argenx Q1 2025 Earnings Call Transcript

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Operator

Good morning. My name is Rob, and I will be your conference operator today. I would like to welcome everyone to the call. At this time, 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

Thank you. I'd now like to introduce Beth Delgioco, Vice President, Corporate Communications and Investor Relations. You may now begin your conference.

Beth DelGiacco
Beth DelGiacco
VP - Corporate Communications & Investor Relations at argenx SE

Thank you. A press release was issued earlier today with our first quarter twenty twenty five financial results and business update. This can be found on our website along with the presentation for today's webcast. Before we begin on Slide two, I'd like to remind you that forward looking statements may be presented during this call. These may include statements about our future expectations, clinical development, regulatory timelines, the potential success of our product candidates, financial projections, and upcoming milestones.

Beth DelGiacco
Beth DelGiacco
VP - Corporate Communications & Investor Relations at argenx SE

Actual results may differ materially from those indicated by those statements. Argenx 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 Hauermeyer, chief executive officer Carl Gubitz, chief financial officer and Carrie Mathey, chief operating officer. I'll now turn the call over to Tim.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thank you, Beth, and welcome everyone. I'll begin on slide number three. At NGINX, we are building our company for the long run. Our strategic decision making paired with an agile approach has positioned us to deliver sustained growth in a dynamic and evolving market landscape. It's with this same long term focus that we introduced an ambitious Vision 02/1930 to reach 50,000 patients across 10 labeled indications and advanced five safety assets.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

This quarter we continue to execute against a bold innovation agenda keeping us firmly on track to realize this vision. We successfully launched the prefilled syringe in The U. S. And Germany to reach more patients with BIPGAR. We are advancing 10 registrational and 10 proof of concept studies across our pipeline and we remain on track to progress four INDs in the clinic this year with ARGX-one hundred nine and ARGX-two thirteen now in Phase one studies.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Slide four, our focus on execution continues to yield results. Let's begin with our commercial business where underlying growth is exactly where we expect it to be. Consistent with last year, first quarter results reflected typical seasonality following an exceptional fourth quarter. Karen will share more details on launch dynamics later in the call, but big picture, key position and patient metrics across both JMG and CIDP continue to be strong. Looking at the full year ahead, we remain confident in our ability to drive consistent growth.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

First, we were thrilled to receive an optimal label in The United States with the recent FDA approval of the CAR HYTULLO prefilled syringe for self injection. This comes at the perfect time to maintain our growth momentum and broaden our patient reach in gMG and CIDP. We are excited with the opportunity ahead for CIDP and have just launched our patient activation campaign. This will be critical to empower CIDP patients in their decision making to choose the best therapy for them. We continue to see a demand for innovation in the MGMTiDP market.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

We are building the broadest offering possible to support this unmet need. This includes advancing our auto injectors and progressing our late expansion studies in seronegative and ocular MG. Finally, we recognize that the global market is dynamic at the moment. While it is still too early to speculate how our industry will be impacted by future policy developments, we are confident that our strategic decisions to date have positioned argenx to navigate a range of potential outcomes. We are prepared to meet growing demand for our precision therapies with a robust global supply chain and a strategy to manufacture in each region for that region.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

This includes continued and long standing investments in our U. S. Manufacturing capabilities to ensure long term scalability. Slide five, taking a step back, the success of our commercial efforts are rooted in patient and physician demand for new and innovative treatment solutions. Last month at AAM, we had the opportunity to present data that reinforced the broader potential of this drug and reflect our commitment to generating data that is most meaningful to the neurologist community and the patients they serve.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

This drug continues to set a high bar with its sustained efficacy and improved quality of life measures for patients living with gMG and CIDP. Beginning

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

with gMG,

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

more and more neurologists are recognizing Minimum Symptom Expression or MSC as the metrics most relevant to patients. New data from the ADAPT NEXT study showed that fifty six point five percent of patients achieved MSC at any point during treatment. We believe that an individualized treatment approach is the best way to treat gMG, given that each patient experiences the disease differently. The ADEPT NEXT study supports this view, showing that both fixed and biweekly dosing regimens can deliver rapid, meaningful and sustained improvements for up to one hundred and twenty six weeks. Recognizing that we're still early in the launch of DevGuard Hytrolol in CIDP, we were encouraged by our engagement with treating physicians and some of the positive patient experiences that are already seen.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

We shared new open label data showing that HYKTULLO can drive sustained functional improvement and highlighted our switch study design, which looks at patients switching to Hexulo within one week of the left IVIG treatment. Finally, Plinabulin's strong and predictable safety profile remains a critical part of its value to patients and physicians. We have over 8,000 patient use of data across studies and are proud to have a label with no vaccinations, no ramps, no black box and no monitoring. Clipping on our Vision 2,030 will also depend on the progress of our pipeline and I'm particularly energized by the breadth of indications we are pursuing across multiple first in class assets that open the door to new disease areas with high unmet need. We continue to push the boundaries of our understanding of FcRn as we explore new therapeutic areas with efgartigimod including rheumatology with myositis and Sherman's and endocrinology with TED.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

These are high prevalent diseases where we see a clear path to deliver meaningful differentiated benefits to patients. With emfarsibrug, we have taken a bold approach, advancing our C2 inhibitors into two registrational head to head studies against IVIg in both MMN and CIDP. These trials reflect our commitment to disrupting the treatment paradigm for each of these diseases by challenging the standard of care and bringing forward innovation for patients in need of new precision treatment options. And finally, let's take a look at what's ahead for the rest of the year with several readouts across the pipeline. The seronegative gMG study will be the first of our 10 registrational trial readouts, which has the potential to expand the breadth of GNG patients we treat.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Beyond that, we have proof of concept readouts in lupus nephritis with efgartigimod, delayed graft function with empassibrobar and CMS with ARGX one one nine, the first clinical readout for our third asset. We have two primary objectives with our proof of concept study. First, to gain confidence in the signal observed to invest in further development, and second, to thoughtfully shape the phase three design. Before turning the call over to Carl, I want to circle back to our innovation mission. We have always put innovation at the forefront of our decision making, which means prioritizing what patients need and ensuring that we remain forward thinking to prepare ourselves for the long term.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

With an enviable financial position, we are able to continue investing in our innovation engine, capitalizing on both commercial and clinical opportunities to deliver sustained long term value. And with that, I will turn the call over to Karl.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Thank you, Tim. The first quarter twenty twenty five financial results are detailed in this morning's press release. Total operating income in the first quarter totaled $8.00 7,000,000 This reflects $790,000,000 in product net sales and $17,000,000 in other operating income.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

The product net sales of $790,000,000 represents 99% growth compared with a corresponding prior year quarter. The product net sales break down by region to $681,000,000 in The U. S, Dollars Thirty Two Million in Japan, Dollars Fifty Seven Million in the rest of the world and $20,000,000 of product supply to Zai Lab in China. On a quarter over quarter basis, comparing Q1 twenty twenty five with Q4 twenty twenty four, the growth is 7%, with The U. S.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Growing at 5%. We saw strong underlying demand in both gMG and CIDP with growth in net sales impacted by two factors. First, typical Q1 seasonality with reverification of benefits for patients. And second, Medicare redesign took effect on January 1, which accelerated the evolution of our channel mix to Part D. This had an impact on gross to net for the quarter.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

We expect PFS self injection to further drive a shift to Part D, though over time, the impact on revenues from increased gross to net will be offset by patient volume growth, specifically our ability to reach new patient populations with PFS for self injection. In Japan and the rest of the world, the quarter over quarter growth continues to be in the high teens. Next slide. Cost of sales is $81,000,000 in Q1. This reflects a gross margin of 90%, which is in line with previous quarters.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Total operating expenses in Q1 twenty twenty five are $668,000,000 a quarter over quarter growth of 2%. The increase is explained by a $12,000,000 increase in R and D, offset by a decrease of $10,000,000 in SG and A. This results in operating profit for Q1 of $139,000,000 The quarterly net financial income is $36,000,000 We benefit in the quarter from unrealized exchange gains of 27,000,000 on our non U. S. Denominated cash balances.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

The effective tax rate for Q1 twenty twenty five is 16%. After tax, the profit for the quarter is $169,000,000 Our cash balance represented by cash, cash equivalents and current financial assets is $3,600,000,000 at quarter end, an increase of $238,000,000 from Q4 twenty twenty four, driven primarily by cash flow from operations. Our previously issued guidance on total R and D and SG and A for the year remains unchanged. I will now hand it over to Karen.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Thank you, Karl. Slide nine. Our patient centric approach to innovation continues to deliver real world results as we have now successfully bought a first in class medicine to patients across multiple markets, executing launches across three indications, three product presentations in over 30 countries in less than four years. With this launch cadence, we have maintained steady momentum and delivered 13 quarters of growth. This is a remarkable achievement, and I'm incredibly proud of the entire Argenx team for the focus, dedication, and the collaboration that has made it possible.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

We continue to drive meaningful impact with ZivGut, expanding our reach to new patients and prescribers in both CIDP and MG as well as ITP in Japan. With the recent approval of our presale syringe, which further enhances patient access and convenience, we expect that momentum to continue. Today, I'll walk you through the dynamics behind our performance this quarter and how we're positioned to continue to drive sustained long term growth and deliver lasting outcomes for patients. Slide 10. We're continuing to deliver on our long term growth strategy with 99% year over year revenue growth for the quarter and steady growth delivered across every region and indication.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

After an incredibly strong fourth quarter, we faced typical first quarter seasonality in The US, which, similar to last year, is primarily due to benefit reverification. This quarter also marked the first industry wide impact of Medicare Part D reform, which is accelerating the evolution of our channel mix towards Part D. As Carl outlined, due to this dynamic, we saw an impact on our gross to net over the quarter. Looking beyond these technical impacts in The US, we saw a strong quarter and we continue to deliver consistent growth. I'm very pleased with our performance in new patient starts, in new prescribers, and in high patient conversion rates.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

We believe there is significant commercial opportunity ahead of us for both gMG and CMP. In gMG, this got achieved the fastest market share growth amongst branded biologics, solidifying the number one position in the MG market. VISTA Hytrolo is the key growth driver contributing to a strong quarter over quarter increase in new patient initiation. In CIDP, our strong launch momentum continues with consistent quarter over quarter growth in new patient starts. Although we recognize the CIDP market dynamics are unique from MG, early trends reinforce our confidence in the significant long term opportunity for Vivint and Hytulo in this market.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

In addition to strong patient starts in both MG and CIDP, we continue to see consistent new prescriber growth. Over the quarter, we added about two fifty first time Vivint prescribers, bringing us to over 3,700 total prescribers, and we saw a reciprocal halo effect between MG and CIDP. Reaching new prescribers is a critical priority to increase the breadth and depth of patients that we reach. We also saw a solid performance internationally. Japan CIDP launch is up to an encouraging start, echoing The US experience with patients and prescribers welcoming the first novel mechanism for CIDP treatment in thirty years.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

The contribution from the rest of the world continues to grow as we secure pricing and reimbursement agreements across Europe and Canada. In Europe, Vizgot Subcutaneous continues to expand our gMG uptake, including initial prefilled syringe use in Germany. Lastly, we're close to bringing VIZAR to its second indication in The EU with positive CHMP opinion last month in CIDP. Slide 11. The recent approval of our prefilled syringe for self injection in The US comes at the perfect time to enable our continued growth momentum in MG and CIDP.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

The label we received is an optimal outcome. Patients now have the ability to self inject in as little as twenty to thirty seconds after being trained with proper instructions, They can do so at home or in the ACT office. Patients will have the flexibility and independence to manage their treatment in a way that fits their lifestyle and continue to benefit from Zivka Hytrolo's strong efficacy and favorable safety profile. The first patients have already been dosed with PFS for self injection in The US and Germany. Reception to date has been very positive with encouraging initial patient prescriptions.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

You'll recall, we are not pursuing a conversion strategy with PFS for self injection. Rather, our goal is to reach more patients earlier in the treatment paradigm. We're seeing that play out already with fifty percent of initial enrollment first time the gut uses. Patients have been vocal in their positive feedback, often referencing the PFS as game changing. One patient commented that he was now ready to take back control of his life and eager to travel with his family.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Another patient shared her relief to be able to manage her work schedule instead of taking off significant time for weekly infusion. We're just at the beginning of this launch, and we continued market expansion in The US and future expansion opportunities in Canada, China, and Japan. Slide 12. We're transforming the MG and CIDP treatment paradigm of Zivgart and Zivgart Hytrulo, and we're empowering patients to expect more from their treatment. This is especially true for CIDP patients who have not seen new novel mechanism of action in the space for close to thirty years.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Physicians are more conservative in switching their CIDP patients between medications in general and often prefer an active request from the patient before doing so. In February, we successfully launched our patient activation campaign, which is empowering patients to ask their neurologists about ZIVGAR HITULO. We are seeing a very high grant rate to these requests, demonstrating that neurologists believe in the value proposition of ZIVGAR HITULO for CIDP. Our patient engagement efforts across both gMG and CIDP led to a significant increase in patients actively requesting Vipgar or Vipgar HYTULLO over the quarter. Slide 13.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

What excites me most is the tremendous opportunity ahead to expand the impact of our precision medicine. We are exactly where we need to be. We have the right strategy in place to reach patients earlier in their treatment journey. We successfully launched our prefilled syringe, and we're generating the data needed to position Vivgut as the treatment of choice in both MG and CIDP. And this is just the beginning.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

With multiple potential launches ahead, we're ready to expand into new high unmet need indications, bringing our therapy to thousands more patients and advancing our vision to redefine the standard of care in autoimmunity. With that, I'll turn the call back to Tim.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thank you, Karen. We have an incredibly strong foundation to deliver significant growth this year and beyond, which puts us perfectly on track to achieve our Vision 02/1930. We have the benefit of a strong financial position to continue investing in our commercial business and early innovation. With multiple expansion opportunities ahead, we plan to sustain our growth trajectory in MG and CIDP. Additionally, we have a steady cadence of several milestones across a robust pipeline which will further contribute to patient growth and support our leadership in autoimmunity.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Execution has always been a key strength of our company and therefore we enter the remainder of the year confident in our ability to deliver value to our patients and shareholders whose long term support has been critical to our success. We will now open the call for questions.

Operator

Thank you. We will now begin the question and answer session. Your first question comes from the line of Tazeen Ahmad from Bank of America. Your line is open.

Tazeen Ahmad
Tazeen Ahmad
Analyst at Bank of America

Hi guys. Thanks for taking my question. I wanted to ask a more broad one on the profile of the GNG patients at this stage of the launch that are starting with CAR therapy. So can you just tell me what portion of the curve you're on in terms of onboarding you know, the patients that are out there that are not currently receiving therapy? And then also, are you noticing any changes with discontinuation rates and any impact from competing products so far?

Tazeen Ahmad
Tazeen Ahmad
Analyst at Bank of America

Thanks.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Thanks for the question, Tazeen. Appreciate it. And and as you say, I mean, where I come from with thirteen quarters into the launch for MG, and I'm really proud of the fact that we've continued to deliver growth quarter over quarter despite off a very high quarter last in q four. And I think what that indicates is is that we're still early in the launch curve for for MG.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

What we see in terms of the patient profile, to your specific question, we still see about sixty percent of patients coming to Vivint from orals. So it shows that we're still moving into earlier lines of treatment, which is exactly the strategy that we're pursuing as we expand the market. And what we're seeing is the market for biologics is growing, and Vivint is leading that growth. We maintain the number one market share amongst biologics in MG. So we're expanding our leadership and prefilled syringe, and the launch of prefilled syringe is only gonna accelerate this as we continue in the launch.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So I would say we're at the early phase or early stages of the launch curve at this point. Thanks for the question.

Operator

Your next question comes from the line of James Gordon from JPMorgan. Your line is open. James, your line is open.

James Gordon
James Gordon
Vice President at JP Morgan

Hello. James Gordon, JPMorgan. Thanks for taking the questions. Hello. Can you hear me?

James Gordon
James Gordon
Vice President at JP Morgan

This is James here. Can you hear me?

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yes. We can hear you. Yes. We can hear you, James.

James Gordon
James Gordon
Vice President at JP Morgan

Hello. Can you hear me okay?

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yes, James. We can hear you.

James Gordon
James Gordon
Vice President at JP Morgan

Testing whether you can hear me.

Operator

We are experiencing some technical difficulties with that line. We're gonna move on to the next question from Alex from, sorry, Alex Thompson from Stifel. Your line is open.

Alex Thompson
Managing Director at Stifel Institutional

Hey. Great. Congrats on the quarter, and thanks for taking our question. I guess, you know, as we think about the PFS launch now with three, VivGuard forms in the market, can you talk about how we should think about net price, over over time? Thanks.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks. Happy happy to talk about the PFS launch. Maybe I'll just start by saying that we're really pleased with the label that we received as part of the approval, and I wanna share a huge congratulations to the team. We did get the optimal label, and what we're seeing already is positive feedback from the PFS launch from both prescribers and from patients saying that it's a game changer.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So so we think that this will be an expansion opportunity and that it will drive growth continued growth that they've got through the year. But maybe, Carl, you wanna comment on the gross to net?

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Yeah. Thank you, Alex. PFS will, of course, be pharmacy benefit, and the gross to net will have a different dynamic in grow in the pharmacy benefit versus a medical benefit due to the 20% manufacturers have to pay for patients in the catastrophic phase. Therefore, the net price per patient for PFS, the patients will be lower than for the patients in the medical benefit, which will largely be IV and by the car, by through low. At the at the moment, we will we will maintain the 225,000 for an MG patients and the 454 CIDP patient.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

But over time, that will evolve, and we can give you updates later on.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yep. Do you wanna also just answer the discontinuation question from the last Yes, Tazeen. Sorry. I think you asked about discontinuations as well. And so just to come back to that, we're not seeing any shift in discontinuation.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Fact, we see the consistent discontinuation rates. And I would say given that it's a maintenance therapy and a chronic treatment, the the it's quite strong, and you can see that the patients are are definitely appreciating staying in MSC and the adverse event profile. So so no shift in discontinuation rates for MG.

Operator

Your next question comes from the line of Vikram Prohit from Morgan Stanley. Line is open.

Vikram Purohit
Vikram Purohit
Analyst at Morgan Stanley

Hi. Great. Good morning. Thanks for taking our question. Ours is on AIDP.

Vikram Purohit
Vikram Purohit
Analyst at Morgan Stanley

If you could just help us understand in a bit more detail the cadence of new patient starts, where you ended 1Q with in terms of patients on therapy and how you might expect that to trend throughout the course of the year? Thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks for the question on the CIDP launch. I'd say we're really excited about where we are with the CIDP launch. What we've seen is continued momentum since the beginning of launch and through Q1. The execution continues to be strong.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

When you look at the underlying fundamentals to your question, what we see is continued new patient adds quarter over quarter. We also continue to see new growth quarter over quarter, which is a really important measure to demonstrate that we're that we're reaching more prescribers and therefore reaching more patients. And the other really important feedback that we have from this quarter is the consistent patient stories that we're hearing about the transformational impact that VivGuard is having on on their CIDP. So, I mean, patients are at the center of our launch and are the the a key to the CIDP launch. We launched our DTC campaign in q two, and what we're seeing is that more and more patients are initiating the request to switch with their prescribers.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

And in the majority of cases, their neurologists are granting that switch request. And and what that shows us is that neurologists believe in the profile of Vivgat for CIDP. So all of the underlying launch metric metrics for CIDP continue to be very strong.

Operator

Your next question comes from the line of Rajan Sharma from Goldman Sachs. Your line is open.

Rajan Sharma
Rajan Sharma
Executive Director at Goldman Sachs

Hi. Thanks for taking the question. Just to just follow-up on on the Q1 effects. You mentioned that there were two factors that you kind of talked to as being headwinds to revenue growth for the quarter. So that was a reverification and then the Medicare redesign impact.

Rajan Sharma
Rajan Sharma
Executive Director at Goldman Sachs

Could I just push a little bit on relative magnitude of each of those and which was the larger impact in Q1? Thank you.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Rajan, thank you for your question. Let me talk about the gross to net impact. In prior quarters, we've seen a gradual increase quarter over quarter of Part D. At the close of q four twenty twenty four, it was a it was a minority, a small portion of patients. At the last earnings call, we discussed that in 2025, we have a launch of PFS self injections, Patient patients under the pharmacy benefit, which is Medicare Part d, will grow.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

And as that mix evolve between medical and pharmacy, the gross to net will increase. What we've seen now in q one is a with a Medicare redesign is an acceleration of patients choosing to receive high trulo at home even before PFS. This underscores the need we will be filling with p s PFS self injection as it will expand the market. So the in terms of the magnitude of a gross to net, we can't get into more detail now. We will provide probably more detail at the end of q two two, but you did see an increase in gross to net.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

But the majority of the impact you're referring to is to do with the seasonality relating to the reverification of benefits. That is an industry benefit industry impact which you always see. Maybe, Karen, you wanna talk about that.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. I I thanks, Kyle. I I think that's really clear, and I think that's important to to note. What we saw in q one is similar to what we saw in q one last year and the and the normal industry dynamics of seasonality related to benefit reverification and impacting the volume. But remember, this guide is a growth story.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

We saw growth in q one. We had the PFS approval in q one, and what we expect to see is continued growth and continued cadence of growth through the the remainder of of the year as we continue to launch PFS for both MG and CLDP.

Operator

Your next question comes from the line of James Gordon from JPMorgan. Your line is open.

James Gordon
James Gordon
Vice President at JP Morgan

Hello. Thanks, James, again. Thanks for taking the questions. Bear with me for any technical issues here. The question was most favored nations has come into focus again, and there were some concerns around different list prices for Vivkart in different places.

James Gordon
James Gordon
Vice President at JP Morgan

So can you remind me how Vivkart's list price varies between The U. S, EU and Japan? And also, have you already set the PFS price outside The U. S? So how the list price varies there?

James Gordon
James Gordon
Vice President at JP Morgan

And if I

James Gordon
James Gordon
Vice President at JP Morgan

could also just ask a follow-up question. So as has been discussed, some

James Gordon
James Gordon
Vice President at JP Morgan

impact this quarter from patients shifting to Part D, and that comes then with a catastrophic discount from the company. But looking to Q2 and the rest of the year, are you seeing significant further incremental headwinds from this Part D shift and then falling net price that we need to be wary of when we're thinking about Q2 and

James Gordon
James Gordon
Vice President at JP Morgan

the rest of the year? Or is one way

James Gordon
James Gordon
Vice President at JP Morgan

of thinking about it looking at the phasing we saw last year in 2024, where Q1 was a bit softer sequentially, but then Q2 saw quite acceleration because you didn't have the recertification headwind. And then you've PFS coming in and you've got more CIDP coming in. So should we look at last year's phasing for a bit of a guide for what this year's phasing looks like?

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

Okay. Thank you, James. I think you asked three questions, so let me take them one by one. First one is on our most favored nations. We have been very disciplined and aim to keep the less price in all our markets within a narrow band.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

For example, with the launch of Bevgart in Germany, the list price was set very close to The US list price. Prices evolve, of course, over time due to foreign exchange, labor expansion and so forth. But that said, we've done a good job in keeping the less prices in all our priority markets in a narrow band. On your second question, the PFS pricing have been set for in all our priority markets. So I think that's done.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

In third question, I think, in terms of of q two, I think it goes back to what Karen has said that BFS is a is an expansion strategy which will create which will which will give us more prescribers and more patients. But, yes, gross to net will also increase quarter over quarter as the the product mix between medical and pharmacy changes.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. I and I'm just gonna add. I in terms of the rebound effect that that you mentioned, I wouldn't think about it like that. I would zoom out. And what you can see when you look quarter over quarter since the beginning of the of the launch of Vivgut, when you take a line through it, it's relatively consistent growth quarter over quarter.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So we don't look at we don't look at the the ups and downs each quarter, but rather I'd encourage you to take that line through it and look at the long term trajectory. And we're confident that that consistent growth will continue over the long term.

Operator

Your next question comes from the line of Derek Archila from Wells Fargo. Your line is open.

Derek Archila
Derek Archila
Managing Director, Biotechnology Equity Research Analyst at Wells Fargo

Hey, good morning and thanks for taking the questions. Just wanted to see given the ADAPT NEXT publication and the dataset there, are you assuming increasing number of treatment cycles in MG patients as part of your growth calculation to offset the Part D exposure? Thanks.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thanks, Derek. Thanks for the question. If you look at the material consumption between that next or cyclical dosing actually net net you end up using the same amount of materials. So we do not believe this is going to materially impact the dosing of the drug. I think what is really important about that next is that now we have taken the individualization to the end.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Now each patient can dose the drug the way it should be dosed from cyclical to continuous dosing. So now we can offer the full spectrum. We're very proud of the data at AAN. I think we showed impressive efficacy data from DATNEXT with a fifty six percent MSC, stick and span safety profile and real nice continuation over one hundred and twenty six weeks of use. Thank you for the question.

Operator

Your next question comes from the line of Jaron Werber from TD Cowen. Your line is open.

Yaron Werber
Managing Director, Senior Biotechnology Analyst at Cowen and Company

Great. Thanks so much. Maybe Karen, just a question for you on CIDP. Is there

Yaron Werber
Managing Director, Senior Biotechnology Analyst at Cowen and Company

any chance you can give

Yaron Werber
Managing Director, Senior Biotechnology Analyst at Cowen and Company

us a little bit of sense how many patients did you have during the quarter or finish during the quarter? And then sort of related to that, at AAN, there was a publication, right, that looked at safety in CIDP, and you had just over 1,300, I think it was 1,316 real world patients on on VidGuard at that point. Can you triangulate that maybe to, again, your commercial patient numbers, on CIDP? Thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thank you. Thank you for the question. We're not updating that number at this moment. What we'll do in the style of what we've done for other launches is update the number as we hit different milestones.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

But what I would say, again, just zooming out, is we have had consistent patient ads quarter over quarter and consistent prescriber growth in CIDP. We've also seen consistency in where the patients are coming from. And and what I mean by that is eighty five to ninety percent of the patients continue to be switched from IVIG or subcutaneous IG to VivGuard. And that's exactly in line with where we thought we would be at this moment in launch and with the 12,000 TAM. So we think we have a long way to go in terms of our growth.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

We're just at the start of the growth trajectory with the CIDP launch, and certainly PFS will be a strong driver of that continued expansion as we continue to launch PFS through the year. Thanks for the question.

Operator

Your next question comes from the line of Victor Flock from BNP Paribas. Your line is open.

Victor Floc'h
Equity Research - Pharmaceuticals at BNP Paribas CIB

Great. Thanks a lot for taking my question, Victor Flock from BNP Paribas. So I was just I mean, obviously, there has been a lot of focus on the pricing implication of the PFS ramp up at the party product. But at the same time, think it would be helpful if you could share with us your expectation in terms of incremental volume attached to the PFS opportunity. I mean, I think you've notably said that you were basically not following a conversion strategy.

Victor Floc'h
Equity Research - Pharmaceuticals at BNP Paribas CIB

So I mean, you are looking at to add patients. So I mean, I think we tend to look at the pain right now. We tend to look at the implication on price. But I mean, what are the your expectation in terms of volume growth tied to the PFS? Then my follow-up is very much close to the first one.

Victor Floc'h
Equity Research - Pharmaceuticals at BNP Paribas CIB

It's about the seronegative Phase three trial. I mean, a lot of I mean, investors have been pointing pretty light news flow over the for the next part of the year. I mean, there is the Phase three in surrogate fees and maybe for some of them, it's seen as given. But I mean, I would be would be nice if you could share also your views your view on the opportunity in terms of incremental volume and potentially sales there because obviously, it's not nothing to to to grow the addressable opportunity from eighty percent to one hundred percent of patients. Even though I I agree that, I mean, it's fair to say that the the risk is pretty low.

Victor Floc'h
Equity Research - Pharmaceuticals at BNP Paribas CIB

But, yeah, any comment on on volume would be would be super helpful. Thanks so much.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks for the question. I'll take the first one. I think Tim will take the second. So I would say we're confident about PFS driving significant volume growth both for MG and CIDP.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

I I would say we got the optimal label, and I would like to say a huge congratulations to the team. I mean, when you look at twenty to thirty second injection time, no specific monitoring or training requirements, these are all features. But the benefit that we see and that we hear from patients are that they are completely free from the office. We hear that they're excited. You heard in the script that patients are describing this as a game changer in terms of managing their MG and CIDP.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So as you said, this is a market expansion opportunity for us. What we're seeing in the early data is that 50% of the PFS prescription new to Vivgart patients. So they're not converted, rather they're overall new to Vivgart, and that's exactly in line with this market expansion strategy. So if you zoom out, what we're looking to do in both MG and CIDP is bring new innovation and patri patient centric innovation to the market, and we're seeing this exactly in PFS. And and that's what's gonna drive the long term growth trajectory for both of those indications.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

And then maybe for the seronegative and the news flow, Tim, do you want to take that?

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yeah. I think Victor, you're right calling out the the news flow for this year, which I think is strong with one phase three readout and three phase two readouts. This company is in a strong position from a news flow point of view. So the Phase three readout in seronegative myasthenia, the Phase two in lupus nephritis for efgartigimod, the Phase two in delayed graft function for EMPA and then the Phase two proof of concept in CMS-four 119. Specifically on seronegative MG, I think we are very excited about the opportunity in front of us.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

You have to think about fifteen percent of the overall MG patient population, which falls in the seronegative basket. We do know from Japan that we have seronegatives on label that DevGaP is offering the same benefit risk profile to seronegative patients as it does to the acetylcholine receptor antibody patients. So very strong performance. Now it's all about the design of the experiments. We have been learning and triangulating with the FDA on the endpoint for this clinical trial.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

We think it's a solid clinical trial and we feel very strong about the opportunity in front of us. Let me end by calling out our excitement about ocular MG, which I think is equally in size and unmet medical needs. So opportunity would be equal in ocular MG as in serum negative MG. Thank you for the question.

Operator

Your next question comes from the line of Tom Smith from Leerink Partners. Your line is open.

Analyst

Hi. This is Natsuran Suk on for Tom Smith. Thank you for taking the question. So following the approval of Prefus syringe, what's your expectation on the split among users of the three product presentations of VipGuard, IV VipGuard, Sacave Hetrolol, and Prefuso ranging MGN CDP? And similarly, how do you expect the payer mix to evolve following the oh, thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks thanks for the question. So what we're seeing already with the launch of Hytrulo is that the majority of growth in patients in new patients for MG and CIDP is coming from Hytrulo. That was even with the butterfly execution, and we expect that that will continue and even accelerate with prefilled syringe. Again, we're hearing from the market that people are really excited and that that it's a really is a game changer having prefilled syringe for self injection available for patients.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So we think that will be a growing portion of of the market. Carl, did you wanna take the question around the payer mix? I mean, I know we've shared in the past that it's fifty fifty commercial Medicare, and I don't think we expect that to change significantly.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yeah. No. I mean, I think that is what it is today. Not expecting changes. We'll keep you updated if it does.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thank you. Thank you.

Operator

Your next question comes from the line of Akash Tewari from Jefferies. Your line is open.

Amy Li
Amy Li
SVP Equity Research at Jefferies

Hey. This is Amy on for Kas. Thanks so much for taking our question. So one, is your fill finish in better considered substantially transformative? And if needed, how quickly could you move that into The U.

Amy Li
Amy Li
SVP Equity Research at Jefferies

S? And then just a theoretical question on MFN. What mitigation measures could you potentially employ? Could you price your PFS differently ex U. S?

Amy Li
Amy Li
SVP Equity Research at Jefferies

It's different product code. And would you consider pulling some of the other formulations? Thanks so much.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thanks, Simi for these two questions. The first one in terms of substantial transformation, I would use the drug substance manufacturing as your guide here. And the drug substance manufacturing of course is taking place on U. S. Territory.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Secondly, Karl already explained that I think we're in a strong position from an MFN point of view because we have shown the discipline in the way we have been maintaining setting and maintaining price in a narrow band globally in our key markets. So let's stay away from speculation, but I think we have strong cards to navigate whatever the future will bring us on these two fronts. Thank you.

Operator

Your next question comes from the line of Charles Pittman King from Barclays. Your line is open.

Charles Pitman-King
Charles Pitman-King
VP of European Pharmaceuticals Equity Research at Barclays

Hi, guys. Thanks so much for taking my questions. Just a question on kind of Part B, Part D movements.

Charles Pitman-King
Charles Pitman-King
VP of European Pharmaceuticals Equity Research at Barclays

If you could just give us a

Charles Pitman-King
Charles Pitman-King
VP of European Pharmaceuticals Equity Research at Barclays

little bit more insight on what the actual price differential is between a Part B and Part D patient over 1Q, I think that would be very helpful. And then just on kind of following on from that, thinking about the kind of future split of patients, I mean, I think you kind of highlighted PFS is expected to become an increasing proportion going forward. But given you've already been seeing these Part B patients move to Part D given the $2,000 copay related to the redesign. Like how do you expect IV to grow from here? Or should we expect like what's the future split of

Charles Pitman-King
Charles Pitman-King
VP of European Pharmaceuticals Equity Research at Barclays

the three indications or three

Charles Pitman-King
Charles Pitman-King
VP of European Pharmaceuticals Equity Research at Barclays

administrations? Thank

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

you. you. I mean, at a high level, the difference between the net price for a Part b and a Part d would be the 20% incremental rebate to which we have to pay under Part d for Delta to CMS for patients who aren't catastrophic. So that's at a high level of the difference between the two. In terms of presentations going forward, remember, we we said that in The US, we think IV will always continue to be important for The US market.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Think of a viable customers, physician preference, and so forth. But over time, from where we are today, and today, we already have a minority, but we already have part d for delta patients. Over time, that mix will increase, and you're going to see a greater proportion of patients in D for delta. Thank you for the question, Charles.

Operator

Your next question comes from the line of Myles Minter from William Blair. Your line is open.

Myles Minter
Research Analyst - Healthcare at William Blair

Hi, thanks for taking the question. Just on Vipgar, Patrolo use in CIDP, I think you mentioned eighty five percent to ninety percent of those patients were switch patients. Can you just comment on the incidence of CIDP disease worsening when you make that switch? Just wondering if you have any real world data. I think someone's presented at AAN.

Myles Minter
Research Analyst - Healthcare at William Blair

Thanks very much.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yeah. Thanks, Miles, for the question. So and I referred to the great conversation we had with doctor Karam in the panel conversation during AAN. The first thing you need to know in CIDP is that whatever switch you consider to do, be it from steroids to immunoglobulins or vice versa of the gift cards, there's always an expectation and a possibility that the patient will relapse. So this is a fact.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

You also see that in the IVIg, subcu IG switch studies. I think the symptom worsening which we have seen in the context of the AGI trial is perfectly in line with those historical studies. And in the real world actually it's a relatively small phenomenon. We see a low single digit reporting on CIDP worsening. So the vast majority of our physicians are doing it the right way.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

It seems like switching, to Vivgart one week after the last dose of IVIg is a recipe for success. But we're trying to document that in our Phase four switch study where we really try to collect evidence on how to switch best. So it is a known phenomenon in CIDP and it looks like we're navigating that quite well. Thanks for the question.

Operator

Your next question comes from the line of Suzanne Van Voorhusen from Kempen. Your line is open.

Suzanne van Voorthuizen
Head of Life Sciences Equity Research at Van Lanschot Kempen

Hi, Dean. This is Suzanne from Kempen. Thanks for taking my question. Could you please elaborate a bit more on how you look at Empah relative to Fiskars in CADP? Given the pivotal trial for Empah is different than what you did for Fiskars, can you share how you're thinking about the positioning of each product and comment how the commercial opportunity looks like for each molecule in this indication perhaps relative to each other?

Suzanne van Voorthuizen
Head of Life Sciences Equity Research at Van Lanschot Kempen

Thank you.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Thanks, Susan. Thanks for being with us and thanks for the great question. So CIDP is a heterogeneous disease. I think the ADHERE trial, which was the biggest and the highest quality trial ever done in the CIDP space is clearly demonstrating that pathogenic IgGs drive disease at least in about seventy percent, seventy five percent of the patients. The question is then why do the other patients not respond?

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

There is a suspicion that complement is in play through pathogenic IgM antibodies and we have pretty strong translational data in hand for MPA in CIDP. Now we do not want to niche MPA into kind of refractory setting only. We really want to give this great molecule the fullest chance of success in the CIDP setting. So that's why we have designed the clinical trial you all see and let the data speak. I think this is a significant market, a significant opportunity, which can harbor multiple innovative molecules to optimally address the patient needs.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

So let the data speak now. Thank you for the question.

Operator

Your next question comes from the line of Yatin Suneja from Guggenheim. Your line is open.

Yatin Suneja
Senior Managing Director, Biotechnology Analyst at Guggenheim Partners

Hey guys, thank you for taking my question. Question is on the gMG side. Could you just talk about the relative penetration in the targeted patient population you have achieved? Also, think in the past, you have said that at least in my senior gravis, you are consistently seeing 40,000,000 to $50,000,000 worth of quarter over quarter growth. Is that the same is that what you are seeing now?

Yatin Suneja
Senior Managing Director, Biotechnology Analyst at Guggenheim Partners

And how should we think about the growth just purely in G and G? And any impact of competition whether it's the CD19 or anything else that you might be seeing or complement?

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yes. Thanks for the question. On always appreciate being able to talk about MG growth thirteen quarters into launch and the fact that we're still delivering that consistent cadence of quarter over quarter growth. And and to your question, I would say it is we are seeing consistent penetration into the earlier line. I mentioned that before.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

More than sixty percent of our patients are coming from earlier lines, and what we're seeing as part of that is that the bottom the share of the market treated by biologics is growing substantially, and this guy is leading that growth. We have the number one market share. We're growing that number one market share in all of our major market. Feel I would say at the early stages in terms of penetration, we updated the TAM to 60,000. You'll recall last year.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

And with that, I think you can see that we're on the in the early stages of the growth curve for MG even though we're thirteen quarters into the launch. And what we can what you can expect and what we expect is consistent and continued growth in in whether you look at new patient starts at prescriber growth or the metric that you mentioned, which is revenue growth when you take a line through it since launch, I think we've been delivering that consistent growth on average since launch and we expect that to continue. Tim, did you have something to add?

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yes, Sarah. And you can clearly see that we have broken out of the three factory patient population, right? What it takes to really move first line and lead in the first line is the clean safety profile, which we have demonstrated for the drug. Remember what we said in the prepared remarks, no black box, no need for vaccination, no labs, no monitoring. That's a very powerful profile, you know, to go frontline as a biological.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

And what we see right Karen is that about sixty percent of the new patients coming on drug comes straight from the orals. And that is where the growth opportunity is in front of us and we think PFS will continue to fuel that.

Operator

Your next question comes from the line of Andy Chen from Wolfe Research.

Andy Chen
Director, Senior Equity Research Analyst at Wolfe Research

So, Carl, I understand that you talked about a narrow band. Just wondering if that narrow band is is less than the 20% discount that you will have to pay on Part D, is it more than the 20%? Just curious if if there's a way for you to push your patients to the Part d to minimize exposure just because Part d price cut is less likely than a Part b price cut if most favored nation comes to play comes to play? Thank you.

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

I mean, Andy, I think I don't wanna talk about percentages, but I think the reference to most favorite nations here on list prices, and I think in list prices, we are in the narrow price band. And I think we shouldn't we don't want to speculate on where below and it's still in concept phase. So what think so for now, I think I'll stop there. But maybe, Tim, you wanna add something?

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yeah.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

We're not in the business of pushing patients in into certain directions. I think what we're trying to offer is the broadest product offering possible to satisfy the needs of the different patient segments. So I think what you guys are seeing in Q1 is a very strong appetite of patients to move into self administration at home or product administration at home. That's where this acceleration under Medicare Part D is coming. But guys this is the force you need in order to spectacularly grow your market.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

So following the patient demand, satisfying the demand is the best way for growth going forward. And I think you basically see a signal here that patients are eagerly awaiting the PFS.

Operator

Your next question comes from the line of David Nierengarten from Wedbush Securities. Your line is open.

David Nierengarten
Managing Director - Equity Research at Wedbush Securities

Hey, thanks for squeezing me in. I have one question, which is, are the dynamics as you see patients getting treated with ocular MG currently, are those dynamics different from generalized MG and how that might affect your commercialization plans and duration of treatment things like that in that potential expansion? Thanks.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yes, Dave. And we don't want to squeeze you, right? I mean, your question is valuable to us. So ocular MG, higher medical needs, which we overlooked in the beginning when we were approaching the MG market. It's very debilitating, to have ocular MG.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

There's no ability to work on the screen, drive a car. There's a big social stigma associated with the symptoms, etcetera. So the truth is that today, the toolbox to treat these patients is even more limited. You would typically see that these patients are being treated with Mastinon and a high dose of corticosteroids. We know what the detrimental effects are of high dose corticosteroids used chronically.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

And we're really on a campaign of steroid tapering. We have strategic alliance with Steritas. We think the moment is right to actually offer these patients a real alternative with the benefit risk profile of that card. High unmet need, very limited treatment toolbox and an opportunity to disrupt that treatment paradigm. Thank you for the question.

Operator

Your next question comes from the line of Gavin Clark Gardner from Evercore ISI. Your line is open.

Gavin Clark-Gartner
Director - Biotechnology Equity Research at Evercore ISI

Hey guys. Apologies, but it's one more net price question. For the prefilled syringe, what are your current assumptions for the number of payer contracts that will include VBAs moving forward? Specifically wondering on the CIDP side wondering if this could offset the the gross to net a little bit. Thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. So maybe just to start before I hand over to Carl, to take a step back and remind everyone that our strategy with Vivint is to provide as broader access as possible to patients, and certainly that we don't want them to be choosing between product presentation based on price. We want them to have access and be able to choose the product presentation that fits into their life. So that's the strategy that we're pursuing. And and and what we've seen, whether it's with the MG launch, the CIDP launch, and what we expect with the PFS launch, is that our market access team, our experts are getting really good access in place quickly for patients.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

And we expect that will be the same, and the agreements will be signed quickly to get that access in place for prefilled syringe. But, Carl, did you have anything else to add on the details?

Karl Gubitz
Karl Gubitz
Chief Financial Officer at argenx SE

I mean, Kevin, I think the only thing I will say is that, generally, VBAs are less important in the pharmacy channel than the medical channel. So I think we'll leave it at that, and let's negotiate the contracts during the next few weeks. And

Operator

Your next question comes from the line of Samantha Simenko from Citi. Your line is open.

Samantha Semenkow
Samantha Semenkow
Vice President at Citi

Hi. Good morning. Thanks very much for taking the question. Another one on CIDP. I'm wondering how has the discontinuation rate in CIDP trended?

Samantha Semenkow
Samantha Semenkow
Vice President at Citi

Are you still seeing physicians giving the majority of patients a twelve week trial? Or has that trended down as they gain more experience with the GARDAN's population? Thanks very much.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks for the question. So in terms of CIDP, we are still seeing the the doctors are giving that twelve week trial. And what we've seen as the launch has matured is that there has been a little bit of an uptick in discontinuation more towards what you'd expect based on the ADHERE trial, but there is still a significant gap. And I would say we're we're below that discontinuation rate.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

So what we're seeing is patients starting on Vivint, having a positive experience, and staying on Vivint.

Operator

Your next question comes from the line of Leland Gershell from Oppenheimer. Your line is open.

Leland Gershell
MD & Senior Biotechnology Analyst at Oppenheimer & Co. Inc.

Great. Thanks for taking the questions. Just two from us if we can. Just with respect to the upcoming data from the switch study from IGA G. Vizgard in CIDP.

Leland Gershell
MD & Senior Biotechnology Analyst at Oppenheimer & Co. Inc.

Just given the dynamics there and the positive launch, just wondering how critical you see those data for physicians to effect a switch in their patients? And then also I wanted to ask with respect to 119 later this year we'll see the POC data in CMS. There are a few clinical endpoints being looked at. Just wondering if you have any threshold in mind when you look at those data for taking that program forward in CMS? Thank you.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Yep. Thank you for the two questions. So the significance of the IVIG switch study is very simple. I think the ADHEAVE trial was a very ambitious trial, but there's only so much you can answer in one clinical trial. So we addressed that this is an IG driven disease.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

We addressed the magnitude of the effects you can show across the board in CIDP patients, but we did not really study in detail the switch dynamic. Remember patients had to worsen, so they could demonstrate active disease before they came on trial. That is a bit of an artificial experimental setting. The Phase four trial is now investigating a practical question. How do you really switch an IVIg or SCIG patients to Vivcart?

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

It's simple trial design. It's a Phase four and it's meant to give some practical handle to treating physicians on how to do the switch. So I think it's an important data point. With regards to 119, a molecule which is very close to my heart, congenital myasthenic syndrome, what we learned about these patients in the natural history study is that they actually look very much like the autoimmune myasthenic patients. There is a very strong fatigability aspect to that disease.

Tim Van Hauwermeiren
Tim Van Hauwermeiren
Co-Founder & CEO at argenx SE

Limb girdle is really affected, so weakness of the shoulders, weakness of the hips. And therefore, we're really testing a menu of endpoints, It's testing which ones are really truly capturing the nature of the disease. The classical ADL and QMQ and QMG measures are in there and we know what the clinical thresholds are for clinical relevance. So we will be looking to that lens at our patients and we will inform you of course when we have the data in hand. Thank you for the question.

Operator

Your next question comes from the line of Joel Beatty from Baird. Your line is open.

Joel Beatty
Senior Research Analyst at Baird

Good morning. Thanks for taking our question. Just kind of a longer term one. I know the PFS rollout is just taking place, but have you started turning your attention a little bit now to firming up timelines and strategy regarding the auto injector? Thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks for the question. I appreciate zooming out and looking over the long term. And and, yes, our team is consistently working on the the not just the auto injector, but how we can innovate for patients overall. In terms of the auto injector, we continue with that development plan.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

The latest update we have provided is that we're moving it into being able to understand how to produce it at larger capacity. So everything is on track, and we look forward to being able to bring continued innovation to patients in the future.

Operator

And your last question today comes from the line of Sian Dang from UBS. Your line is open.

Xian Deng
Xian Deng
Director - Equity Research at UBS Group

Hi. Thank you so much for taking my question. So really, thank you for the comment on Europe European and US have very similar list price. But just wondering, could you give us some color on the the the sort of difference in terms of the net price, please? I'm sort of asking in relationship to how should we think about the commercial opportunity for PFS in Europe?

Xian Deng
Xian Deng
Director - Equity Research at UBS Group

Because on one hand, Europe does have this sort of lack of IV infrastructure compared to The US, but then on the other hand, probably, you know, we have probably less net price. So how should we think about that, please? Thank you.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

Yeah. Thanks for the question.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

And and maybe to start with, I'll reinforce something that Carl had said. In terms of our ex US expansion, we've taken a very disciplined approach to ensure financial sustainability as we provide access to patients around the world with this gut. So I think we're very well positioned in terms of our net price in from that perspective. And you're exactly right. We see the PFS opportunity as a big opportunity ex US because of the the hospital dynamics that you that you mentioned.

Karen Massey
Karen Massey
Chief Operating Officer at argenx SE

We've already seen the first patient dosed in Germany. We what we saw with the HITRULO butterfly execution is a very fast conversion in in Europe, in particular, of patients from IV to the butterfly execution of HITRULO. And we think that will accelerate with PFS, and it will certainly help to accelerate and continue our growth in rest of world or outside of The US in in the future. So we're really excited about the opportunity for PFS, not just in US, but around the around the globe with launches coming. Thanks for the question.

Operator

And this concludes today's conference call. Thank you for your participation. You may now disconnect.

Executives
    • Beth DelGiacco
      Beth DelGiacco
      VP - Corporate Communications & Investor Relations
    • Tim Van Hauwermeiren
      Tim Van Hauwermeiren
      Co-Founder & CEO
    • Karl Gubitz
      Karl Gubitz
      Chief Financial Officer
    • Karen Massey
      Karen Massey
      Chief Operating Officer
Analysts

Key Takeaways

  • Argenx reaffirmed its long-term “Vision 02/30” to treat 50,000 patients across 10 labeled indications, advancing 10 registrational and 10 proof-of-concept studies and progressing four new INDs, including ARGX-109 and ARGX-213 now in Phase 1.
  • First-quarter product net sales reached $790 million (99% year-over-year growth) with a 90% gross margin; seasonality and an accelerated shift to Medicare Part D weighed on gross-to-net, but management remains confident in consistent full-year growth.
  • The FDA approval and U.S./German launches of the prefilled syringe for Vyvgart® Hytrulo deliver a 20–30-second at-home injection option, with early data showing 50% of PFS prescriptions are new to therapy and highly positive patient feedback.
  • CIDP launch momentum continues with 250 new prescribers added (3,700 total), an 85–90% IVIG-to-Vyvgart switch rate, and a patient activation campaign driving high request grant rates and sustained functional improvements.
  • Key pipeline readouts are expected later this year, led by the Phase 3 seronegative gMG trial, plus proof-of-concept data in lupus nephritis, delayed graft function and congenital myasthenic syndrome (ARGX-119), while efgartigimod and C2 inhibitor programs expand into new autoimmune areas.
AI Generated. May Contain Errors.
Earnings Conference Call
argenx Q1 2025
00:00 / 00:00

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