Karyopharm Therapeutics Inc. (NASDAQ:KPTI) Q4 2025 Earnings Call Transcript

Karyopharm Therapeutics Inc. (NASDAQ:KPTI) Q4 2025 Earnings Call Transcript February 12, 2026

Karyopharm Therapeutics Inc. beats earnings expectations. Reported EPS is $-2.23, expectations were $-2.26.

Operator: Good morning. My name is Ludi, and I will be your conference operator today. At this time, I would like to welcome everyone to the Karyopharm Therapeutics Inc. fourth quarter and full year 2025 financial results conference call. There will be a question and answer session to follow. Please be advised that this call is being recorded at the company’s request. I would now like to turn the call over to Brendan Strong, Senior Vice President, Investor Relations. Please go ahead. Good morning.

Brendan Strong: And thank you all for joining us on today’s conference call to discuss Karyopharm Therapeutics Inc.’s fourth quarter and full year 2025 financial results and recent company progress. We issued a press release this morning detailing our financial results for the fourth quarter and full year 2025. This release, along with a slide presentation that we will reference during our call today, are available on our website. For today’s call, as seen on Slide two, I am joined by Richard Paulson, Reshma Rangwala, Sohanya Cheng and Lori Macomber who will provide an update on our results for the fourth quarter and full year 2025 and discuss recent clinical developments. Before we begin our formal comments, I will remind you that various remarks we will make today constitute forward-looking statements for purposes of the safe harbor provisions under the Private Securities Litigation Reform Act of 1995 as outlined on Slide three.

Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including those discussed in the Risk Factors section of our most recent Form 10-Q or 10-Ks on file with the SEC, and in other filings that we may make with the SEC in the future. Any forward-looking statements represent our views as of today only. While we may elect to update these forward-looking statements at some point in the future, we specifically disclaim any obligation to do so even if our views change. Therefore, you should not rely on these forward-looking statements as representing our views as of any later date. I will now turn the call over to Richard Paulson. Please turn to Slide five. Thank you, Brendan, and good morning, everyone.

Thank you for joining us today. Here in 2026, Karyopharm Therapeutics Inc. is in a defining phase marked by important late-stage clinical milestones, continued disciplined execution, and the opportunity to meaningfully expand the impact and scale of our oncology franchise. Today, selinexor has an established durable, commercial foundation of multiple myeloma within a highly competitive treatment landscape. That business continues to support the company and provide important experience as we advance into new treatment areas. Looking ahead, we see the most significant near-term driver of value in myelofibrosis, with endometrial cancer representing a subsequent opportunity to further expand the franchise. In myelofibrosis, we remain on track to share top-line data from our Phase III SENTRY trial in March.

SENTRY was designed to address a clear unmet need by evaluating selinexor as part of a combination approach in a setting where treatment options remain limited. Over time and through clinical experience, we have meaningfully optimized how selinexor is used, including dose refinement and proactive supportive care, resulting in a more manageable and predictable tolerability profile. As we approach this important data readout, our organization is energized and well positioned to deliver on this opportunity. In endometrial cancer, we remain on track to report top-line data from our Phase III EXPORT EC042 trial in mid-2026. This biomarker-driven program targets a defined patient population with limited effective treatment options and represents an important opportunity to expand the long-term commercial profile of the franchise beyond hematological malignancies.

From a financial perspective, we continue to manage the business with discipline. As previously disclosed, our cash runway extends into the second quarter, which aligns with key near-term clinical milestones. We have been deliberate in how we sequence spend across the portfolio and we are actively evaluating a range of financing and strategic options to maintain flexibility and align capital decisions with value creation. With that context, I would like to first turn the call over to Reshma Rangwala, our Chief Medical Officer, who will provide a detailed update on our clinical programs and upcoming milestones. Following Reshma, Sohanya Cheng, our Chief Commercial Officer, will discuss how we are preparing from a commercial and go-to-market perspective.

Then Lori Macomber, our Chief Financial Officer, will review our financial results and discuss our financial guidance for 2026. After those updates, we will return for additional discussion and Q&A.

Operator: Reshma?

Reshma Rangwala: Thank you, Richard. I am incredibly excited by the near-term opportunity to read out two Phase III trials that could establish new standards of care in two areas of high unmet need. Start with myelofibrosis where we will have data next month. As seen on Slide eight, I would like to emphasize substantial need for new treatment options for patients with myelofibrosis. JAK inhibitors are the only approved therapies, and while they may decrease burden and lead to very modest spleen reduction, relevant JAK inhibitors including ruxolitinib, the standard of care in frontline myelofibrosis, do not target all of the relevant pathways implicated in myelofibrosis, including NF kappa beta, p53, and fibrosis-inducing pathways.

As a result, frontline treatment with monotherapy JAK inhibitors do not adequately address the relevant drivers of pathogenesis in myelofibrosis. On Slide nine, our confidence in selinexor’s potential in myelofibrosis is based upon a substantial body of preclinical, nonclinical, translational, and clinical efficacy as well as safety datasets. These data suggest XPO1 inhibition is a key mechanism that may facilitate potential synergy with ruxolitinib and other drugs relevant in myelofibrosis. This multi-targeted approach enables treatment of the underlying mechanisms that lead to myelofibrosis and we believe may lead to meaningful efficacy across the key treatment drivers as well as the generally safe and manageable side effect profile. As seen on Slide 10, while JAK inhibitors directly inhibit the JAK-STAT pathways, multiple other pathways downstream of JAK-STATs support malignant clone proliferation and survival, bone marrow fibrosis, cytokine storms, and proliferation of abnormal megakaryocytes.

These pathways include NF kappa beta, PI3 kinase, AKT mTOR, and TGF beta. A multifaceted approach with dual XPO1 and JAK inhibition simultaneously target upstream and downstream effectors of the JAK-STAT pathway, enabling apoptosis or cell death of the malignant clones. Let us now focus on the key treatment drivers in myelofibrosis, as seen on Slide 11. Spleen reduction, symptom improvement, and lower rates of grade 3+ anemia. First, spleen volume reduction. Note that only approximately one third of patients achieve a spleen volume reduction of greater than 35% with ruxolitinib alone. In contrast, our Phase I data suggests that the combination could more than double the SVR35 rate at 79%. Second is symptom improvement. Data from this trial also showed an average 18.5 improvement in absolute TSS at week 24 relative to baseline, which suggests that combination could provide a meaningful improvement over the 11 to 14 points achieved by patients on ruxolitinib as observed in the Phase III II and TRANSFORM-1 trials.

Keep in mind that our 18.5 improvement excludes fatigue, whereas the numbers from the other trials include fatigue. So in reality, the difference could be even greater. Third is lower rates of grade 3+ anemia. The data that we presented in June at EHA from our Phase II, 35 monotherapy trial showed lower rates of all grade and grade 3+ anemia for the selinexor arm as compared to physician’s choice, in myelofibrosis patients previously treated with JAK inhibitor therapies. Our initial blinded safety data from the first 61 patients enrolled in SENTRY also suggests lower rates of grade 3+ anemia when selinexor is combined with ruxolitinib compared to historical ruxolitinib data. Meaningful improvement of these treatment drivers require disease modification or elimination of the underlying mechanisms leading to development of an enlarged spleen, constitutional symptoms, and worsening cytopenias.

Data observed from selinexor monotherapy studies in a pretreated myelofibrosis population, as well as our Phase I combination data in JAK inhibitor naïve myelofibrosis, suggests meaningful reductions in key cytokines critical to myelofibrosis pathogenesis, symptom development, and anemia, as well as improvements in bone marrow fibrosis, increased mutational burden. Improvement in these markers of disease monster alone and in combination may lead to improvement in the key hallmarks of the disease including enlarged spleen, cytopenias, and symptoms. Turning to Slide 12, we are eagerly awaiting the readout from our Phase III SENTRY trial next month. Everything within our control to optimize SENTRY for success. As we have previously discussed, we believe that we have, including focusing on the relevant symptom domains and the analysis of PFS can be most accurately evaluated in a randomized trial analyzing TSS by estimating in approximately 350 patients approximately 22.5 which could be the highest baseline TSS observed in a frontline myelofibrosis Phase III trial.

Depending on the outcome of our data in myelofibrosis, we also have a significant opportunity to expand into other myeloproliferative neoplasms as outlined on Slide 13. This includes the potential to expand into polycythemia vera and essential thrombocythemia with eltenexor, our leading next-generation XPO1 inhibitor. Let us now turn our attention to endometrial cancer on Slide 15.

Reshma Rangwala: In the Phase III EXPORT EC042 trial, the number of PFS events observed to date are consistent with our projections giving us confidence in our ability to share top-line data in mid-2026. In light of the near-term proximity of these data, I wanted to go back and remind everyone about the treatment landscape, our data from our last trial, and recap our current trial design. Our Phase III trial is recruiting patients with p53 wild-type endometrial cancer. Given that checkpoint inhibitors are entrenched in the treatment landscape for patients with dMMR tumors, the trial has been updated to first evaluate the primary endpoint of PFS in patients with p53 wild-type pMMR tumors or p53 wild-type dMMR tumors but medically ineligible to receive a checkpoint inhibitor.

If positive, PFS will then be evaluated in all with p53 wild-type tumors. As discussed previously, the long-term follow-up data from our Phase III SIENDO trial indicated that women in the exploratory subgroup with p53 wild-type endometrial cancer and pMMR tumors, roughly half of all patients, experienced a progression-free survival with selinexor as a maintenance therapy following chemotherapy, which exceeds the overall survival that inhibitors have demonstrated in the same population. Let us review some of our long-term follow-up data from our last Phase III trial in endometrial cancer. Slide 16 shows a very encouraging signal in the p53 wild-type subgroup with a hazard ratio of 0.44, and a median PFS benefit of 28.4 months largely due to the early separation of the curves.

These data have only strengthened with time and suggest a similar trend may be observed in our ongoing Phase III trial. These results were even more impressive in the subgroup of patients with p53 wild-type pMMR tumors, as shown on Slide 17, the long-term follow-up data from this prespecified exploratory subgroup showed a hazard ratio of 0.36 and a median PFS benefit of 39.5 months. Similar to the broader 18 shows the safety profile at the time of the long-term follow-up, which is something that we will expect to improve when we report data from our ongoing Phase III trial. As you look at these data, keep in mind that SIENDO was evaluating 80 mg of selinexor once weekly. And while antiemetics were used at time, the mandated use of dual antiemetics during the first two cycles of therapy was not part of the clinical trial protocol.

This is a key difference when you think about the design of our current Phase III, where we are using a lower dose of selinexor at 60 mg once weekly, and dual antiemetics are mandated during the first two cycles of therapy. That takes us to Slide 19, which contains the trial design of our Phase III EXPORT EC042 trial where selinexor 60 mg is being evaluated as a maintenance therapy in patients with p53 wild-type endometrial cancer. The primary endpoint for the trial is progression-free survival as assessed by the investigator. As I mentioned earlier, event accrual is consistent with our projections, and we remain on track to share top-line data in mid-2026. I am incredibly excited by the opportunity presented by both of these Phase III trials to establish new standards of care in two areas of high unmet need.

I will now turn the call to Sohanya. Thank you, Reshma. As shown on Slide 21, our commercial organization executed well in 2025 within the highly competitive multiple myeloma market. XPOVIO net product revenue grew to $32.1 million in the 2025 and $114.9 million for full year 2025. We expect to continue to deliver revenue growth this year and are guiding towards $115 million to $130 million of XPOVIO net product revenue in 2026. Demand for XPOVIO was consistent year over year in 2025 with the community setting continuing to drive approximately 60% of total U.S. sales. XPOVIO continues to be positioned in both the community and academic settings as a flexible therapy with a differentiated mechanism of action oral convenient option. Additionally, given the emergence of new T-cell engaging therapies, and our growing body of evidence around the role of selinexor in potentially preserving the T-cell environment, XPOVIO continues to be utilized in the peri T-cell engaging therapy setting.

Let us turn to Slide 23. As we work to expand beyond multiple myeloma, let us now focus on myelofibrosis, where selinexor has the potential to play a very different role where the patient populations, competitive dynamics, the dose of selinexor, and potential impact on patients are fundamentally different. This is why our commercial opportunity in myelofibrosis is so much greater. Taking a closer look at dosing and patient population differences between the two diseases, it is important to recognize that the side effect profile often associated with XPOVIO stems largely from its use at higher doses in multiple myeloma following our initial approval. Those historical concerns accurately reflect how selinexor is expected to be used at a lower dose with dual antiemetics in frontline myelofibrosis if approved.

The other fundamental difference between the two diseases is the unmet need and competitive landscape. In myelofibrosis, the only treatment options that patients currently have are JAK inhibitors, with ruxolitinib monotherapy being the standard of care for the past 15 years and only about one third of patients that receive ruxolitinib volume reduction of 35% or more with two thirds of patients not adequately responding. As Reshma outlined, our data highlights offer opportunity to meaningfully improve patient outcomes by increasing the proportion of patients that achieve rapid, deep, and durable spleen volume reduction, as well as symptom improvement and lower rates of grade 3+ anemia while also potentially modifying the underlying disease. Slide 24 provides an overview of our opportunity to be the new market leader with the first ever frontline combination therapy as we combine with the current market leader to offer better outcomes for patients.

As you look at the overall prevalent market there are 20,000 patients living with myelofibrosis in the U.S., which represents a multibillion dollar marketplace, with approximately 6,000 newly diagnosed patients each year. Our commercial efforts will focus on the approximately 4,000 newly diagnosed patients with intermediate to high risk myelofibrosis that have a platelet count above 100,000. Based on the market research that we have conducted, 75% of physicians expressed intent in treating patients with a combination therapy. For duration, we are assuming that we can improve upon the 13-month real-world duration of treatment for ruxolitinib. Taking all of this into account, we believe that our peak revenue opportunity may approach $1 billion annually in the U.S. alone.

Turning to Slide 25. We have the capabilities in sales, market access, marketing, and medical affairs to support a launch in myelofibrosis. The team that we have assembled has deep experience in hematological oncology and rare disease launches. This group plus the robust teams that support them will allow us to launch rapidly. Our current sales organization has deep relationships and experience with accounts that will be key to our launch. As outlined on Slide 26, 70% of myelofibrosis patients are treated in the community setting. The majority of these patients are treated at five large community networks, such as U.S. Oncology and Florida Cancer Specialists, and approximately 200 other large community accounts. Academic institutions represent the other 30% of patients and more than 70% of these patients are treated at the top 50 academic institutions.

Importantly, a majority of the top 50 academic institutions are participating in SENTRY and/or SENTRY-2. So the clinical care teams that work with myelofibrosis patients in these institutions are already very familiar with selinexor plus ruxolitinib for frontline myelofibrosis patients. As we focus on the concentrated group of accounts outlined on this slide, we believe this will allow us to launch rapidly. Turning now to Slide 27. We are energized by the opportunity to reshape frontline myelofibrosis treatment by pairing selinexor with the current standard of care. Today, two thirds of patients still fail to reach SVR35 on ruxolitinib, an unmistakable unmet need. Our selinexor–ruxolitinib combination is a convenient all-oral regimen. Our teams are already engaging the key accounts, positioning us for a fast, efficient launch.

Just as importantly, selinexor fits seamlessly into existing workflows. No new testing. No operational hurdles. No disruption to how patients receive care. That simplicity makes adoption far easier. With positive data and regulatory approval we will be ready to drive rapid meaningful uptake and deliver a therapy with the potential to change the trajectory for patients. Now I will turn the call over to Lori. Good morning, everyone, and thank you, Sohanya. Turning to our financials on Slide 29. Total revenue for the 2025 was $34.1 million, an increase of 11.8% compared to the 2024. For the year, total revenue was $146.1 million, a slight increase from 2024. U.S. XPOVIO net product revenue for the 2025 was $32.1 million, an increase of 9.6% compared to the 2024.

For the year, U.S. XPOVIO net product revenue was $114.9 million, an increase of 1.9% from 2024. Gross-to-net provisions for XPOVIO were 26.9% in the fourth quarter and 31.2% for the calendar year 2025. License and other revenue was $2.0 million in the fourth quarter and $31.2 million for the full year 2025. Keep in mind, our full year revenue included $15.0 million of R&D reimbursement from Menarini, and 2025 was the last year we will receive this reimbursement. Remaining $16.2 million in 2025 was related to royalties, or milestones earned from our international partners including Menarini. Turning to expenses. We remain disciplined in managing operating expenses and allocating capital to our pipeline. This focus continues to translate into solid quarterly and full year financial performance.

Research and development expenses for the 2025 were $27.7 million, a decrease of 17% from the 2024. For the full year, research and development expenses were $125.6 million, a decrease of 12% from 2024. These decreases were driven largely by lower personnel following previously implemented cost reduction initiatives and focused clinical trial expenses as we prioritize capital allocation to our Phase III myelofibrosis and endometrial cancer programs. Selling, general, and administrative expenses were $22.8 million for the quarter, a decrease of 16% compared to the 2024. For the full year, SG&A expenses were $105.2 million, a decrease of 9% from 2024. These decreases primarily reflected the continued benefits of our cost reduction initiatives.

Lori Macomber: Taken together, our law firm operations improved by approximately 43% in the 2025 compared to the 2024. And improved 24% in the full year 2025 compared to 2024. Interest expense was $12.6 million in the fourth quarter and $45.8 million for the full year. Both amounts were an increase from the comparable periods in 2024 reflecting higher outstanding debt, and higher interest rates as part of our refinancing in October. Other expense was $10.0 million in the 2025, compared to $10.1 million of other income in the 2024. For the full year, other income was $0.2 million compared to $28.4 million of income in the full year 2024. This nonoperational item is primarily driven by reoccurring noncash fair value remeasurements of embedded derivatives and liability-classified common stock warrants related to the refinancing transactions completed in the 2024 and the 2025.

This, combined with the $62.4 million loss on the extinguishment of debt in 2025 compared to the $44.7 million gain on the extinguishment of debt in 2024, were the primary contributors to the higher net loss and lower earnings per share in 2025 versus 2024. Importantly, both items are noncash and nonoperational in nature. As a result, we reported a net loss of $102.2 million, or $5.71 per share on a GAAP basis in the 2025, and a net loss of $196.0 million, or $17.93 per diluted share for the full year 2025. More than half of the full year loss was driven by below-the-line items including the loss on extinguishment of debt, and interest expense, which are largely noncash in nature. Excluding these items, our underlying operating performance continues to demonstrate meaningful improvement.

Finally, we ended the year with $64.1 million in cash, cash equivalents, restricted cash and investments compared to $109.1 million as of December 31, 2024. Based on our current operating plans, our guidance for the full year 2026 is as follows: total revenue of $130 million to $150 million consisting of U.S. XPOVIO net product revenue and license, royalty, and milestone revenue expected to be earned from our partners, primarily Menarini and Antengene. U.S. XPOVIO net product revenue to be in the range of $115 million to $130 million. R&D and SG&A expenses to be in the range of $230 million to $245 million. We expect our existing liquidity including the revenue we expect to generate from XPOVIO net product sales, as well as revenue generated from our license agreements, will enable us to fund our current operating plans into the second quarter of this year.

I will now turn the call back to Richard for some final thoughts. Thank you, Reshma, and Lori. As we have discussed today, Karyopharm Therapeutics Inc. is well positioned as we approach pivotal data that will inform the next phase of the company. We have a durable commercial foundation of multiple myeloma, and we are approaching pivotal data from our late-stage clinical programs that have the potential to significantly expand the role and impact of our oncology franchise, beginning with myelofibrosis in March, and extending into endometrial cancer in the middle of this year. We have continued to refine how our programs are developed and executed, applying clinical experience, optimizing how our therapies are used, and ensuring our Phase III programs reflect what we believe is the right balance of efficacy and tolerability for the settings we are targeting.

From a capital perspective, we remain disciplined and deliberate. We are managing the business with a clear focus on near-term value-creating milestones, while maintaining flexibility and optionality as we consider financing and longer-term strategy. Ultimately, our priorities are straightforward. Execute well, generate high-quality data and allow these results to define the next phase of the company. We believe this approach best serves patients, investigators and shareholders alike. We will now open the call for questions. Operator?

Operator: Thank you. And ladies and gentlemen, we will now begin the question and answer session. To ask a question, you may press the star followed by the number one on your telephone keypad. If you are using a speakerphone, please pick up your handset before pressing the keys. To withdraw your question, you may press star followed by the number two. And we kindly ask you to please limit yourself to one question and one follow-up. With that, our first question comes from the line of Colleen Margaret Kusy with Baird. Please go ahead.

Q&A Session

Colleen Margaret Kusy: Great. Good morning. Thanks for taking our questions, and congrats on all the progress. Very excited for the upcoming data we will see next month. Maybe we can start there. Obviously, the 60 mg data has yeah. That we have seen so far is invest in class. I think as a lot of people are doing a little bit more work ahead of the readout, there have been some questions coming up from investors on just on the 40 mg dose and data we have seen there. So maybe just can we start there? Just any notable difference in exposure? Anything else you think is driving that difference in activity that you have seen for the 40 mg versus the 60 mg in the Phase I?

Richard Paulson: Yes. Thanks, Colleen. I think, obviously, our dose is focused on the 60 milligrams and looking at our Phase III trial. But I will let Reshma maybe just talk to that broadly, but I think people should be very focused on the data. Efficacy, safety, and tolerability we have with the 60 milligram in combination with rux.

Reshma Rangwala: Yeah. Thank you, Colleen and Richard. So it goes back to our Phase I data in which we evaluated both the 60 mg as well as 40 mg. When you look at the efficacy and safety, there is a clear benefit risk in favor of the 60 milligram cohort as compared to the 40, largely due to the fact that efficacy, both from an SVR as well as TSS, was maximized in the 60 milligram group as compared to the 40 milligram group. Now, when you look at the safety, though, you do not see as stark of a difference. Numerically, yes. Both the heme and non-hemes are slightly higher with the 60 milligram as compared to 40, but you do not see that substantial dose response as compared to, again, what I described in the efficacy. So in total, again, when you look at the efficacy and safety data, it really is in favor of that 60 milligram group.

Then layer in the pharmacokinetic data and, therefore, exposures are higher with that 60 milligram group as compared to the 40. So really, the totality of the data from the clinical efficacy, safety, ClinPharm, and then, of course, we have got multitude of preclinical data, translational PD markers that really suggest that 60 milligrams is the right dose in myelofibrosis. Hence, the reason that we have taken that forward in our Phase III. And then, obviously, you are the first potential combination in frontline MF, which is a exciting opportunity. Novartis, a potential competitor potentially just kind of announced some new plans moving forward in MF. Just kind of curious your thoughts on the read through there. Would think, obviously, follows your strategy of enrolling highly symptomatic patients but just curious your thoughts on the read through there.

Richard Paulson: Yeah. Thanks, Colleen. Yeah. I think you highlighted it. It really it does talk to the importance of having the right patient population in the trial, which I think we have delivered very well. And overall, really, the continued investment in myelofibrosis space really talks about the unmet need and the significant value that that is seen in myelofibrosis market. So you know, I think as we look at it, you know, regarding the EU and Novartis has indicated they may be moving forward and filing there. That may indicate that the EU regulatory agencies are more focused on 35 and potentially showing you know, more regulatory flexibility, less focus on symptoms. But you know, given our top-line readout data is going to happen in March, we would look to be filing rapidly with our data, obviously engaging in both the U.S. and globally.

And so I think this really gives us the opportunity to establish ourselves pending positive data as a standard of care in myelofibrosis, you know, given the fact that Novartis has indicated that they would run another trial for the U.S. And that trial would not read out for a number of years and gives us a significant amount of time to establish ourselves well and become the standard of care in frontline myelofibrosis.

Colleen Margaret Kusy: Awesome. And then one more quick one if I can. Just, if you could the comments a little bit about the strategy for eltenexor and other MPNs if MF is positive? Just strategy would look like there and and what the IP is. Could you remind us for eltenexor versus onixor?

Reshma Rangwala: Yeah. I will take the first question, and then I will pass over the IP to Richard. But yes, eltenexor is a second-generation XPO1 inhibitor. So just like selinexor, it too is going to inhibit XPO1. It has a couple of differentiating properties, lower IC50s as well as lower penetration through the blood-brain barrier. That has opportunities to lower the dose, potentially dose more frequently, also have a better safety profile, profile. Eltenexor has already been evaluated in a Phase III trial, so we do have some, you know, very encouraging preliminary data, albeit in other tumors outside of the MPNs. I think where we look at the next opportunity is to go beyond MF. Right? We know that MF is just one of multiple MPNs. We have got some really interesting preclinical data that also suggests that XPO1 may be relevant in other MPNs, including PV as well as and so that, I think, would be our next opportunity.

Is to expand again beyond MF and start to look at some of these other more chronic diseases like the ones that I just mentioned.

Richard Paulson: Yeah. And from a patent perspective, obviously, it is early days yet with regards to our overall strategy there. But you know, right now, with eltenexor, the patent, it goes into mid-2034. But as a reminder, we have not yet yet applied for any patent term extension or patent term adjustment which would extend it, you know, into 2039. So lots of opportunity for us as we continue to move forward and develop in that in that space.

Colleen Margaret Kusy: Great. Thanks so much for taking our questions. Six here for the data next month.

Richard Paulson: Thanks, Colleen.

Operator: Thank you. And the next question comes from the line of Yichun Qian with Cantor. Please go ahead.

Yichun Qian: Hi, folks. Appreciate the updates here. Greatest progress in timelines remain intact. Just had a question with regards to the blinded safety data. And just given that you have been able to provide baseline characteristics on a blinded basis with the trial now fully enrolled, curious if there has been an opportunity to kind of refresh that look and if there has been any kind of material change there with regards to discontinuation rates or other AEs like the nausea and anemia and thrombocytopenia.

Reshma Rangwala: Hey, Yoni. Thanks for the question. So, no, we have not updated anything beyond what we have publicly disclosed in the past. So, you know, what we have said in the past is, you know, the baseline demographic is disclosed in the ASH abstract, included approximately 320 patients, was very consistent with our expectations for population to be enrolled in a frontline myelofibrosis. With that said, though, we did have an opportunity to update the TSS in approximately 350 patients. Again, you know, something that I have commented before in the past. And that TSS evolution, that baseline TSS evolution without fatigue is, again, really nice. Approximately 22.5 potentially could be the highest baseline TSS, which is something that we were actively striving for.

In terms of the blinded safety data, no, we have not done a refresh. We are looking forward to the data next month where we can definitively look at the data across the two arms. Those two, I think, are very encouraging and potentially suggest that patients treated with a combination could have lower grade 3+ anemia. This is, again, based upon extrapolations relative to historical ruxolitinib data, as well as very manageable non-heme toxicities including the GI toxicities, nausea, as well as elaborate there. What is kind of the general.

Yichun Qian: Protocol? And if there is any kind of high level view that you can provide with regards to rux dosing and and how in line it is with the label.

Reshma Rangwala: Absolutely. So the SELE dose can be reduced. So it can go from 60 to 40 to 20, and then, yes, you know, of course, if the AEs persist, it can be discontinued. Those dose modification guidelines are well specified within the protocol. The ruxolitinib dose modifications are really based upon the country’s local label, right, which by and large are very consistent with the U.S. USPI. So the starting dose is going to be based upon the patient’s baseline platelet count, and then any kind of dose modifications, including reductions, interruptions, and even discontinuations, again, should be followed per the U.S. So we are very strict about that in our protocol. Now given the fact that this is a combination therapy, what we suggest to our investigators is to modify based upon what I call the flavor of the AEs. So if a patient first experiences a hematologic toxicity, for example, anemia, thrombocytopenia, very well described for ruxolitinib, we guide them to modify the ruxolitinib dose first, again, per the U.S. If they experience a non-heme toxicity, then we suggest that they modify selinexor dose.

So we try to keep it very easy for the investigator just based upon the kind of AE that the patient experiences.

Yichun Qian: Got it. Okay. And one one last quick one. Just with regards to SENTRY-2, could you comment there a little bit on kind of the strategic thought there and kind of utility of that data and what you are hoping to show and how that might tie in with future label extensions within MF?

Richard Paulson: Yeah. I can talk to that. Yeah. Mean, overall, obviously, enabling trial is our Phase III frontline combination with ruxolitinib. But really importantly, when we look at the overall efficacy and I think the activity of selinexor, we have seen in a number of our trials really strong monotherapy data. And also, we do know that it is important to be able to expand beyond ruxolitinib in the future. Potentially with selinexor to really play a foundational role across myelofibrosis first and potentially across other MPNs. So our Phase II is really one where we are letting patients start at the platelets greater than 50,000. The 50,000 and above is we just modified the protocol. And within that, it is starting with selinexor as a treatment monotherapy.

And then you have the opportunity for patients to be able to add on other JAK inhibitors depending on the need, so they may not need to. But if they do need to, they can add on their JAK inhibitors. And we do know that selinexor is a drug that is able to be partnered with many other drugs. So I think, you know, pending positive data with our Phase III frontline combination with rux, our view would be, you know, to read out the Phase II data, and look at that as an opportunity to really expand from a guideline perspective and enable physicians much more flexibility and the opportunity to establish, you know, selinexor in combination with multiple JAK inhibitors and/or selinexor to be able to treat patients potentially as a monotherapy. But, again, that is an opportunity to expand in the future.

An area that I think we are quite excited about and is moving forward well. Anything you would add on to that, Reshma?

Reshma Rangwala: No. Nothing. That is great.

Yichun Qian: Perfect. Alright, guys. Really appreciate the updates, and best of luck here in the near in near term.

Brendan Strong: Thanks, Yoni.

Operator: And the next question comes from the line of Brian Corey Abrahams with RBC Capital Markets. Please go ahead.

Brian Corey Abrahams: Hey. Good morning. Thanks for taking my question, and look forward to an exciting next couple of months. You reported the Phase III baseline characteristics at the ASH conference in an abstract. And it looks like if you look at the risk status, if you look at spleen volume, the baselines the baselines the patient population looks somewhat milder than what was in the Phase I/II. And then while the I think you pointed out that the TSS score is actually substantially higher, there is a pretty wide range, including patients going down to scores as low as two. So can you maybe talk about what some of those similarities but also differences might mean with regards to, you know, the potential to show as why the delta in the in the Phase III?

Reshma Rangwala: Thanks. Sure. Thanks, Brian. You are correct, right? Sort of like if you compare the patient populations in the Phase III, Phase I, I would agree. It is a little bit milder. I think the other aspect that is different is even the baseline hemoglobin. Right? So it was approximately 10 grams. Median was 10 grams in the Phase I. It is approximately 11 grams in the Phase III. So I think by and large, right, yes, this potentially could be a less sick patient population. You know, with that said, though, I do not think it is going to have any impact on the efficacy. Right? And I say that because even when we look at the subgroups, from our Phase I from an SVR perspective, there really is a very nice consistency, including across all of the dips.

From INT-1 all the way up until high risk. And even by hemoglobin. So I think it really suggests that there can be meaningful benefit across all of the different subsets of patient populations to, of course, people that are going to have far more difficult to treat disease versus those that are have a little bit more mild disease.

Brian Corey Abrahams: No. That is really helpful. Thanks. And then do you have any sort of updated feedback from either KOLs or from regulators on that is maybe shaped your view on what might be a reasonable threshold for symptomatic improvement just in the in the case that you show statistically significant spleen reductions, but do not quite show, get to statistical significance on symptoms. What would be the bar to still potentially proceed with the filing, assuming there are not any safety surprises or anything like that?

Reshma Rangwala: Sure. You know, so our goal is to really show statistical significance for both SVR as well as absolute TSS. Right? You know, those are the bars that are included in our statistical analysis plan as well as discussed with the FDA. We think that profile again statistically significant improvement both for the SVR, TSS, in the context of a very manageable safety profile, is really the ideal profile for a new combination therapy, the only combination therapy that would be available for these patients with MF. Even take it one step further, when we talk to our KOLs, right, they do emphasize that SVR is going to be their primary treatment driver, largely because there are, you know, multiple datasets, multiple meta-analyses, that really suggest that the deeper, the more rapid, the more durable the SVR that can be achieved, the more that it may correlate with long term.

They are very focused on that spleen volume reduction, and while they say, yes, symptoms are important, you are really, for them, they just want to see some kind of benefit. Benefit above and beyond ruxolitinib. So, again, I think even if you have that outcome in which SVR is positive, TSS is numerically improved, that is a profile that they would be very happy with and clearly would even advocate for the NCCN guidelines to adopt. So you know, I think that is very encouraging from their and a very important voice, right, in the MF space. From a regulatory perspective, they have never commented. Right? They have never commented on what that minimum delta would be. I think, again, I think statistical significance is what we are, you know, striving to achieve here.

Got it. That is super helpful. And then maybe one more if I could squeeze it in.

Brian Corey Abrahams: Could you just remind us on the regularity of, I guess, DSMB or interim safety looks here and whether or not you would expect that would pick up on any imbalances in the transformation. Thanks.

Reshma Rangwala: Yes. So the DSMB does evaluate the data on a regular basis, approximately every four to six months. It is something that we do across all of our clinical trials. And, yeah, they would. You know, they get the totality of the safety data from all AEs, grade 3, 4, SAEs, and, of course, transformations as well. So far, they have not, you know, mentioned anything. And as I mentioned previously, even with the futility analysis, they did suggest that this study continues without modification.

Brendan Strong: Thanks again.

Richard Paulson: Thank you, Brian.

Operator: And the next question comes from the line of Maury Raycroft with Jefferies. Please go ahead.

Maury Raycroft: Hi, good morning. Thanks for taking my questions. Maybe as a follow-up to one of the earlier ones, for the 61 patients in the futility analysis group in SENTRY, what can you say about dose reductions you saw for selinexor and/or ruxolitinib? And even though you have been clear that we should not rely too much on extrapolating based on these patients, can you contextualize how the dose reductions compared to your Phase I? And how the rux dose reductions could compare to other myelofibrosis Phase III studies.

Reshma Rangwala: Sure. Great question, Maury. I have not commented on the dose reduction from the first 61 patients, specifically for the ruxolitinib, largely because, you know, as you know, the starting dose is going to be very variable again based upon the patient’s baseline platelet count. Extrapolating, you know, the rux dose intensity and the dose reductions in the context of a blinded safety data where that starting dose is very variable, again, can be very challenging. And so, again, it is not meaningful output at this time. You know, let us just wait until the top-line data. With that said, though, we have mentioned that the selinexor dose intensities, whether selinexor or placebo, does look really good. Amongst the 61 patients, the mean relative dose intensity was greater than 95%.

Maury Raycroft: Got it. Okay. That is helpful. And maybe just two quick clarification questions. For the first 61 patients, is there anything more you could say about where those patients were recruited from, which regions they came from?

Reshma Rangwala: Sure. They were globally. So they were they were going to they are globally recruited. Primarily North America as well as EU. And probably a few more. I do not have the exact numbers, will say, but I anticipate more patients coming from North America just because those were the first sites activated. But, yeah, just assume that this is going to be a population largely recruited, again, within Europe as well as North America.

Maury Raycroft: Got it. Okay. And for knowing that the date is going to be in March is really helpful. Just wondering if you are saying whether it is going to be earlier or later in March.

Richard Paulson: No. We think guiding to March is pretty strong. So we feel very good about that and continue to progress well, and then we will read the data out in March.

Maury Raycroft: Got it. Okay. Thanks for taking my questions.

Richard Paulson: Thanks, Maury.

Operator: And your next question comes from the line of Wei Ji Chang with Leerink Partners. Please go ahead. Just one. Hi, guys. Thanks for taking my question.

Wei Ji Chang: What are the key reasons for confidence in hitting on the TSF endpoint of the SENTRY study? Thank you.

Reshma Rangwala: Sure, Jonathan. Great. Great question. I think there are multiple different aspects that give us confidence. So you know, I go back to, you know, the studies the Phase I study’s original secondary endpoint was TSS-50. Right? When we have the opportunity to look at TSS-50 amongst that ITT, numbers were quite strong at approximately 59%, relative to historical ruxolitinib data that have read out, you know, sort of in the mid-40s. So a really nice improvement there. We then looked at absolute TSS, or the observed mean change at week 24 relative to baseline. These are going to be the actual values, not estimated, which is what is going to be coming from the Phase III. Those numbers too, very strong with an 18.5 improvement.

The size get it from the Phase I population, which was naïve treated with the combination, or even from our monotherapy study in which we evaluated selinexor as a monotherapy in that previously treated population, you really see very meaningful and rapid reductions in those substantially better than what is again been described for ruxolitinib where the improvement was only 11 to 14 points. So from a clinical perspective, you really have evidence of meaningful TSS improvement from both TSS-50 as well as absolute TSS. Now, the other part that really should be taken into consideration is cytokine levels as early as week four. So the fact that you see that cytokine decrease again explains why you also see that associated clinical benefit. So I think, like, really, those are going to be the key reasons why I have that confidence.

I think the other aspects that we cannot lose sight on is the FDA gave us the to change out the endpoint, right, from TSS-50, which we know is very crude measurement of symptom benefit, to a much more sensitive methodology in absolute TSS, which is, again, going to look at that mean change over time. And then the last part that I will just emphasize is that we are looking at TSS without fatigue, and the reason we are doing that is again, there is precedence with evaluating without fatigue. It was established by both ruxolitinib as well as fedratinib, but we also know that fatigue, it is just a very, very difficult domain to meaningfully evaluate. So I think again, being able to incorporate absolute TSS without fatigue as the key measure of improving symptoms is really a significant opportunity to be able to show that significant improvement relative to ruxolone.

Richard Paulson: And then, Jonathan, I will just close that because I think as Reshma talked to, we feel very good about that. And then as we have said, feel very pleased with the patient population we have enrolled. It is consistent with the population we had planned, and as we set our targets to ensure we had, you know, a meaningful baseline TSS, we have delivered on that with the TSS scores, you know, appear to be higher than MANIFEST and substantially higher than TRANSFORM, which, again, is what we intended to do. So I think we have set up the trial as well as we could and are extremely excited about reading this out next month in March.

Wei Ji Chang: Understood. Thank you.

Richard Paulson: Thanks, Jonathan.

Operator: And we have no further questions at this time. I would like to turn it back to Richard Paulson for closing remarks.

Richard Paulson: Thank you, operator, and thank you, everyone, again for your time and your continued interest in Karyopharm Therapeutics Inc. As you just heard, we are extremely excited to be reading out our top-line Phase III data in the frontline myelofibrosis with selinexor in combination with rux. And we look forward to engaging with you in March as we read that out. You for joining us today.

Operator: Thank you. Ladies and gentlemen, this concludes today’s conference call. Thank you all for joining. You may now disconnect.