strategically? Or is it a view that you just haven't seen an early asset worth licensing, or is there some other underlying dynamic of the MS market that has led you guys to prioritize other areas? Thanks.

Yes, well, there's a little bit of a lot of the above in there. I think the first is, we haven't abandoned MS. We do have programs in research early. The unmet need in MS has really narrowed. It's really the progressive form, which is a very tough indication really to go after. But we have programs still in ALS. And in fact, I think the fact that QALSODY was approved has actually proven to be an enormous scientific achievement. It may not be a major financial achievement, but this really opens up the field to having a biomarker where you can tell whether something is working or not in ALS. And so, we have a number of programs in ALS. We're in Huntington's. We have a program in Parkinson's, as you know. We've got TAU, which I think between TAU and lupus, we see as programs of high conviction within the company. So, we feel that -- I think you're right. We are very well-placed. Neurology, I wouldn't just say MS, but neurology. But the reality is that, we sit there with programs that are very difficult to predict, very expensive, very long running. And when you actually look at the ability to do external deals, that field is also very narrow. There's just not that many people working in the CNS space. So we're by no means abandoning it. And in fact, the fact that we go after these really tough diseases is really a source of pride within Biogen. And I have to say, I continue to be amazed at the capability and talent we have within the organization. But the reality is, we need to have more predictable results out of R&D. And I think we do have a lot of that capability within the company. I don't see us ever -- moving -- going left turn into oncology or something like that. But I do think we have a legitimacy and being in rare diseases and expanding into immunology. And in fact, I think what we've been doing in MS and in fact lupus is really an indicator of that. So, I think we're going to continue to branch out, but it also branches out our opportunity set for collaboration, and not just diversifying our portfolio.

Thanks, Chris. And can we take our last question, please, operator?

Yes. We'll go next to Terence Flynn with Morgan Stanley.

Great. Thanks for taking the question. Maybe a two-part on LEQEMBI. Just wondering, obviously, you talked about the number of unique prescribers more than doubling this quarter. Just wondering how much more breadth you're expecting from the field force expansion here as we think about the forward through 2024? And then, any early insights on duration of treatment that you're seeing so far? Thank you.

Yes. So thank you for the question. My outlook for the rest of the year is, when you really think about the phases that these IDNs are in, and even you see these small accounts that they do move fast out in the community. And if you really take a step back and look in context for the IDNs, we got an approval -- full approval in July. It took about six to eight months for these very large systems to get organized, which is that staged and phased approach I talked about. And the fact that now they're actually opening up these other sites for diagnosing and prescribing, I believe that you're going to also see the number of physicians prescribing increasing, and it will continue to increase throughout the rest of the year. If you look at how many physicians that we are targeting and the numbers that are actually prescribing, we still have a good delta there. And so, I do see that continuing, especially with the field force coming in, if they're covering, our goal is really to drive the acceleration at these large IDNs. I talked to you about the Priority 100, but keep in mind, we actually target quite more than that. I just keep referring to the priority. And there are many other IDNs that are also prescribing and are also expanding and extending. The second part of your question was around --

Duration.

Duration. What's interesting with this and there's been a lot of conversations with many of these prescribing sites. Physicians lay very specific and explicit expectations with patients that when they go on this therapy, their expectation is they come in, every two weeks, to get their IV infusion and that they stay on product. And what we've seen thus far, and what we believe to be happening thus far is patients are staying on product. We hear that as feedback from the physicians. We also hear that as feedback from the numbers that we see the data that we see. So, so far with duration, the plan is that they're keeping patients on product. I think there are questions out there as to what to do about duration, but in the absence of any data, physicians are keeping patients on.

Right. Thanks, Alisha, and thanks to all of you for joining us today for the call and the IR team, of course, is available for follow-ups. Have a good rest of your day.

This does conclude today's conference. We thank you for your participation.