Good morning. My name is Jason and I will be your conference operator today. At this time, I would like to welcome everyone to the Karyopharm Therapeutics Second Quarter 2023 Financial Results Conference Call. [Operator Instructions] Please be advised that this call is being recorded at the company’s request.
I would now like to turn the call over to Elhan Webb, Senior Vice President of Investor Relations..
Thank you, operator and thank you all for joining us on today’s conference call to discuss Karyopharm’s second quarter 2023 financial results and recent company progress. We issued a press release this morning detailing our financial results for the second quarter 2023.
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 2, I am joined by Richard, Reshma, Sohanya and Mike, who will provide an update on our results for the second quarter and recent clinical development.
Before we begin our formal comments, I will remind you that various remarks we will make today constitute forward-looking statements for the purposes of the Safe Harbor provisions under the Private Securities Litigation Reform Act of 1995, as outlined on Slide 3.
Actual results may differ materially from those indicated by these forward-looking statements, FLS, as a result of various important factors, including those discussed in the Risk Factors section of our most recent Form 10-Q, which is on file with the SEC and in other filings that we may make with the SEC in the future.
Any FLS represent our views as of today only. While we may elect to update this FLS 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 FLS as representing our views as of any later date. I will now turn the call over to Richard. Please turn to Slide 4..
Thank you, Elhan. Good morning, everyone and thank you for joining Karyopharm’s second quarter 2023 earnings call. Turning to Slide 5, we had a strong second quarter as we accelerate Karyopharm to its next stage of growth with our novel sign compounds selinexor and eltanexor.
As Reshma will discuss further, we are advancing a focused clinical pipeline with three ongoing Phase 3 pivotal studies based upon a strong foundation of supportive data, a recently obtained Fast Track designation of myelofibrosis, and a set of pivotal catalysts over the next 2 years.
With our current approved multiple myeloma indication in the U.S with selinexor, we continue to expand and shift into earlier lines. As Sohanya will discuss further, year-over-year total demand for XPOVIO continues to grow in a competitive multiple myeloma marketplace.
Selinexor is also expanding its global footprint with approvals and various indications in approximately 40 countries outside of the U.S., providing us with a growing stream of payments from royalties and milestones from our partners as launches move forward globally.
As part of our continued prioritization of our late stage clinical pipeline, we have taken additional actions to streamline our operations and optimize our cost structure.
As a result, we have reduced our workforce by approximately 20%, which is expected to enhance our financial strength, provide us with the capital needed to deliver on our three Phase 3 studies and maximize value for our shareholders. This was an extremely difficult decision given the direct impact this has on our employees.
However, after careful consideration, this action was imperative in order to further focus the organization on the near-term opportunities ahead of us. I am sincerely grateful for the tireless work and commitment of all colleagues who are being impacted and to the colleagues that will enable Karyopharm success moving forward.
As we move to Slide 6, presented here is an overview of the timing of the upcoming key data readouts, which we expect in 2024 and 2025. Each of our ongoing Phase 3 clinical trials, if successful, represents an incredibly meaningful growth opportunity for our organization with the potential to deliver roughly $2 billion in annual peak revenues.
Starting with multiple myeloma, a successful Phase 3 trial with SPD anticipated in the second half of next year would accelerate selinexor into the second line treatment and enable continued growth in multiple myeloma.
In endometrial cancer, we believe selinexor has the potential to transform the treatment paradigm for TP53 wild-type endometrial cancer patients, given the unprecedented data, which was presented at the Virtual ASCO Plenary Series last week, of which Reshma will speak to momentarily.
Finally, in myelofibrosis, we recently announced the initiation of our pivotal Phase 3, with the potential to transform the frontline treatment for patients with myelofibrosis as we build upon the rapid, deep and sustained responses we have seen thus far.
Collectively, we believe we have the potential to achieve multiple product approvals over the next 2 to 4 years as we deliver our next phase of growth, leveraging our proven and established commercialization and late stage development capabilities.
Shifting to selinexor’s position internationally on Slide 7, our continued global expansion with our partners provides further opportunities to treat patients in need with selinexor as our partners continue to commercialize and the launch in additional global territories.
Our license agreements with our partners provide us with a steady stream of revenues through growing double-digit future royalties and potential development and sales milestone payments of up to $400 million. Moving to Slide 8, I would now like to turn the call over to Reshma to expand further on our clinical pipeline progress.
Reshma?.
Thank you, Richard. I want to start off by highlighting our rapidly advancing pipeline on Slide 9, which includes three pivotal Phase III trials with selinexor that are enrolling in multiple indications of high unmet need. In addition, we are evaluating our second sign compound eltanexor in myelodysplastic neoplasms.
As seen on Slide 11, we are expanding our multiple myeloma franchise with an important ongoing Phase 3 trial that is evaluating selinexor at the low dose of 40 milligrams in combination with a well established backbone therapy of pomalidomide and dexamethasone.
Patients with relapsed refractory multiple myeloma, who have received an anti-CD38 antibody as their most recent therapy are randomized one-to-one to the oral regimen of selinexor, pomalidomide and dexamethasone or elotuzumab, pomalidomide and dexamethasone. The primary endpoint is progression-free survival.
The potential approval of this combination could lead to the only all oral potentially T-cell sparing regimen for patients with relapsed refractory multiple myeloma.
On Slide 13, advanced and recurrent endometrial cancer is the most common form of gynecologic cancer in the United States, with the current treatment landscape primarily consisting of first line chemotherapy with the platinum and taxane. Upon completion of chemotherapy, patients are observed until disease progression.
This approach clearly needs improvement given that the 5-year survival rate in this patient population is only 17%.
As selinexor is administered orally and maintenance therapy is well established in other cancer types, we believe selinexor has the potential to offer a maintenance option in TP53 wild-type patients and meaningfully improve the overall clinical benefits for these patients.
As seen on Slide 14, endometrial cancer treatment will ultimately be based upon patient’s individual molecular classification, including assessment of their microsatellite instability and T53 status.
Of the approximately 16,000 patients diagnosed with advanced or recurrent endometrial cancer in the United States, roughly 50% of advanced or recurrent tumors are classified as TP53 wild-type. Within the subgroup, 70% of patients are microsatellite stable or MSS and 30% are microsatellite unstable, or MSI high.
The long-term follow-up data observed from the pre-specified exploratory TP53 wild-type subgroup analysis from the SIENDO trial, which evaluated selinexor as a maintenance therapy reinforces our rationale and ongoing confidence in the current Phase 3 EC-042 trial.
Long-term follow up data from the SIENDO trial recently presented at the virtual ASCO plenary series on July 25 is seen on Slide 15 with a median follow-up of 25 months for the TP53 wild-type exploratory subgroup. The median PFS for the selinexor arm is now 27.4 months compared to 5.2 months in those patients receiving placebo.
The hazard ratio for the subgroup is 0.42, representing a 58% decrease in the risk of disease progression or death. Patients whose tumors are either TP53 mutant or aberrant and treated with selinexor demonstrated the median PFS of only 4.2 months.
These data show that the potential clinical benefit achieved with selinexor is isolated to women whose tumors are TP53 wild-type and demonstrate that TP-53 wild type has the potential to be a robust biomarker.
As we turn to Slide 16, patients with TP53 wild-type endometrial cancer were further classified by microsatellite instability status, given the growing importance of this diagnostic marker in endometrial cancer.
While potential PFS improvements were seen regardless of microsatellite instability status, most notable is the signal of a 68% decrease in the risk of disease progression or death corresponding to a hazard ratio of 0.32 and immediate PFS that has not been reached in those patients whose disease is P53 wild-type and MSS.
These data are important given the evolving data observed from the checkpoint inhibitors which continue to show that the greatest clinical benefit is observed in the minority of patients whose disease is MSI-high. As seen on Slide 17, we believe that the AE profile of selinexor is generally manageable as a maintenance therapy.
The most common treatment emergent adverse events seen in the TP53 wild-type exploratory subgroup were nausea, vomiting and diarrhea. And overall Grade 3/4 treatment emergent adverse events were rare, with the most common being neutropenia, nausea and thrombocytopenia. No Grade 5 treatment emergent adverse events were observed.
Treatment emergent adverse events incidence in severity were generally similar in the subgroup of patients whose tumors are either TP53 mutant or aberrant. Turning to Slide 18, given the data we observed in the exploratory subgroup of TP53.
wild-type endometrial cancer, we see an opportunity to transform the treatment paradigm for endometrial cancer given the signal of approximately fivefold increase in the time to disease progression or death compared to placebo.
The data in the P53 wild type MSS is especially notable in light of first line endometrial cancer trials evaluating the efficacy of checkpoint inhibitors.
While some of those trials evaluated the efficacy of checkpoint inhibitors in both the treatment and maintenance settings, they demonstrate that the overwhelming benefit is largely observed in those patients whose disease is MSI high.
Given that 70% of patients whose disease with MSF do not achieve the same degree of benefit with these immunotherapies.
And in light of the recent approval of Dostarlimab, in combination with chemotherapy and first one endometrial cancer, whose disease is MSI high, we anticipate that the majority of solid XOR will be administered to patients classified as P53 wild-type MSS. Pending the successful approval of selinexor.
This highlights the importance of molecular testing early in a woman’s endometrial cancer diagnosis as novel therapies transformed treatment opportunities for these women.
On Slide 19 are details in our actively enrolling EC-042 two pivotal Phase 3 study evaluating selinexor as a monotherapy for patients with TP53 wild type, advanced or recurrent endometrial cancer.
Study utilization utilizes foundation medicines tissue-based next generation sequence test to identify patients and enroll approximately 220 women whose tumors are TP53 wild-type. Patients are randomized in a one to one manner to receive either once weekly selinexor at a dose of 60 milligrams, or placebo.
Ultimately, this trial will enable the development of a companion diagnostic and we anticipate the approval of the companion diagnostic would occur at the same time as selinexor, if approved, the study’s primary endpoint its progression-free survival with the key secondary endpoint of overall survival.
The study is the collaboration between Karyopharm and ENGOT, the European Network for Gynecological Oncological Trial Group and GOG, the Gynecology Oncology Group. Given that this is an event driven trial, we currently anticipate top line data readout in late 24 to early 2025.
Turning our attention now to myelofibrosis on Slide 21, we are excited to announce that the FDA has recently granted fast track designation to selinexor to the treatment of patients with myelofibrosis.
This designation emphasizes the high unmet need for new therapies and novel mechanisms of action given that the efficacy with the current standard of care is limited, with less than 50% of patients achieving SVR35 and TSS50.
Furthermore, in subgroups such as men and those who start on a low dose of Ruxolitinib, efficacy is even lower with only approximately 25% of patients achieving an SVR35 at week 24.
On Slide 22, you can see the Phase 1 trial design of our frontline myelofibrosis study, evaluating the combination of selinexor and ruxolitinib in patients with treatment-naive myelofibrosis. We presented updated Phase 1 data at the ASCO and EHA conferences in June 2023 which can be seen on Slide 23.
In the table, you can see that the SVR35 and TSS50 results 60 milligrams selinexor. In the ITT population, the SVR35 rate at week 24 achieved with the low dose of selinexor was 79%. Furthermore, these reductions occurred rapidly with the 71% SVR35 rate observed at week 12. At week 24 TSS50 was observed in 58% of patients.
Here as well you see rapid improvement symptoms, with approximately 67% of patients achieving a TSS50 as early as week 12. The rapid deep and sustained efficacy observed with selinexor or in combination with Ruxolitinib substantially improved the potential benefit that JAK-naive myelofibrosis patients may achieve.
These data underscore our conviction on our ongoing Phase 3 study as seen on Slide 24 that was initiated in June, the trial will enroll 306 symptomatic intermediate and high risk JAK naive myelofibrosis patients. Patients will be randomized two to one to Ruxolitinib plus selinexor or ruxolitinib plus placebo. We anticipate top line results in 2025.
Given the important subgroup data and patients who receive sub optimal doses of Ruxolitinib as presented at ASCO and EHA, we are planning to initiate a Phase 2 trial evaluating selinexor as a monotherapy and JAK naive patients with the baseline platelet count between 50 to 100,000.
This is a uniquely high unmet need patient population with limited treatment options available. This trial will allow investigators to add on ruxolitinib or pacritinib at either week 12 or week 24 in the event suboptimal responses to selinexor are observed.
This trial coupled with the ongoing Phase 3 has the potential to transform treatment of myelofibrosis patients and embed selinexor as a backbone therapy for treatment naive myelofibrosis. With that, please turn to Slide 25. And I will now hand it over to Sohanya for a review of our commercial performance for the quarter..
Thank you, Reshma and good morning everyone. On Slide 26, I am pleased to present the progress we have made in our second quarter performance were XPOVIO continue to show growth year-over-year in total demand of 9% in a competitive marketplace.
In-line with our strategy to expand use of XPOVIO in the community setting, total demand grew by 11% year-over-year in this setting, contributing to about two-thirds of XPOVIOs revenues in the second quarter. We also achieve total demand growth of 6% year-over-year in the academic setting, driven by use of XPOVIO pre and post T-cell therapies.
Net revenue continue to be adversely impacted by higher utilization of carry forward our Patient Assistance Program or PAP, which provides free medicine to qualified patients unable to get financial support elsewhere.
This was a result of continued closures beginning late Q1 of many of the third-party multiple myeloma foundations that provide financial support to Medicare patients. In the second quarter, one of the four main multiple myeloma foundations was open for a period of time and continues to remain open.
This allowed for a reduction of new patients entering our patients Assistance Program. Although we continue to see the cumulative refill impact of patients who are already in path earlier in the year, PAP contributed to 14% of total demand in Q2 2023, which amounted to a roughly $3 million revenue impact.
In comparison, PAP contribution to total demand was 9% in Q1 2023 and 5% in Q2 2022.
Moving forward in 2024 IRA related changes in the design of Medicare Part D will eliminate the patient burden of the 5% beneficiary coinsurance requirements, and we expect significantly less need for Medicare Part D patients to utilize carry forward for copay assistance.
Additionally, net revenue was impacted by 5% higher year-over-year gross to net in the second quarter, driven by increased Medicare and Medicaid rebates as well as 340B discounts. Despite headwinds in the marketplace, we are pleased to see the progress we have made not only in growing total demand for XPOVIO, but also in shifting into earlier lines.
In Q2 2023, XPOVIO new patients share surpassed 60% in the second to fourth line, compared to 49% in Q2 of last year. Our intent to prescribe data showed an improvement in third line use which continues to support the potential for patients to have a more optimal experience in earlier lines and extend time on therapy. We reaffirm our U.S.
XPOVIO net revenue guidance of $110 million to $125 million in 2023. Let’s now turn to Slide 27. Amidst an evolving landscape, we believe were strongly positioned to treat multiple myeloma as a novel class of therapy in the second to fourth line in three distinct patient populations.
In the community setting where early line patients tend to be treated. We believe XPOVIO is an optimal therapy in the second to fourth line post anti-CD38 treatments as a novel class of therapy that is an effective, manageable, easily combinable and a convenient oral therapy.
It also has the advantage of decreasing the logistical burden of accessing a hospital for elderly or rurally based patients. In the academic setting XPOVIO may be used as an optimal therapy with a novel mechanism of action pre or post T-cell therapies. As we turn to Slide 28, we’re encouraged by the future growth potential of our myeloma franchise.
In our SPd study, the triplet combination of Selinexor at the lower dose of 40 milligrams with pomalidomide and dexamethasone could lead to the only all oral regimen following an anti-CD38 therapy in the marketplace if approved.
The partner backbone of pomalidomide is a commonly used therapy in the second to fourth line, generating over $2 billion in revenues in the U.S. Given these characteristics that make up the SPd combination, we’re encouraged by the potential of unlocking significant value to patients with multiple myeloma if approved.
Shifting to the opportunity in endometrial cancer on Slide 29. We are encouraged by the potential selinexor to address a significant unmet need in key molecular subgroups. As we engage with key opinion leaders in this space, it is clear that they see the augment need for targeted treatment in unique molecular subgroups including TP53 wild-type tumors.
While frontline treatment options are emerging rapidly, a clear unmet need remains in the P53 wild-type and specifically, MSS subgroup. As we look at the potential opportunity in this large market endometrial cancer is the most commonly – common gynecological cancer in the U.S., with over 8,000 patients in the U.S.
and over 50,000 globally that have P53 wild-type advanced or recurrent endometrial cancer, of which about 70% are P53 wild-type MSS patients. We are very encouraged by Selinexor is opportunity to help women who need a more effective, targeted and safe treatment option.
Given that Selinexor is being evaluated as a maintenance therapy convenience is a critical factor. As an oral therapy we maximize treatment duration by eliminating the need for frequent clinic visits. Turning now to Slide 30. As you heard from Reshma XPO1 inhibition has the opportunity to transform the frontline treatment paradigm in myelofibrosis.
There are no other drug classes other than JAK inhibitors approved in the front line. As we look at the potential opportunity in the myelofibrosis market, there are over 4,000 patients in the U.S. and over 26,000 patients globally that are intermediate to high-risk myelofibrosis.
We are very encouraged by selinexor opportunity to transform myelofibrosis treatment paradigm. Based on third-party market research, about 75% of healthcare providers were willing to adopt combination therapies as frontline standard of care, replacing Ruxolitinib monotherapy, due to the potential of better efficacy.
Additionally, there is a strong perception around selinexor in combination with Ruxolitinib, with approximately 50% of healthcare providers indicating that they would select selinexor plus Ruxolitinib as their preferred frontline combination therapy if approved, based on promising initial SVR35 and TSS50 efficacy rates and a manageable safety profile.
As Richard discussed in his opening remarks, Karyopharm has a tremendous opportunity for growth by leveraging our strong commercial team and continuing to build on our base multiple myeloma business with key potential launches ahead of us. Please advance now to Slide 31. And I’ll turn the call over to Mike..
Thank you, Sohanya. Looking at Slide 32, we have further optimized our cost structure to focus resources on our pivotal Phase 3 trials and reduced our workforce by approximately 20% including contractors.
These steps further strengthen our financial position to invest in our three ongoing Phase 3 studies, with each representing a large addressable market with unmet patient needs. Finally, as Richard mentioned, we have a capital needed to deliver on our three Phase 3 studies and maximize value for shareholders.
Now on Slide 33, I will focus on the quarter’s financial highlights. Total revenue for the second quarter of 2023 was $37.6 million, compared to $39.7 million for the second quarter of 2022. Net product revenue from U.S. commercial sales of XPOVIO for the second quarter of 2023 was $28.5 million compared to $29 million for the second quarter of 2022.
So Sohanya discussed net product revenue continued to be adversely affected by more patients using our patient assistance program, as well as higher growth to net discounts. Gross to net discounts were 22% in the second quarter of 2023 as compared to 70% in the second quarter of 2022. Turning to costs.
With our continued focus on cost management, we are pleased to be delivering a combined 12% year-over-year reduction in our R&D and SG&A expenses in the first half of 2023.
As we recognize the cost benefits from our previous efforts to focus our pipeline, our R&D expenses for the second quarter of 2023 were $31.5 million, down 28% compared to $44.3 million for the second quarter of 2022.
Likewise, we have reduced SG&A expenses in the second quarter of 2023 by 7% have $34.5 million compared to $37.3 million for the second quarter of 2022. Cash, cash equivalents, restricted cash and investments as of June 30, 2023, totaled $237.7 million compared to $279.7 million as of December 31, 2022.
Based on our current operating plants, we are reaffirming revenue guidance for the full year of 2023, as follows, total revenue in the range of $145 million to $160 million, XPOVIO net U.S. product revenue of $110 million to $125 million. With our cost reduction initiatives, we are lowering our expense guidance for 2023.
We now anticipate non-GAAP R&D and SG&A expenses, which excludes stock based compensation expense to be in the range of $240 million to $255 million for the full year 2023, down from our initial guidance of $260 million to $280 million in February.
And finally coming to our cash guidance, we have entered into an amendment to our revenue interest financing agreement with affiliates of healthcare royalty partners, extending our aggregate payment amount date by six months from December 31, 2024 to June 30, 2025 and increasing the payment cap amount from 1.85 to 1.95.
Taken together, our existing cash, cash equivalents and investments as well as the revenue we expect to generate from XPOVIO product sales and other license revenues will be sufficient to fund our planned operations through the end of 2025 excluding the maturity of our convertible bonds in October 2025.
I will now turn to Slide 34, and Richard for some final thoughts, Richard?.
Thank you, Mike. Turning to slide 35, as we have discussed today, we are rapidly advancing our pipeline, concentrating our investments in three Phase 3 programs that are expected to read out through 2024 and 2025, as we work to create near and long-term value for all our stakeholders.
I would like to thank our teams who continue to execute in a disciplined manner, and who strive each day for patients with high-unmet needs. Thank you again for joining us today. And I would now like to ask the operator to open the call up to the Q&A portion of today’s call.
Operator?.
[Operator Instructions] Our first question comes from Peter Lawson from Barclays. Please go ahead..
Good morning. And this is Shay [ph] on for Peter. Thanks for taking my question. So, first just wanted to get maybe a little more color around free drug through the PAP program.
I believe this is also an impact in 1Q, so just any color you can provide around how this is compared to 1Q and how you see this dynamic playing out for the remainder of 2023? Thank you..
Thanks Shay. Maybe for that I will turn to Sohanya to kind of weigh out how the patient assistance program and free drug has evolved from Q1 to Q2.
Sohanya?.
Hey, thanks for the question. So, in terms of the foundations in Q2, one of the four main multiple myeloma foundations was open for a period of time in Q2 which helped to allow for a reduction in patient new starts entering path, but we saw continued refill impact in PAP. So, PAP contribution in Q2 to total demand was 14% compared with in Q1 was 9%.
If you compare it with Q2 of last year at historic normals, it was 5%. So, the total net revenue impact from PAP loss alone due to foundation closures in Q2 was roughly $3 million. As we think about Q3 and Q4.
Currently, the one foundation that was partly open in Q2 continues to remain open to-date, that we have no line of sight or control into how these funds are disseminated, but our guidance range does incorporate several factors like GT and impact, but also largely this uncertainty around the path impact due to foundation closures..
Great. Thank you. And maybe just a final quick question is around some of the cost refinements. So, I know there is a workforce reduction this quarter.
Is there anything the team have been thinking about in terms of whether there may be program refinements kind of later in the year, any kinds of cost cuttings that we should be thinking about?.
Yes. Thanks Shay. I think as we have highlighted, we continue on an ongoing basis to make sure we are going to optimizing and focusing our cost structure.
So, we have continued to do that with the approximately 20% reduction in our workforce this quarter to really ensure we are focused on being able to deliver our three Phase 3 programs with our investments obviously in multiple myeloma, endometrial cancer and myelofibrosis.
And on an ongoing basis, obviously we continue to evaluate our costs to ensure we are really being diligent in our – allocating our capital..
Okay. Thank you..
Our next question comes from Maury Raycroft from Jefferies. Please go ahead..
Hi, this is Kevin on for Maury. Thanks for taking my questions. Just for endometrial, could you say whether the shift in timeline there for the readout? Was that due to competition with PD-1s.
And then also could you talk about the powering for this study and whether you will look at the MSS and MSI high patients as pre-specified subgroups within that TP53 wild-type patient population. Thanks..
Thanks Kevin. I will turn to Reshma to kind of put all that together and talk about the focus and the progress in endometrial cancer as we advance our EC-042 trial..
Hi Kevin, this is Reshma. So, thanks for the question. In terms of the timelines, there is a slight modification from end of late 2024, beginning of 2025. Of course, this is an event driven trial. So, when we see the events actually occur that will trigger our ability to perform the analysis for progression free survival.
With that said, we are closely looking at how the data is positively evolving in this most recent update that brain tumor, it’s presented at the ASCO plenary. We now see the median PFS in those TP53 wild-type patients evolved from the 13.7 months that we initially disclosed back in the beginning of last year to now 27.4 months.
So, more than a doubling in that median PFS, that is going to have a slight impact on how fast those events accrue taking that into account we have re-projected and anticipate again those PFS events to occur either late 2024 or beginning of 2025. We are probably looking at approximately a couple of months spread.
In terms of looking at the at the P53 wild-type MSS, it’s a great question. Obviously, the data are very encouraging.
And that subgroup which does comprise the vast majority of all patients, the way that the EC-042 trial, the Phase 3 is designed, it’s specifically focused on that P53 wild-type subgroup regardless of whether MSS, MSI and largely because this is a novel subgroup.
And again, we believe that the data specifically observed in that P53 wild-types subgroups truly is unprecedented. Of course, we will be looking at the subgroup of patients who are P53 wild-type MSS and separately P53 wild-type MSI, but right now our focus truly is on that large P53 wild-type subgroup or patient population, I should say..
Great. Thanks. That makes a lot of sense. And then just to follow-up on myelofibrosis. We saw that one of your competitors recently top line data, Phase 3 data showing they hit stats big on spleen size but not symptom score. There is also another update expected this fall.
Could you just talk about how you view the evolving treatment landscape here? And then what gives you confidence that you will be able to succeed on the symptom score co primary in your Phase 3. Thanks..
Yes. So, I saw that press release too, I am not providing any additional data beyond what you saw as well. What I found very intriguing is actually how that ruxolitinib arm performed.
It was actually an SVR rate of approximately 30%, right, which is a little surprising to me lower than what the data that was presented in the COMFORT trial analyzed more than 10 years ago.
It really suggests to me that the benefit that ruxolitinib is having on that important screen volume reduction probably lower than what we expected, but I look at our data from the Phase 1 trials, specifically assessing selinexor 60 milligrams in combination with ruxolitinib. My confidence goes up, given the fact that we saw 78%.
So, that 78% compared to that 30% ish really suggests that we can have a very meaningful benefit on screen volume reduction in our ongoing Phase 3 study. In terms of the TSS50 that to a certain degree, I am not that surprised. So, my understanding from the earlier transform Phase 2 trials is that their TSS50 was marginal at best.
Now, why is it marginal, hard to say, right. We know that a lot of aspects can contribute to TSS50 scores including toxicity as well as patients not completing out their form so missingness in that data. Obviously, we continue to analyze their data and hopefully report on more mature data later this year, maybe even beginning of next year.
I go back to our data in which we had an opportunity to look at the TSS50 data obtained from the patients enrolled as part of that Phase 1. And I am again very encouraged by the 58% TSS data that we saw.
Again, compared to ruxolitinib which TSS50s are in the low-40s, it really does suggest that the combination of selinexor plus ruxolitinib can meaningfully improve both SVR and TSS50 both important endpoints that we need to hit as part of our Phase 3 trial..
Great. Thank you very much Reshma..
Our next question comes from Colleen Kusy from Baird. Please go ahead..
Great. Thanks. Good morning and thanks for taking your questions. So, in the SIENDO presentation from the ASCO plenary, you continue to see an increase in PFS versus placebo.
Can you share what the average time on therapy has been just trying to think about that in context of the market opportunity for duration and endometrial cancer?.
Yes. Appreciate the question, Colleen. So, we haven’t reported on that median duration of treatment yet. And it’s only because those data are still maturing, we actually still have patients on treatment.
And as the data continue to mature, we will have an opportunity to present that median duration of treatment, likely at an upcoming presentation in the next 6 months to 12 months. We do know that median duration of treatment and PFS don’t track one-to-one. However, we are seeing interesting trends.
So, as median PFS gets longer, we are also seeing that median duration of treatment also get longer. So, I think that is a very meaningful evolution both from a progression free survival, but time on therapy as well..
That’s helpful. Thank you. And then congrats on getting the Phase 3 myelofibrosis study up and running and the fast track status there.
I know it’s early, but how challenging is it to find naïve myelofibrosis patients? And how many centers do you think you would target for this study?.
Yes. So, yes, very important milestone to get that Phase 3 initiated. We have got a lot of momentum behind this trial, right. And I think again many of our investigators are very encouraged by the aggregate data that we have been able to present from that Phase 1 trial evaluating selinexor in combination with ruxolitinib.
Again, not only the spleen volume reduction and TSS50, but those key aspects that really suggest that the combination is having a positive disease modification and this potential monotherapy. So, it’s this holistic profile that really suggests that this combination can be a game changer for patients who are treatment naïve myelofibrosis.
In terms of competition, well, there is none, right. So, there is no other large Phase 3 trials. By and large, this is going to be a global trial. We are activating sites in the U.S., Europe, as well as Asia. We are looking at approximately 150 sites.
And again there is really no competition for those treatment naïve myelofibrosis patients that are diagnosed throughout the globe. So, we are encouraged by the enthusiasm, the lack of competitive headwinds. And just really strong support from all of our investigators..
That’s great. Thanks.
And last one from us on the monotherapy myelofibrosis study, you talked about in the call, can you share about the rationale and why you picked that patient population to look at?.
Yes. So, this was a really innovative trial design for us. And it’s largely based upon this really intriguing finding, we have seen from the Phase 1 study specifically in that subgroup of patients who were treated with suboptimal doses of ruxolitinib. We are finding that patients are still achieving that important SVR35 and TSS50.
Again, you don’t see that with ruxolitinib alone, really suggest that XPO1 is a fundamental mechanism. And so XPO [ph] potentially has monotherapy activity. So, this trial allows us to better investigate that hypothesis.
How this trial is going to be conducted is that patients who are treatment naïve myelofibrosis and specifically who have baseline platelet counts of 50,000 to 100,000 are going to be treated with selinexor monotherapy at either the 60 milligram or 40 milligram doses.
And then in the event date, they achieve a suboptimal response to selinexor, they have an opportunity to add on either ibrutinib [ph] or ruxolitinib. Why are we looking at this patient population because we know that patients whose baseline platelet counts are between 50 and 100 really have very limited treatment options.
By and large, the only therapies available to them are going to be ibrutinib and ruxolitinib. Despite these therapies, their SVR and TSS50 with these therapies are still quite marginal. So, it’s an opportunity to assess selinexor monotherapy and potential these novel combinations to..
Great. Thanks for taking our questions..
In the interest of time, please limit yourself to one question. And our next question comes from Chris Raymond from Piper Sandler. Please go ahead..
Hi. Good morning. This is Nicole Gabreski on for Chris. Thanks for taking the questions. So, maybe just around overall survival and endometrial, so I know that was a secondary endpoint and the trial and kind of came up with a topic of discussion during the ASCO plenary session.
So, I was just wondering if we should expect you to disclose any OS data from the trial in the future. And then just quickly for eltanexor.
I know you guys are focused on your late stage programs, but just wondering how you are thinking about the path forward for ultimate MDS at this point and maybe just how we should think about the prioritization of that program..
Thanks Nicole. Well, I think as Richard was indicating over the next 6 months to 12 months, as we continue to see the majority of the data in the endometrial cancer, see handled trial we will report out on the OS.
And maybe I will turn to Reshma to kind of talk about eltanexor, which obviously is very important for us as we continue to move forward and looking at potential benefit, we can bring patients.
Reshma?.
Yes. Thanks Nicole. So, eltanexor is one of our four core programs specifically evaluating myelodysplastic syndromes, neoplasms, specifically relapsed refractory MDS with eltanexor.
Very encouraged by the data that we reported from the Phase 2 will have an opportunity in the next few months to really define that optimal development plan specifically with eltanexor in this high risk patient population..
Okay. Thank you..
The next question comes from Brian Abrams from RBC Capital Markets. Please go ahead..
Good morning. This is Joe on for Brian. Thanks for taking our question. With the fall of data at ASCO, just going back to the endometrial cancer, the full data continued to seem very encouraging. And I know you just mentioned that some patients continue to remain on therapy and continue to show up PFS benefits there too.
So, just wondering if there is any expedited pathway for approval. And before the top line reads out in early ‘24 or early ‘25, or is it something that you have discussed with the FDA so far? Thank you..
Yes. Thanks Joe. So, we don’t comment on our interactions with the FDA. With that said EC-042 remains our opportunity to get both selinexor the drug as well as the companion diagnostic in the form of the NGS platform in which we assess P53. As our approval opportunity in the U.S. as well as ex-U.S. to EC-042 is a well designed trial.
In that we are prospectively evaluating patients who are P53 wild-type. It’s a well powered study that will specifically allows us to assess that important progression free survival and overall survival compared to placebo. So, we remain focused on that EC-042 trial that is really evolving quite nicely.
SIENDO, though and the data that we have observed from SIENDO, very much is informing our – informed our design of that trial. We remain encouraged those data only increase our confidence in the likely outcome from ECO42..
Our next question comes from Eric Joseph from JPMorgan. Please go ahead..
Hi, this is Noah on for Eric, thanks for taking our question. In regards to ECO42 study, what median PFS in the placebo arm is anticipated, for that you are powering assumptions.
In your guidance for the readout, is it similar or more generous than that of the P53 wild-type group…?.
Yes, so great question. So, we haven’t disclosed on those kinds of details. With that said, we are assuming a median PFS for selinexor or exceeding that 13.7 months, right. So, those were the data that we observed at the time of the initial data cut again in the beginning of 2022.
Given the fact that median PFS continues to increase quite nicely, again we are quite confident that that median PFS is going to be in the excess of 13.7 months. It is all of our Phase 3 trials are well powered, well above that 80%.
So again, very confident that at the time that we are able to read out the PFS anticipated end of ‘24, beginning of ‘25, we are going to see a very meaningful improvement in that PSS with the selinexor treated patients compared to placebo. Thank you..
Got it. Thank you..
And the next question comes from Jonathan Chang from Leerink Partners. Please go ahead. .
Hey, guys, this Mike Todd for Jonathan. Thanks for taking my question. You mentioned some enthusiasm around the [indiscernible] and treatment naïve modified versus and the data are certainly impressive.
I was just wondering with the upcoming combination readouts and potential approvals there how does that impact the development and regulatory interactions for your trial? Given it’s only against rux monotherapy? Thanks..
We don’t really anticipate any kind of impact with either the data readouts, right. Data read outs are just the top line results. Obviously, the companies need to go through the extensive regulatory process. We anticipate, our trials to be enrolled or almost close to enrollment. Completion enrollment by the time that regulatory approval is obtained.
Again, assuming that those data are positive for both SVR and TSS50. So again, we are very confident not only in the data, but in the design of our Phase 3 trial..
Got it. Thank you so much for taking the questions..
This concludes our question-and-answer session. I would like to turn the conference back over to Richard Paulson for any closing remarks..
Thank you operator and thank you everyone for joining our call today. As I indicated at the beginning of the call, we had a very strong second quarter, as we continue to accelerate Karyopharm to its next stage of growth with our novel sign compounds both selinexor and eltanexor.
And once again, I would like to thank our teams who execute in a very disciplined manner, striving each day for patients with high unmet needs. And thank you everyone for joining the call today..
The conference has now concluded. Thank you for attending today’s presentation. You may now disconnect..