Jasper Therapeutics, Inc. (JSPR) Earnings Call Transcript & Summary

Thank you for standing by. Welcome to the Jasper Therapeutics Chronic Urticaria Data Update Webinar. [Operator Instructions] As a reminder, this call is being recorded, and a replay will be made available on the Jasper Investor Relations website following the conclusion of the event. I'd now like to hand the call over to Jasper's Head of Investor Relations, Alex Gray. Please go ahead, Alex.

Thank you, Tara, and thank you to those listening in today. Joining us for the prepared remarks are Jeet Mahal, CEO; and Daniel Adelman, acting CMO. Also on the line is Herb Cross, CFO, who will be available during the Q&A session. We will be presenting slides on today's call, which are available via the webinar link and posted to our Investor Relations website. During today's event, we will be making forward-looking statements based on our estimates and assumptions and our current expectations and projections about future events. All statements other than statements of historical fact made during today's event are forward-looking statements. These statements are subject to a number of risks, assumptions and uncertainties, any of which may be significant, and our actual results may differ materially and adversely from those stated or implied in any forward-looking statements. For description of risks and factors that could affect our future financial results and business, please refer to the disclosure in the accompanying slides, our most recent Forms 10-K and 10-Q and the reports that we have filed or may file on Form 8-K with the Securities and Exchange Commission. All of our statements are made as of today, January 8, 2026, based on information currently available to us. We can give no assurance that these statements will prove to be correct, and you should not rely on any forward-looking statements as predictions of future events. We undertake no duty to update any forward-looking statements, except as required by law. I'll now hand the call over to Jeet Mahal. Jeet?

Good morning, and thank you for joining us this morning. We're excited to share updated data from our BEACON study in patients with chronic spontaneous urticaria and our open-label extension study in patients who have previously participated in either the BEACON study or in our SPOTLIGHT study evaluating patients with chronic induced urticaria. First, I'd like to thank Ron Martell, Jasper's previous CEO, for his work at Jasper since he took on the role in 2022. Ron led the company through a pivotal period, refocusing briquilimab development into mast cell driven diseases and helped us achieve positive proof-of-concept data in multiple patient populations, including CSU, CIndU and allergic asthma. Turning to today's data update. We are very pleased with the updated results in both the BEACON and the open-label extension study as briquilimab continues to demonstrate rapid onset of disease control, durable efficacy and a safety profile favorable for chronic dosing. We believe this favorable efficacy and safety profile is driven by the unique properties of our antibody. Briquilimab binds to the KIT receptor with high affinity, directly blocking receptor signaling and triggering apoptosis of mast cells. The rapid and high Cmax following subcutaneous dosing leads to mast cell depletion, deep UAS7 score reduction and disease control in the first 2 to 4 weeks. Drug clearance near the end of an 8-week dosing cycle allows for reduction of KIT-related AEs and improved tolerability profile for patients. Today's update includes data from 8 additional patients in the BEACON study who were given an initial dose of 240 milligrams followed by 180 milligrams every 8 weeks. Six of the 8 patients received briquilimab and 2 received placebo. Of the 6 patients in the active arm, 5 achieved complete response by week 3 with 4 of 6 achieving a complete response at week 12. We have also enrolled 2 additional patients in the 240-milligram 8-week cohort, but those patients have not reached the 12-week primary efficacy endpoint, so no data will be reported on today. Today's update also includes data from 63 patients in our open-label extension study given 180 milligrams of briquilimabs every 8 weeks. With median exposure of over 200 days, we are pleased to report that briquilimab has been efficacious and well tolerated, demonstrating a favorable chronic safety profile with low incidence of KIT-related adverse events. Overall, the data from BEACON and OLE support commencing a Phase IIb study as part of the CSU registrational program expected to start in the second half of 2026. We expect this study to be conducted in approximately 75 to 100 adult patients with CSU evaluating 2 effective dose regimens versus placebo. I will now hand it over to Dan to review the data in more detail.

Thank you, Jeet, and good morning. As Jeet noted, we are very pleased by the updated results we're presenting today. Among the additional patients enrolled in BEACON, we observed deep reductions in tryptase levels and meaningful clinical responses with a mean reduction of UAS7 scores of 31 points at week 12. Additionally, onset of effect was rapid with complete responses reported in the majority of patients by week 2. Overall, 5 of 6 patients achieved a CR after initial 240-milligram loading dose and 4 of 6 patients reported a CR at week 12 on the 180-milligram maintenance dose. In the CIndU portion of the open-label extension, we observed durable clinical responses following repeat dosing of briquilimab, where 65% of the CIndU patients achieved either a CR or a PR at week 16, which was 8 weeks following the last dose. In the CSU portion of the open-label extension, we saw progressive UAS7 reductions over time, supporting the possibility of 180 milligrams as a maintenance dose in CSU. Across both studies, briquilimab continues to demonstrate the potential for a differentiated safety profile. Lastly, and perhaps most importantly, we believe the data gathered to date are sufficient to enable final dose selection for our Phase IIb study in CSU. Before reviewing the additional BEACON data in detail, I will provide a quick reminder on the trial design. The patients we are discussing today are from Cohort 9.1 in which the patients were administered a loading dose of 240 milligrams followed by 180 milligrams every 8 weeks. There were 8 additional patients enrolled in this cohort, 6 of whom received active drug and 2 received placebo. We also enrolled 2 patients in Cohort 8.1, evaluating a 240-milligram dose every 8 weeks, but these patients have not yet reached the 12-week efficacy endpoint. Moving over to the pharmacodynamic results. As you can see, a rapid and deep reduction in tryptase levels was observed in these patients, which was consistent with what was observed in other cohorts. On this slide, we show weekly mean UAS scores through week 12 for Cohort 9.1. At baseline, the patients in this cohort were highly symptomatic as evidenced by the high mean UAS scores. As with the tryptase, the 240-milligram loading dose drove rapid and clinically significant reductions in UAS7 scores and those reductions were largely sustained with a mean UAS7 drop of 31 points at week 12. We show the corresponding response data for Cohort 9.1 with the percentage of patients achieving complete responses defined as a UAS7 score equal to 0, shown in blue and the percentage of patients achieving CR or well-controlled disease defined as a UAS7 score less than 6 in orange. Five of 6 patients achieved a CR by week 3 with 4 of 6 reporting a CR at the week 12 endpoint. Moving on to safety, briquilimab was well tolerated and demonstrated a favorable safety profile in this cohort shown here in the gray box. As the table shows, there were no dose-limiting toxicities reported and no discontinuations due to treatment-related adverse events among patients enrolled in this cohort. This slide shows safety and tolerability observations possibly related to KIT blockade. In Cohort 9.1, one patient experienced a taste change and another experienced a neutrophil count decrease, which was transient and resolved while on study. KIT-related safety events remain generally limited to low-grade events, the majority of which resolved during repeat dosing and none of which resulted in discontinuations or dose delays. The results give us confidence in the safety and tolerability profile of briquilimab and inform the dosing strategy for Phase IIb with the goal of minimizing the severity and duration of adverse events associated with KIT blockade. Moving to the open-label extension. This slide shows the design of the study. Following completion of their dosing and follow-up periods, patients enrolled in both the BEACON study and the SPOTLIGHT CIndU study were eligible to roll over to the open-label extension evaluating briquilimab at 180 milligrams administered every 8 weeks. We're reporting the safety data from 63 patients and reporting efficacy data from the 53 patients who have completed at least 12 weeks on study. On this slide, we show the clinical responses for the 17 CIndU patients enrolled in the open-label extension. Of note, in the CIndU portion of the OLE, efficacy challenges were conducted at weeks 2, 8, 16 and 24. With the exception of the week 2 assessment, all measurements were taken 8 weeks following the last dose. In this study, we continue to see rapid onset of symptom control in CIndU with 69% of patients achieving complete or partial responses at week 2, and that effect was durable with 65% of patients maintaining responses at week 16. Moving to the CSU portion of the open-label extension. This slide shows UAS7 data for 36 patients through week 20 in the left panel and those achieving either a complete response or well-controlled disease in the right panel. As you can see, we continue to observe a progressive reduction in UAS7 scores over time. We will continue to see rapid onset of effect with responses observed as early as week 1 and as indicated in the UAS7 data, these responses appear to increase over time with 62% achieving a complete response at week 20, 4 weeks after the administration of the third dose. Finally, we have safety and tolerability data from the CSU and CIndU patients enrolled in the open-label extension. We now have 63 patients treated at 180 milligrams every 8 weeks with a median follow-up of over 200 days and briquilimab continues to demonstrate a favorable safety profile. As with BEACON and SPOTLIGHT, safety and tolerability observations possibly related to KIT inhibition were infrequent and generally limited to low-grade events, the majority of which resolved during repeat dosing. With that, I'll now hand the call back over to Jeet.

Thank you, Dan. Before we wrap up, I'll share a couple of brief thoughts of how we believe these data support a differentiated and competitive product profile for briquilimab in patients with CSU. As you can see at 12 weeks, both the open-label extension study and the additional patients enrolled in the BEACON study show a robust rate of disease control after just the second dose of briquilimab. We believe that this data compares favorably to published data with other antibodies that bind to the KIT receptor. On this slide, we showed the weekly disease activity score for the additional BEACON Cohort 9.1 patients described today, along with the previously shared BEACON 240-milligram and 360-milligram single dose cohorts and the data from the CSU patients in the open-label extension. Across these cohorts, we see a rapid and deep reduction in disease activity score 2 to 3 weeks after the initial briquilimab dose. We believe that this rapid efficacy is driven by briquilimab's unique mechanism action as well as briquilimab's ability to deliver a rapid and high Cmax following subcutaneous dosing. Towards the end of the 8-week dosing cycle, we see some recovery of disease activity consistent with drug clearance based on briquilimab's half-life. We believe that this relaxation of KIT signal suppression allows us to dose briquilimab in a manner to minimize unwanted KIT-related adverse effects and potentially deliver an improved tolerability profiles for patients with CSU or CIndU. To wrap up, I'd reiterate a few of our key takeaways from this update. First, briquilimab continues to demonstrate the ability to drive rapid, deep and durable disease control, including clinical complete responses. Second, we now have sufficient repeat dose safety data available that support a favorable chronic safety profile characterized by low frequency, low-grade and transient KIT-related AEs. Third, we believe that the data are now sufficient to enable selection of 2 efficacious dose regimens for a Phase IIb study in patients with CSU. We are targeting commencement of this study in the second half of 2026. Finally, we believe the totality of data from the BEACON, SPOTLIGHT and open-label extension studies support a compelling product profile for briquilimab in chronic urticarias with briquilimab's unique drug properties delivering rapid disease control while minimizing KIT-related AEs. With that, we'd like to open the meeting to questions. Operator?

Great. Thank you, Jeet. [Operator Instructions] So our first question comes from Yaron Werber at TD Cowen.

Jeet, congrats on the promotion. Maybe I know you want to limit to one, but if you don't mind, I'm going to ask more than one because this is just a bit important. Maybe can you just give us a little bit of a sense with the change in CEO at this point? What was the thinking behind it? And why do it now, so to speak? And then secondly, as you think about the dose selection for the Phase IIb, do you have any sense what doses you are going to take forward? Because one of the slides does show that at 8 weeks, there is sort of a rebound of efficacy, so is Q8 week the right dosing? And then finally, the Phase IIb starts keeps on getting pushed out. What gives you confidence that you really can hit the second half guidance?

Thanks, Yaron. Well, let me start with the timing and rationale behind the change of the CEO. Yes, this was a decision driven by the Jasper Board, looking at the development stage of the company and the next stage of leadership needed to move the program forward into Phase IIb and pivotal studies. So the Board asked that I become the CEO given my track record in development of multiple therapeutics from Phase I or Phase II through BLA or NDA submission. With regards to the Phase IIb dose selection, this data is looking really fresh, so I think it's a little premature to comment on specific doses, but needless to say, we'll be taking all of this data along with the previous data, updating our models, our pharmacometric and pharmacodynamic models, our disease response models and looking for 2 dose regimens for the next study. We will come back to you and others when we have a better idea of what those are. We don't think that will take too long, but we want to make sure we get it right. Finally, your question about starting the study in the second half of 2026. Part of that is driven by the time line it took to generate this data and the timing we need to analyze that data to be confident that we are selecting the right doses and then having those discussions with the regulatory bodies. We believe that we're in good shape for starting the study later this year as we have sufficient drug supply at this point to run the study, and we have the operations in place to get it off the ground.

Our next question comes from Gavin Clark-Gartner at Evercore.

I just wanted to ask on the path forward for the Phase IIb, like is the plan still to run an adaptive Phase IIb/III type of design? Or are you planning to run a separate Phase IIb and then go into Phase III after that? And also, what's like the capital requirements or timing to reach that Phase IIb data portion?

Yes. Thanks, Gavin. Yes, right now, the protocol is still an operationally adaptive Phase IIb/III. Now where we are today, we want to make sure that we have adequate time between the IIb and III portions to make sure that we're making the right dose selection. But in any case, that can be done in a single protocol with minimal breakage in time between the IIb results in the start of the Phase III. That would also require us to need to run a separate Phase III once we start the Phase III portion of that first study in order to have too well-controlled or too adequately controlled studies for registration. With regards to capital requirements, I'll pass that to Herb.

Thanks for the question, Gavin. I think from a Phase IIb perspective, we haven't given kind of specific guidance on that. And suffice it to say, our current guidance is that existing capital gets us through the middle of this year and into the third quarter of this year, so there will be a need to raise capital, but we're not giving specific guidance on what those capital requirements are at this point.

Our next question comes from Matt Phipps at William Blair.

Congrats. Happy for you to get this promotion as CEO. I was wondering if you could give us maybe some context on how meaningful a UAS7 rebound from, say, 5 to 10 is in that outer weeks versus having less on-target adverse events like hair color change and taste change for a patient. And then I guess, at what point or maybe when do you think about potential partnerships to help fund some of the Phase IIb and into Phase IIIs?

So let me answer the question about partnerships, and then I'll pass it over to Dan about the question regarding UAS7 disease activity return, balancing that versus the AE profile. Yes. Look, in terms of partnerships, this is I think, a very compelling product that could really benefit from a larger partner looking at multiple indications. We've done the proof-of-concept studies here in CSU and CIndU, previously reported the allergic asthma data and have previously reported animal proof-of-concept data in the Jasper Mouse model across multiple other diseases. So Jasper, I think, is in good shape to start the Phase IIb for CSU, but really to pursue all of those indications in a broad life cycle plan would take the resources of a larger organization. So I think whenever that may occur, that is something that the company would take very seriously. With that, I'll pass it over to Dan.

So Matt, thanks for the question. Really, it comes down to the question of the return of symptoms as indicated by a UAS7 that goes from, say, less than 6 up to somewhere around 10 in a patient and is this worth the trade-off for reduction of those undesirable on-target KIT effects. And I think each individual patient has to ultimately be the judge of that. A lot of these patients are starting off with UAS7s in the 20s and 30s and even maybe sometimes low 40, and so a reduction of symptoms down to less than 6 is incredible relief. Many of them see flares of their disease almost on a daily basis. And so a return of symptoms from, say, 1, 2, 3 or 4 up to 10, followed by another dose and a reduction is probably a huge improvement in the quality of life over what they had prior to treatment. And if you can reduce things like the undesirable KIT inhibition effects, it's probably worth it. But as I said at the very beginning, each individual patient is going to have to be the judge for that.

Our next question comes from Josh Warman at Citizens JMP.

This is Josh on for Silvan. Congrats, Jeet, on the promotion. Maybe just on the Phase IIb trial, maybe can you discuss what sort of the gating factors are in that direction? And then also what are the processes or how many -- first of -- how many sites will need to be activated in order to run that study? And then sort of what will be the processes in site selection going forward to ensure that you enroll the patient population that will be effective?

Thank you, Josh. Maybe, Dan, do you want to take on the questions about [site] selection and then I can talk about the operational issues.

Sure. And did you say the patient selection or…

Site selection.

Site selection. So we are going to be looking at sites where we have investigators who have significant experience in the management of patients with CSU, preferably those who've participated in clinical trials previously. But we will be looking exclusively at allergists and dermatologists who have significant experience in the management of patients with CSU. That's first and foremost. And that's critically important to make certain that we are enrolling patients who, in fact, have CSU. That being said, as we've mentioned previously, even the very best of the key opinion leaders in the management of CSU will sometimes get the diagnosis wrong up to 20% to 30% of the time. But we want to make certain that we minimize the number of patients who have -- who are enrolled, who don't have CSU. So that's how we're going to be selecting our sites. As far as the number of sites, one of the things that we will go through in our operations group is feasibility assessments for each of these sites, and then that will help us determine the number of patients that we can expect to be enrolled per site per month, and then we will determine the number of total sites.

Yes. And Josh, in terms of the gating factors, there's -- of course, it's a pretty complex path to get a multi-country, multisite Phase 2b study off the ground with high degree of quality as this is such an important step for the company. And there's a number of items. We don't wait to do them all in serial, when possible, we do as many in parallel as possible, but some of them are in order, right? So one of our first things that we need to do here is analyze the data that we presented today in more detail in order to drive dose selection, which would then allow us to finalize protocols, submit to regulatory authorities, start the kitting, the manufacturing and as Dan also noted, there's going to be a lot of focus on making sure that we have the right processes in place to drive quality site selection and patient inclusion and exclusion criteria. So we think that it's better to be a bit more careful on the front end in order to ensure high-quality conduct and results by the time the study is over.

Our next question comes from Emily Bodnar at H.C. Wainwright.

Looking at the most recent Cohort 9.1, it looks like maybe the first dose with the 240 mg had a better CR rate than once patients kind of transition to the 180 mg. So curious to get your thoughts on how you're expecting the 240 mg Q8 weekly dose to perform based on these initial results.

Dan, you want to give some thoughts and I'll add if needed.

So Emily, thanks for the question. It's far more complicated than you might imagine because some of these patients may be quite heavy, some of them might be quite light. And I think one of the things that we're going to have to do before we finalize our dose selection for Phase IIb is to see on a weight-adjusted exposure basis where the right -- the optimal dose might actually be. And so while I think we are pretty clear that the 240 mg is a decent loading dose, we may need to make some adjustments for patients who are heavier or patients who are considerably lighter. And as you could see, while we did have some return of the UAS7 increasing towards the end of the dosing interval with subsequent doses at 180, the UAS7 majors kept progressively going down. And so as Jeet has mentioned previously, we have to do a lot of clear modeling and analytics of the current data prior to landing on what our final dose selections will be for the Phase IIb.

Our next question comes from Justin Zelin at BTIG.

Congrats, Jeet. So you outlined on the Phase IIb as a 75- to 100-patient study with 2 active dose regimens versus placebo. And you also mentioned that there's a known 20% to 30% misdiagnosis rate in CSU. So I just was curious on how you're thinking about powering assumptions for the Phase IIb and as well as based on the data you presented today, how are you currently thinking about incorporating a loading dose into the Phase IIb design?

Well, I'll take the powering one and then pass the question about loading dose over to Dan. So as you know, the primary efficacy endpoint for regulators is the change in the UAS7 score. For the BEACON study here, we picked 12 weeks, right? So we already have quite a bit of data to analyze the doses that we've studied and importantly, as Dan mentioned, the exposure levels versus placebo. And so we can model various efficacy rates with regards to the UAS7 changes versus placebo. We can model and do sensitivity analysis on misdiagnosis rates or inclusion of patients without mast cell driven CSU and those are all the pieces that we take into account when looking to actually power our Phase IIb study. Right now, the 75 to 100 is preliminary estimate. We don't expect that to change significantly, but it may be plus or minus a bit. With that, I'm going to ask Dan to weigh in on the concept of an initial or loading dose versus maintenance doses.

Yes. For the Phase IIb, we anticipate and nothing is finalized at this point, but what we're anticipating is that we will have a 3-arm study, 1 -- 2 different dose regimens and then a placebo group. One of those dose regimens is likely to be a load followed by maintenance and the other is likely to be a steady fixed dose on an 8-week dosing interval. As Jeet mentioned, we still have a lot of work to do analyzing the data that we have as well as do some modeling to really ultimately land on the final selection. That being said, we do have enough data to be able to make an informed choice of those 2 active dosing regimens, and we'll be more forthcoming with that once we've completed our analysis. As far as dealing with the 20% to 30%, that's baked into -- who may not have CSU, that's going to be baked into our power calculations.

Thank you for the questions, Justin. So this concludes today's Q&A session and today's event. We thank you for joining. You may now disconnect.