Good morning. My name is Jason, and I will be your conference operator for today. At this time, I’d like to welcome everyone to Karyopharm Therapeutics' First Quarter 2021 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.

Great. Thank you. And thank you all for joining us on today's conference call to discuss Karyopharm's first quarter financial results and business update. And let me be the first one to officially welcome our President and Chief Executive Officer, Mr. Richard Paulson, to our quarterly earnings call. This is Ian Karp, and today in addition to both Michael Kauffman and Richard Paulson, I am also joined by Mr. Mike Mason, our Chief Financial Officer; Mr. John Demaree, Chief Commercial Officer; and Mr. Stephen Mitchener, Chief Business Officer. On the call today, Michael will provide an overview of key recent corporate developments and an update on our commercial progress, followed by an update on one of our key pipeline opportunities in endometrial cancer. Mike Mason will then provide an overview of the first quarter financial results. We will conclude with some thoughts from Richard on Karyopharm's future, and then we’ll move to the Q&A portion of the call.

Thank you, Ian. And good morning, everyone. Let me begin first by saying how thrilled I am to also be joined here today with Richard Paulson, our company's new CEO. And we'll begin on slide four. Dr. Sharon Shacham and I started Karyopharm over 12 years ago. Our mission was really quite simple. We wanted to do everything we could to make a difference in the lives of patients battling cancer. More specifically, we sought to develop novel drugs that exploited a fundamental pillar of oncogenesis, namely, the reactivation of tumor suppressor proteins by inhibiting their export out of the cell nucleus, which as you may know, is actually where the name Karyopharm comes from. Now, with our lead medicine XPOVIO having received three separate FDA approvals and one marketing authorization in Europe, over 450 employees, and a robust pipeline of programs across both immunologic and solid tumor indications, I could not be more proud of the work we've accomplished on behalf of patients, their families, and healthcare providers. But as our company is increasingly focused on commercial execution and competing in the global cancer marketplace, the time is right for a new leader, particularly one with a strong track record of building successful oncology commercial brands. Richard, of course, is no stranger to Karyopharm, as he served on our Board of Directors since February 2020. Prior to his new role here, Richard served as Chief Executive Officer of Ipsen North America and is the former Vice President and General Manager of Oncology at Amgen. Richard will provide some of his thoughts regarding Karyopharm's future at the end of today’s review of our Q1 2021 earnings and business update. Please now turn to slide five. Total revenues were $23.3 million, with XPOVIO net product sales of $21.7 million in the quarter. Importantly, exposure prescription demand increased 17% in Q1 2021, as compared to Q4 2020, following the expanded FDA indication granted in December 2020. We also saw more than 160 new physicians or accounts prescribing XPOVIO for the first time in the quarter. This quarterly growth occurred when many myeloma brands were flat or declining. Moving to our pipeline progress, we recently announced that in March 2021, the European Commission granted Conditional Marketing Authorization for NEXPOVIO in combination with dexamethasone for the treatment of patients with multiple myeloma who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, two immunomodulatory agents, and an anti-CD38 monoclonal antibody, and who have demonstrated disease progression on the last therapy.

Thank you, Michael. Since we issued a press release earlier today with the full financial results, I will just focus on the highlights which began on slide 15. Net product revenue for the first quarter of 2021 was $21.7 million, compared to $16.1 million for the first quarter of 2020. The estimated gross to net discount for XPOVIO in Q1 2021 was slightly higher at 21%, in the top of our expected range of 15% to 20%. License and other revenue for the first quarter of 2021 was $1.5 million, compared to $2.1 million for the first quarter of 2020. R&D expenses for the first quarter of 2021 were $37.1 million, compared to $34 million for the first quarter of 2020. The increase in R&D expenses in 2021 compared to 2020 was primarily attributable to costs incurred related to our ongoing clinical trials and regulatory activities. Selling, general and administrative expense for the first quarter of 2021 was $37.7 million, compared to $30.7 million for the first quarter of 2020. The increase in SG&A expenses compared to the prior year was due primarily to activities to support the U.S. commercialization of XPOVIO. On slide 16, you can see cash, cash equivalents, restricted cash, and investments as of March 31, 2021, totaled $233.6 million, compared to $276.7 million as of December 31, 2020. Finally, based on our current operating plans, Karyopharm expects non-GAAP R&D and SG&A expenses, which exclude stock-based compensation expense for the full-year 2021 to be in the range of $280 million to $300 million. The company expects that existing cash, cash equivalents, investments, and the revenue it expects to generate from XPOVIO product sales and other license revenues will be sufficient to fund its planned operations into late 2022. We are not providing revenue guidance for 2021 today, as we remain in the initial launch phase of XPOVIO and its expanded indication, but do expect to see meaningful growth in 2021 relative to 2020 with the ramp of sales increasing in the second half of the year, as we expect to see the benefit of a longer duration treatment for multiple myeloma patients being prescribed XPOVIO earlier in their treatment course and/or in combination with Velcade. I'll now turn the call over to Richard for some of his thoughts about Karyopharm’s future. Richard?

Thank you, Mike. Let me begin by saying how excited I am to be leading the Karyopharm organization in such inspiring times. Of course, Karyopharm is not new to me, as I have served on its Board of Directors since February 2020. First, I would like to acknowledge and thank Dr. Michael Kauffman for his immense contributions to the scientific and initial commercial success achieved by Karyopharm. Dr. Kauffman, both as a clinician and drug developer, has truly enabled our company to reach amazing scientific and clinical achievements. During my tenure on the Board, I've been extraordinarily impressed with what this amazing company has been able to do in such a short period of time. Now with three separate FDA approvals and one conditional European marketing authorization grant, all having been achieved in just the past few years. Of course, all of these approvals were preceded by many years of careful and thoughtful clinical development for XPOVIO. Karyopharm remains deeply rooted in innovative science, with a passion for improving the lives of patients battling cancer, something that is very near and dear to me as a passion I work towards. Importantly, I believe the best is yet to come for both Karyopharm and for the patients we aim to serve. However, I know that a lot of work still remains. As Karyopharm has now effectively transitioned to a commercial stage organization, I am excited to lead the company and its next chapter, as we seek to expand XPOVIO’s impact across indications and geographies. I look forward to leveraging my experience in global product commercialization and organizational leadership to help further advance Karyopharm’s impact in helping improve patient outcomes. I'm excited to work alongside both Michael and Sharon, on behalf of our patients, employees, partners and shareholders. Regarding my initial priorities, in the near term, I think we have a great opportunity to expand our breadth and depth in the multiple myeloma treatment landscape, where we have really just begun to scratch the surface regarding where we can compete and help patients. As we continue to generate additional combination data with other myeloma drugs, we believe XPOVIO has the opportunity to become an increasingly important backbone therapy. Moving beyond multiple myeloma, I believe XPOVIO can become a portfolio in a pill with the potential to have clinically meaningful utility across a host of cancers, including many solid tumor indications, both as a single agent and importantly, as a future combination partner of choice with other cancer medicines, allowing for synergistic opportunities to further help patients battling cancer. Before we open the call to your questions, let me highlight a few of the key commercial, clinical, and regulatory milestones that we've already achieved so far in 2021, and others that we expect for the remainder of the year and shown on slide 17. We have made significant progress in Europe, where we recently received Conditional Marketing Authorization for NEXPOVIO and have submitted a Type II Variation application based on the Phase 3 BOSTON study, which was recently validated by the EMA. While we have made some progress increasing XPOVIO sales in the U.S., we are far from content and remain committed to further penetrating the U.S. market throughout the remainder of this year and beyond. This is where I intend to spend much of my time in the weeks and months ahead. Finally, in the second half of this year, we expect top line data from the Phase 3 SIENDO study in endometrial cancer, the initiation of multiple clinical trials and the presentation of additional combination data with XPOVIO and other cancer therapies at various medical meetings. I look forward to updating the investment community on our continued progress in the months and quarters ahead. With that, I would now like to ask the operator to open the call up to the question-and-answer portion of today's presentation.

Thank you. We will now begin the question-and-answer session. Our first question comes from Brian Abrahams from RBC Capital Markets. Please go ahead.

Hi there. Thanks for taking my questions. And I guess first off, congratulations to Michael and Sharon on all your accomplishments. I want to wish you the best of luck in your new roles, and congratulations to Richard as well.

Thanks, Brian.

Yeah, so first off I just - I'm curious if you could maybe provide a little bit more color around XPOVIO use patterns in the U.S. in the earlier line population. Maybe can you help characterize the blend of the penta-refractory versus earlier line BOSTON population being put on drugs based on your market research? And what's your sense as to how XPOVIO is fitting into the current competitive landscape across lines versus, you know, in previous quarters? And then had a follow-up? Thanks.

Yeah. I'll turn that to John Demaree, our Chief Commercial Officer. John?

Thanks, Michael. As the sales growth we saw, Brian, with the cross lines of therapy, with the majority coming from later line patients. It's hard to tell for sure as prescription data we received from our specialty pharmacies and distributors have not captured in what line of therapy patients are receiving XPOVIO. However, from secondary market research data we purchased, our market research with prescribers and ad-boards, our sense is that still much of the business is coming from later lines, PG fourth line and later lines. Though many of those patients are now receiving the triplet combination with XPOVIO and another myeloma backbone instead of just XPOVIO plus dexamethasone, which was more common in the past, indicating we're getting trial of the new triplet indication, and we would expect them to try it in later lines and then move it up into earlier lines as they have success. So while the majority of patients are still in later lines, we are making inroads with some physicians who are starting to prescribe XPOVIO to their second and third line patients.

Got it. That makes a lot of sense. And then maybe just as a follow up, just a bigger picture, strategic question for Richard on selinexor, obviously, as shown signals in a number of different tumor types. Where do you see the most promising opportunities for the drug? And do you see any opportunity to further refine the development strategy or even maybe partner in some of these combo indications you mentioned to split economics to enable any further cost savings on the R&D side? Thanks.

Thanks, Brian. You know, we'll get into that in the future and share with you and the other analysts. But, you know, I think in the near term, we have a great opportunity to really expand our breadth and depth in the multiple myeloma treatment landscape. As you know, we've just begun there and John talked about that as we're starting to move into earlier lines where we can compete and help our patients. As you heard from Michael, we are generating new data in the XVd study as we continue to generate additional combination data with other myeloma drugs. I do believe we have the opportunity to be a backbone in many areas. As we move forward, as we heard a little bit around SIENDO, moving beyond multiple myeloma I really believe this opportunity to be a portfolio in a pill is clinically meaningful for us and will allow us to have utility across a host of cancers. We'll have to explore moving forward how we bring that to life. We look at many solid tumor indications, both as a single agent and importantly, as you touched on as a combination partner for selinexor cancer medicines. This is going to allow us to really synergistically bring XPOVIO for more patients battling cancer moving forward.

Got it. Thanks so much.

The next question comes from Maury Raycroft from Jefferies. Please go ahead.

Morning, everyone. And I would like to add my congrats to Michael, Sharon, and Richard too. Maybe first question is just, if you can talk more about the higher gross-to-net discounts in Q1 compared to Q4 2020. Can you say what the discount was in Q1? And will this continue going forward? Or how should we think about it?

Sure. Yeah, I think - so we’ve guided that we'd end up in a range of 15% to 20% for growth, and that we ended up just slightly north of that, in Q1 at 21%. And pretty typical, you know, where the first quarter with the co-pay resets, et cetera. We do expect that to come down into our range of 15% to 20% for the entire year, with some lumpiness quarter-to-quarter.

Got it. That's helpful. And then, as far as access for the sales team goes, can you provide any more specifics or quantify how much access they have currently, and where you aim to get in the second half of '21?

John will take that.

Yeah. In terms of access to customers, you know, COVID has been a challenge. It's created an impact for patients and HCPs in the entire industry, and we do still have some access challenges. We do see that growing. It's growing at a different pace in different parts of the country. The last secondary data report that we saw suggested that about 20% to 25% of our interactions are in person, and 75% to 85% of our interactions are still virtual. We're providing our teams tools to engage with their customers in both the virtual and in-person environments, so they continue to drive the BOSTON message as we go forward. We expect as we go throughout the remainder of the quarter and year that access in person to our customers will continue to grow substantially.

Got it. Okay. Thank you for taking my question.

Thank you.

The next question comes from Peter Lawson from Barclays. Please go ahead.

Hi. Hey, Michael, just always been a pleasure speaking with you and best of luck with next steps. And maybe the first question, just for Richard just on - as we get really transfixed on first hundred days. So just wonder if you could walk us through what you're thinking for the initial steps at Karyopharm?

Yes, thanks. Thanks, Peter. You know, in initial steps, I think over the next hundred days, I mean, really, what I'm super excited about with Karyopharm is the opportunity to help patients. You know, as you know, XPOVIO I think is uniquely positioned with its broad mechanism of action and its ability to be combined with a variety of other cancer drugs. This is going to enable us to make a tremendous impact on patients battling cancer. In the near term, our focus is to move past the initial launch of XPOVIO in penta-refractory multiple myeloma; the initial launch was successful. As we expand into earlier line settings, it's going to require us to really expand our breadth and depth. So that is a key area of focus for me in the near term. And also, should the Phase 3 SIENDO study and endometrial cancer prove successful, we will need to start on preparations early in the next little while. This is potentially a significant commercial opportunity for us moving forward, and we're going to need to see how we bring that to light over the near term. A couple of areas of my near-term focus would be in the process of discussing and evaluating potential partners in Europe and Japan, with the recent marketing authorization in the EU, as well as the acceptance of the EMA for BOSTON indication, which is where we know much of our value to us, and potential partners will be generated. We need to continue to explore those partnership opportunities.

Thank you. And then just from your prior experience, Richard, what parallels do you have with drugs similar to selinexor?

Thanks, Peter. In the past, I have had the opportunity to bring drugs to market in multiple myeloma; specifically working on Kyprolis. In many areas, when you first launch, and later on later stages of the disease, you need to continue to work with physicians to help them better understand the medicine and how to initiate and manage patients. That's a process that takes time, but one which we're committed to moving forward.

Perfect. Thanks so much. Congratulations. I’ll get back in queue…

Thank you.

The next question comes from Eric Joseph from JPMorgan. Please go ahead.

Thanks for taking the questions. Good morning. And congrats again on the role Richard, I will do my best to not call you Paul Richardson.

Thank you.

Come on…

Especially, multiple myeloma.

Right. Just a couple of questions on recent prescription trends, and looking forward here, exiting first quarter growth seems pretty strong. I guess, can you comment on demand trends through April so far? And are you able to perhaps guide us a little bit on second quarter expectations? And then just a follow up on sort of where you're seeing use right now, you note that with once weekly - sorry, with most of the demand being for the ones weekly regimen just sort of combination use. Is there any expectation that, that might kind of accrue to longer average duration on therapy? Or is it really more about trying to expand into earlier line years before we might see the benefit of you know, longer time on therapy occurring to sales? Thanks for taking the question.

Eric, it’s Michael. Listen, we're not going to comment on this quarter's growth at all at this point. We'll update you obviously when we can, but I will turn it over to John for the second part of the question.

Yeah. Looking at our dosing - thanks for your question, Eric. Just as an example, last year, in Q1 over 50% of our new patients were being started on the twice a week 80 milligram dose, or 160 milligrams per week, which was the starting dose in the STORM population. In this most recent quarter, only 15% of patients were started on that dose, with the remaining 85% being started on a once weekly dose, most commonly either 100 milligrams or 80 milligrams. While we can't be exactly sure which line of treatment these prescriptions are being generated in, syndicated market research we purchased suggests many of them are being prescribed with other multiple myeloma drugs such as Velcade from the BOSTON study, or with Pomalyst or Darzalex, which are in the NCCN guidelines or with Kyprolis, which has been studied in the STOMP trial. We continue to see the triplet use expand, most likely in the later line populations. We do expect that to move earlier as patients get more comfortable using XPOVIO with different triplet combinations. As a company, we will only promote the SVd indication, which is our own label indication.

Okay, guys. Thanks for taking the questions.

The next question comes from David Lebowitz from Morgan Stanley. Please go ahead.

Thank you very much for taking my question. Is it fair to say that the - almost all the incremental increase in prescriptions is from the expanded label? Or is there some incremental increase from the DLBCL? And maybe some additional from the initial indication?

Yeah. I think it's fair to say that the 17% demand growth was driven primarily by new patient starts in multiple myeloma, with most of that being an increase in triplet usage, so driven by the new indication that we've seen.

How do you expect, I guess, if there's any way to qualitatively estimate how the shift in the environment as patients are starting to see their doctors a little bit more actively with vaccinations going up as the year goes on? How could that number shift going forward? And how should we look at that when we model as far as what type of demand could change going forward?

I think it was interesting to see in the first quarter, when you look at all the multiple myeloma brands that have reported this quarter to date, as Michael mentioned, it seems to be a down quarter in terms of multiple myeloma. We would expect as patients are vaccinated that patients will return to see their physicians and they'll be getting new therapies. So we would expect the market to return to growth. We would expect to benefit from that market growth, as well as obviously incremental growth above that with the continued launch and success in driving uptake in earlier lines with the BOSTON indication.

Thanks for answering my questions.

Thanks for your question.

The next question comes from Jonathan Chang from SVB Leerink. Please go ahead.

Good morning, and thanks for taking my questions. First question, given it sounds like the majority of revenue currently is still coming from the later line STORM setting or the later line setting period? Can you speak to reasons for the confidence that you'll be able to successfully penetrate to earlier line settings and see that benefit a longer duration of treatment in the second half at those numbers?

Maybe I'll start, and then I’ll turn to John and Richard may have a comment. The main driver here is education of physicians. Physicians for the last five years have assembled a series of multiple different triplet therapies typically that they use in first, second, third, and fourth line settings, and they're comfortable with those. We're a new entry. While this is not the unmet medical need that we had when we went into penta-refractory, we do have one of the simplest, if not the simplest, triplet therapy in terms of administration and time required for a patient to come into clinic. What you're doing now is having to educate doctors that there's a new kid on the block, and that it's quite simple, it's easy. With the proper prophylaxis, it can be very manageable with patients on this combination for over two years now. So that's the main driver here. As John mentioned, with our salesforce getting back face-to-face, we will be able to change practice and guide physicians that there is a new option out there.

Yeah. I think Michael's point about education is critical. We're also deploying a number of new tools to help continue to reinforce and drive that education. So we're deploying interactive content that can be used in-person or via virtual engagements by both our salesforce and our marketing team. In addition, we recently made significant investments in our digital ecosystem to improve that physician education, including website enhancements, KOL videos, banner ads, search engine marketing, search engine optimization, digital media, social networking, competitive media pilots, and plan to continue to expand this substantially going forward to drive that education that Michael spoke to is being critical. We're also investing in significant peer-to-peer education via both live and digital channels. Finally, beyond just branded, we're enhancing disease state education around the role of XPO1 in addition in cancer, including in multiple myeloma. So a number of things that we're doing to continue to drive that education in the second half of the year and into the second quarter.

Got it. Thank you. And just one follow-up to that. Can you give us a sense of what you can and can't track in teasing out where these sales are coming from? Thank you.

I'll just - this is Ian. Jonathan, not much has really changed there. For those who have been following our story for some time, essentially, able to track from our distributor network, certainly, for about half of our business that goes through specialty distributors, we can see essentially just what dose of drug is being prescribed and how much per account. For the other half of our business, we're able to see a bit more data where we can see are these new patients, are they refills, and that's where we get our refill data from, and we can see it are these multiple myeloma patients or these DLBCL patients. However, this data, unfortunately, does not give us specifically what line of treatment these patients are from, and it doesn't tell us what specifically combination drugs are being prescribed.

The next question comes from Ed White from H.C. Wainwright. Please go ahead.

Good morning. And congratulations to Richard. Thank you, and congratulations to Michael and Sharon as well. So just two pipeline questions. The first is on XPORT-035 and 034 in myelofibrosis. I was just wondering if we can get a status update and perhaps when we can see data from those studies. The second question is on the solid tumor studies, and just wanted to get an update there on GBM, non-small cell lung cancer, and colorectal cancer. Any kind of updates you can give us there on status and timing to data would be appreciated as well. Thank you.

Hi, Ed. We will update on the - I know the 034 and 035 myelofibrosis studies are on clinicaltrials.gov. When we have our first patients enrolled, we will announce those as typical. We won't be able to give much in the way of data expectation, just given the accrual rates and so on and so forth. But we're quite encouraged about the underlying basis for doing those studies. Hopefully, this year, you guys will see some data in that regard. For the solid tumor studies, the same thing applies. The colorectal and lung studies are ongoing, and we hope to provide updates in medical meetings when appropriate, hopefully this year. For the GBM study, similar, although I think we've just initiated as you know, some of the new cohorts in frontline combination and in relapsed in combination with lomustine. Those will take a little bit longer, and I would expect maybe next year to see them, but we'll have to see.

The next question comes from Colleen Kusy from Baird. Please go ahead.

Hi, good morning. Thanks much for taking our questions. And congrats to the whole team. If you could comment on what the inventory stocking level is as of the end of 1Q? And then when you're thinking about competition in the later lines with multiple myeloma, as what are some of the features of XPOVIO that really resonates with the prescribers when thinking relative to competitors?

Mike Mason will discuss the inventory.

Sure. As Michael mentioned earlier on the call, we had 17% demand growth, but 7% ex-factor growth. Part of that was gross-to-net and part of the other difference is with some stocking that happened in December 2020. As you recall, we got the BOSTON approval in mid to late December, so we saw some stocking in December. We didn't see much of a benefit from that in Q1, so that led us somewhere around four weeks of inventory, which is pretty consistent with what we've had in prior quarters.

John will take the second part.

Yeah. In terms of what customers are looking for in later lines with therapy, our goal with the BOSTON data is to move into earlier lines of therapy. What we've seen there in multiple myeloma is that many physicians believe it's important to treat with different mechanisms as early as possible in the patient's course of disease. One of the key advantages XPOVIO brings is its novel mechanism of action that is synergistic with proteasome inhibitors like Velcade and the indicated XVd regimen. We also know that they're very focused on efficacy, and we're able to communicate with the XVd regimen rapid and sustained PFS benefit, as well as clinically significant durable responses, all attributes that are very important to the customers. It’s important to note that the landmark BOSTON study is the only trial out there today to study Velcade weekly, the way it's actually used by clinicians in clinical practice. Despite using that weekly dose or half the dose of other trials, we still produced very strong data for patients. These are some of the attributes that physicians are looking for, and we're highlighting as we work to move XVd into earlier lines of therapy.

Great. Thank you, it's really helpful. If I can quickly ask the follow-up, is SIENDO data positive, how much incremental investment would you expect you'll need to make in your commercial infrastructure to expand into solid tumors?

Yeah, go ahead, John.

We're actually doing that assessment right now to look at the overlap of accounts and the size of the commercial platform and footprint that we would need to fully maximize that. So that's something that we'll be able to provide more data to you at a later point.

Okay, thank you.

The next question comes from Arlinda Lee from Canaccord. Please go ahead.

Hi, guys. Thanks for taking my question. I guess, I was curious about on the education front. I'm curious what you guys are encountering as whether the disconnect is or the hurdle is for prescribers to prescribe more into the BOSTON trial, or Boston patient population? Thank you.

I'll start, and John can add. I don't think there's really a disconnect. Again, I think it has to do with doing things you're used to doing, doctors are very much - you know, they're confident with what regimens they had prior to the BOSTON approval. They've been working on them and honing them for the last five years, which is really the last time that a major second-line, new indication or new drug came out. So they're just comfortable. It's a little like, you know, before we all used seatbelts, nobody really wanted to put them on, but you eventually get used to it and then it becomes second nature. We have to make the BOSTON regimen second nature to physicians, and that's going to take a little bit of time. But I don't think there's a problem here at all. When the doctors, typically most doctors, when they use this regimen, they're pleasantly surprised when they use proper prophylaxis, we get a number of doctors calling us and saying the patient didn't have any nausea. We asked them what they did, and they said they used what you suggested and that’s how it works. We know how to prevent the side effects from this drug; a lot of them are reversible, and we just have to change people's habits.

Michael is absolutely right. Some physicians have that habit based on the STORM data. As you know, that once weekly dosing regimen in the BOSTON is better tolerated and shows a higher level of efficacy. Just getting physicians to try that new regimen versus the original regimen we launched with is critical, and we continue that education process.

There are no more questions in the queue. This concludes our question-and-answer session. I'd like to turn the conference back over to Richard Paulson for any closing remarks.

I'd like to thank everybody again for joining today's call and we look forward to updating you on our progress as soon as we can. Thank you, operator. We’ll close the call.

The conference has now concluded. Thank you for attending today's presentation. You may now disconnect.