Thank you, operator. Good morning, everyone, and welcome to the Kiniksa Pharmaceuticals Third Quarter 2026 Earnings Call. A press release highlighting our financial results and recent portfolio execution can be found on our website under the Investors section. As for the agenda, our Chief Executive Officer, Sanj K. Patel, will start with an introduction. From there, Ross Moat, our Chief Operating Officer, will provide an update on ARCALYST commercial execution.

After that, Mark Ragosa, our Chief Financial Officer, will review our third quarter 2026 financial results. Finally, Sanj will return at the end of the call to share closing remarks and kick off the Q&A session, for which John Paolini, Kiniksa's Chief Medical Officer, will also be on the line. Before getting started, please note that we will be making forward-looking statements today that are subject to risks and uncertainties that may cause actual results to differ materially from such statements.

A review of these statements and risk factors can be found on this slide, as well as under the caption Risk Factors contained in our SEC filings. These statements speak only as of the date of this presentation, and we undertake no obligation to update such statements except as required by law. With that, I'll turn it over to Sanj.

Thanks, Jonathan, and good morning or good afternoon, everyone. Over the last 10, 11 years, we've built this company through multiple stages of growth, and today, I'm as excited as ever about what the team and I can accomplish together in the years ahead. Kiniksa continues to build a leading IL-1 alpha and beta inhibition franchise driven by the commercialization of ARCALYST in recurrent pericarditis, as well as our progress with KPL-387 and KPL-1161.

This morning, we announced via a press release that we've raised our full-year revenue guidance to between $1.045 billion and $1.050 billion. We continue to see robust growth with ARCALYST in recurrent pericarditis, driven by strong execution and strategic investments across the business. On the clinical side, we're excited about the progress of KPL-387 and KPL-1161. The pivotal phase III study with KPL-387 continues to enroll and dose patients.

We announced today that we expect data from this trial in the second half of 2027. The team and I are really looking forward to potentially launching this drug in the 2028, 2029 timeframe. In addition to providing an important treatment option for patients with recurrent pericarditis, we believe KPL-387 could help grow the market by enabling a once-monthly subQ dosing. We are also on track to have KPL-1161, our quarterly IL-1 alpha and beta inhibitor, in a phase I clinical trial by the end of this year.

Importantly, Kiniksa's robust financial profile allows us to continue to invest in penetrating the recurrent pericarditis market and growing the IL-1 alpha and beta inhibition franchise whilst also pursuing additional value-creating opportunities. In the third quarter, we saw a continuation of strong ARCALYST momentum with Q3 revenue of $286 million. The penetration rate into the annual population of 14,000 multiple recurrence patients increased to 23% as of the end of Q3.

As shown by the increased breadth and depth of prescribing over time, adoption of IL-1 alpha and beta inhibition continues to expand among the approximately 40,000 recurrent pericarditis patients each year. The underlying fundamentals that propelled our commercial success remain strong. Since launch, we have observed robust payer approval, strong patient compliance, and greater appreciation of the need to treat throughout the multi-year duration of the disease.

Underpinning this growth is strong execution by our commercial organization and data-driven investments in ARCALYST. Our AI-supported patient identification initiatives and targeted direct consumer campaign, Heart's Home, have positively contributed to growing patient and physician awareness of recurrent pericarditis and the important role of IL-1 alpha and beta inhibition in controlling this debilitating disease. As you have heard, we now expect ARCALYST to achieve over $1 billion in revenue in 2026 and we look forward to continuing to bring this blockbuster drug to more patients suffering from this debilitating disease.

In order to grow the recurrent pericarditis market over the next several years, we plan to drive greater adoption in both the 14,000 multiple recurrence patients annually and the additional 26,000 patients annually that are experiencing their first recurrence. Kiniksa is executing against its strategy to help more patients drive more ARCALYST growth and advance KPL-387 and KPL-1161. This trajectory will help put the company on a path to having multiple commercial products, continued strong and profitable growth, and the flexibility to invest in future value creation. I can tell you that the team and I will not rest until we have helped many, many more patients. Now our President and COO, Ross Moat.

Thank you, Sanj. As you have heard, we are pleased with the continued strength of our commercial performance with ARCALYST, and we are even more excited by the substantial growth opportunity ahead. We continue to be highly focused on further increasing the penetration rate into the many thousands of recurrent pericarditis patients and continuing to evolve the treatment paradigm towards interleukin-1 alpha and beta inhibition.

As illustrated on the left side of this slide, physicians continue to report an increasing consideration of ARCALYST earlier in the disease course, including at the first recurrence. Additionally, we also see a growing appreciation for ARCALYST to be utilized earlier in the line of therapy, meaning after NSAIDs and colchicine, and importantly, prior to corticosteroids, as ratified in the 2025 American College of Cardiology Concise Clinical Guidance for Recurrent Pericarditis. In fact, approximately 50% of physicians surveyed now support this treatment approach, representing a doubling from levels over the last three years prior to the publication of this independent guidance.

As we continue to build and lead this market, our team are laser-focused on value-driven investments that aim to increase market penetration and help many more patients. Increasing education and awareness on recurrent pericarditis, ARCALYST, and the new treatment paradigm remain critical components of our strategy, and we've enhanced our capabilities through the use of AI and machine learning to reach a larger audience. On the healthcare professional side, we've done this through improving our data sources to inform us not only which healthcare professionals we should be seeing, but importantly, when we should be seeing them.

On the patient side, we've seen encouraging early indicators from our Heart's Home direct-to-consumer campaign. Based on this initial traction, we plan to expand the campaign with additional content and outreach initiatives aimed at empowering more patients to engage with their healthcare professionals about ARCALYST. As a reminder, Heart's Home is a highly targeted DTC campaign where we've innovated from traditional DTC by using AI to produce and deliver a campaign that's effective for a rare disease audience.

This campaign is aimed at educating an enriched population of likely recurrent pericarditis patients who are currently not taking ARCALYST and empowering them to discuss ARCALYST with their healthcare provider. As an early indicator of the impact of this campaign, we've seen a twelvefold increase in the traffic to our ARCALYST website compared to baseline levels prior to the campaign. Additionally, there's been an eightfold increase with engaged sessions, meaning visits where the individual spends meaningful time on the website or interacts with the content.

More importantly, approximately 55% of patients who saw the ad strongly agreed that they are motivated to speak with their healthcare provider about ARCALYST. All of these indicators are strong signals that our digital strategy is reaching the right audience and is empowering action. As this disease has a very high annual incident rate of patients coming into the labeled indication, this DTC initiative is nicely supplementing our robust execution in the field and helps us to address the substantial opportunity that we have ahead to help many more patients.

As previously mentioned, our interleukin-1 alpha and beta inhibition franchise is growing, is profitable, and has significant opportunity in the months and years ahead. With that, I'll turn the call over to Mark to review our financial results.

Thanks, Ross. Our third quarter delivered continued ARCALYST sales growth, advancement of KPL-387 and KPL-1161 development, and a solid financial position. This morning, I'll review our financial results and key performance drivers. Detailed financial information is available in today's press release. Starting with the income statement, ARCALYST revenue grew 58% year-over-year to $286 million in the third quarter, driven by continued gains in patient and physician adoption.

Operating expenses increased year-over-year, driven by higher ARCALYST revenue, which resulted in additional cost of goods sold and collaboration expenses, advancement of KPL-387 development, which drove additional R&D investment, and support of ARCALYST commercialization to reach more patients, which led to additional SG&A investment. Operating income rose to $54.2 million and net income to $47.3 million, both up significantly year-over-year. Turning to the calculation of ARCALYST collaboration profit, which drives total collaboration expenses on our income statement.

ARCALYST collaboration profit increased 67% year-over-year to $211.6 million, outpacing sales growth and reflecting disciplined commercial investment. Next, we ended the third quarter with $568.8 million in cash, reflecting approximately $43 million in net cash generation during the quarter. Looking ahead, in addition to our updated 2026 ARCALYST sales guidance of $1.045 billion-$1.050 billion, we are providing full year R&D and SG&A expense guidance.

We expect full year R&D expenses of $160 million-$170 million in 2026. This range includes continued development of KPL-387 and KPL-1161, as well as significant fourth quarter KPL-387 pre-commercial manufacturing costs. We expect full year SG&A expenses of $270 million-$280 million in 2026. This range supports continued ARCALYST commercialization, including additional personnel and promotional activities in the fourth quarter to further build disease awareness and enhance patient and physician targeting.

In closing, our third quarter results show the strength of our operating plan, a growing and profitable ARCALYST business funding the advancement of key development assets and positioning us to create value in the near and long term. With that, I'll turn the call back to Sanj for closing remarks.

Thanks, Mark. As you've heard, Kiniksa is jolly well positioned to build significant future value as we grow our IL-1 alpha and beta inhibition franchise. The team and I are on it and focused on helping as many patients as possible with ARCALYST and to advancing the development of our clinical portfolio in order to bring additional therapies to patients. With that, I'll turn it back to the operator for questions. Thank you.

Thanks, Anupam. I think I'll have John Paolini answer that. Suffice to say that our execution, across not just commercial but also the clinical development organization, as I've said before, we are enrolling and dosing patients. It's a global clinical study with global sites, and both myself, John, and Ross take pride in meeting with investigators and just getting them excited about the future. There's been some massive momentum, both internally and with our investigators. As with everything, we go at things with full force, and that's why the guidance is as well and is having results in the second half of next year. John?

Yeah, I think that's excellent guidance from Sanj. The only thing that I would add is that on clinicaltrials.gov, you can see the extent of the global nature of our program. The sites that are involved in the program across the world are all listed there. You can see the scope of effort. As Sanj mentioned, we are on the ground and engaging with clinicians, and we can feel the excitement about the program, and so we continue forward.

I'll also say we have a crack clinical operations team, and having run clinical operations for many years at Genzyme before I ran commercial, I've got a very high bar for clinical research and clinical operations. And after many, many years, I feel like we've really got the best team to do the job.

Thanks, Edward. This is Ross. Thanks very much for your comments. We are pleased to announce that we were around 23% at the end of the quarter in terms of penetration into the multiple recurrence group, which is the patients that have suffered for two or more recurrences, and that is without allocating anything to the first recurrence group, which we have about 20% of our prescriptions in the first recurrence group also.

The opportunity is very significant. While on one hand, we are happy with the 23%, and that is obviously showing a couple of percent growth versus the end of Q2 number when we shared it the time before that. The last time we shared the penetration number, I think it was at the end of Q4, which was 18% at the end of last year. That has been growing relatively nicely, but I think more importantly is the opportunity that is ahead.

Clearly there are a lot of patients in the two-plus recurrence group that we have still got to help. As I said, not allocating for even those who are in the first recurrence. As we shared from some of the market research today, the propensity and the desire for physicians to look and treat patients with IL-1 alpha beta inhibition in the first group has also been growing quite substantially over time. We think the future is very bright from that perspective.

In terms of different patient groups, aside from the recurrence number, there is really not much else to report. We are not seeing significant change necessary in the demographics of the patients or severity levels or anything else. It is just that this is a rare flaring cardiovascular disease. There are a lot of patients out there relative to a rare disease. We are trying to get out and reach as many patients as possible.

We know that they are widely dispersed around the country, and that takes a certain effort, as you have alluded to, from our sales and marketing spend and so on. Our efforts are ultimately on value-driven investments that can make sure we reach those physicians and switch more and more of them on to this new way of treating and ultimately get greater penetration into this opportunity to ultimately help more patients.

Yeah. No, Edward, maybe just to add the final part as well is that the DTC spend and field team spend that we have, and we've announced in our guidance looking forward as well, is ultimately very efficient. We are very focused on this as a rare disease market. For the DTC side of things, this is not broad-spectrum, massive spend DTC. It's very efficient, very targeted type of expenditure to address appropriately the market that we have.

Thank you, Paul. Appreciate your questions. This is John. With regard to the KPL-387 transition to monotherapy dosing and administration study, this study is designed primarily as what we call a posology study. It covers dosing administration specifically for informing the label. It's designed, as you can see in the slides, we're looking at how patients are coming from stable therapies, whether they're oral or biologic, and then transitioning to KPL-387 monotherapy at the 300 mg subcutaneous monthly dose level.

That's really what that study is designed to do. It follows very similarly the precedent of what's in the ARCALYST label, which similarly describes the transitions from NSAIDs, colchicine, corticosteroids, and anakinra. This is just really following in that tradition. That's how the study is designed and the data that will be generated. I'll turn it over to Ross to talk about ultimately other elements of transition.

Yeah. Thanks very much, John. I guess just to say that obviously we're very excited about the potential for KPL-387. Everything's data dependent as we move forward. When we tested the target product profile for KPL-387, both with healthcare professionals and patients, we were really very encouraged by the feedback that we had back. While we believe that ARCALYST has a lot of growth left in it to address the recurrent pericarditis opportunity, with KPL-387, patients did tell us that around 75% of them would prefer the KPL-387 target profile being a monthly liquid formulation, potentially auto injector over current commercial or other investigational therapies.

They also reported a propensity for a greater number of patients to start on therapy with that target product profile, as well as staying on therapy longer. When you looked at the healthcare professional side, 92% of healthcare professionals indicated a high likelihood to prescribe KPL-387 with that target product profile over available commercial or other investigational therapies. That I think reads quite positively about the future, but ultimately we are focused on conducting the clinical research and awaiting the data.

With regard to your question about KPL-1161, we are very excited about this program, which has the potential for once quarterly dosing, again, targeting the IL-1 alpha and beta signaling by targeting the receptor. This program we expect to begin a phase I program by the end of the year. To that extent, we have not yet announced or disclosed our plans with regard to development indications. Suffice it to say, though, that with that longer duration of action, that really unlocks a lot of potential for disease states, especially those that are chronic or lifelong in nature by virtue of the once quarterly dosing. Ross, anything to add?

No. That is great, John. Thank you.

Yeah, Peter, thanks very much for the questions. We do not share some of that data directly externally, but of course it is the type of thing that we look at a lot internally in the business. What we have shared is in the Q3, clearly we have seen a substantial uplift in the number of patients representing the strong growth of nearly $42.5 million quarter-on-quarter. Ultimately, that is driven by strong prescriber growth.

What we have said is that when you look at the total number of prescribers launched to date of ARCALYST for recurrent pericarditis in Q3, or I should say at the end of Q3, we had around 5,450 total prescribers. That is an uplift of around 450 quarter-on-quarter. Again, it is really showing very strong growth. Now we have around 30% of that group who are repeat prescribers, which is up by around 170 prescribers. Historically, we have said that the split between the first and second recurrence is about 80% of prescriptions in the second plus recurrence and 20% in the first, but we have not updated that data on a very frequent basis, as a lot of it comes from kind of ad hoc market research that we do.

Clearly we are showing pretty strong growth in Q3. A lot of that is down to the refined targeting that we have with our field team, the DTC campaign in a very targeted approach, and also just broader dissemination of the ACC concise clinical guidance and really just empowering physicians on this new way of treating the disease.

Thanks, Peter.

Thank you, Geoff, for your question. I will tackle this first part with regard to the transition, if you will, from ARCALYST to KPL-387. I think that our position with regard to the management of the disease is that blockade of IL-1 alpha and IL-1 beta is critical to maintaining disease control and to gaining the disease control as a monotherapy. In that sense, we are particularly excited about the KPL-387 program because it adds to the optionality of what is available to patients and physicians in terms of treating this disease.

That efficacy ultimately remains to be demonstrated in the phase III pivotal trial, which is ongoing. But importantly, what we have going on as well is the 212 study or the KPL-387 transition to monotherapy dosing and administration study, which is really designed to look at the mechanics of how to transition from one existing therapy to KPL-387 monotherapy at the 300 mg monthly dose level. That includes NSAIDs and colchicine, corticosteroids or IL-1 pathway inhibitors, including anakinra and rilonacept.

All of those different transition regimens are studied and are evaluated in the study and then go on to over a 16-week primary endpoint period. So it's really about that transition, and that then informs the label with regard to telling or informing physicians how they can make that transition. In terms of the patient profile, it's really about the optionality for the patient and the physician to choose which effective therapy is considered to be best for them.

Geoff, in regards to your question on maximizing value and cash position, I can tell you what drives us each and every day is the potential to increase that overall maximum value. There's so much kinetic energy within the company that's focused on that. We've talked about, obviously today, the growth with ARCALYST, and we continue to be very excited about the future potential there. We talked about the latest penetration rate at being, in some ways, only 23%.

Equally, obviously, across the development portfolio with KPL-387 and 1161, as we've talked about, really moving now into what obviously is a phase III pivotal study for 387, being very excited about being in the clinic with 1161 later this year. As you see, those latter two programs were homegrown. So we continue to look at other additional value-creating opportunities, both internally but also externally. I think we've been very judicious and very thoughtful about capital allocation.

We do look at BD opportunities, but as you can imagine, with our commercial products, with our pipeline, the bar is exceedingly high. That said, we're a very pragmatic bunch, and we do look at where the value could come from all the time. It's what drives us, essentially. So rest assured, we know how to capital allocate. We know where best to drive value, and we'll continue doing that and ultimately keep executing.

Thank you very much. Thanks, everybody, for dialing in today. Clearly a lot of excitement, ongoing execution, and very excited about the future. The team and I will keep driving for future success for patients and for creating that additional value. Thank you.