JSPR 8-K
Jasper Therapeutics, Inc. (JSPR)
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CURRENT REPORT
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Item 8.01. Other Events.
On June 14, 2025, Jasper Therapeutics, Inc. (the “Company”), issued a press release reporting positive data from the 180mg cohort of the Company’s SPOTLIGHT Phase 1b/2a study of subcutaneous briquilimab in adult participants with chronic inducible urticaria and disclosing that the Company will hold a conference call and webinar at 8:00 am EST on June 16, 2025 to present the data from the 180 mg cohort in the SPOTLIGHT Phase 1b/2a study.
A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference. A copy of the presentation to be used in connection with the conference call and webinar on June 16, 2025 is attached as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference.
Item 9.01. Financial Statements and Exhibits.
(d) Exhibits.
| Number | Description | |
| 99.1 | Press Release, dated June 14, 2025. | |
| 99.2 | Presentation—Jasper Therapeutics: SPOTLIGHT Data Update, dated June 16, 2025. | |
| 104 | Cover Page Interactive Data File, formatted in Inline Extensible Business Reporting Language (iXBRL). |
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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
| JASPER THERAPEUTICS, INC. | ||
| Date: June 16, 2025 | By: | /s/ Herb Cross |
| Name: Herb Cross | ||
| Title: Chief Financial Officer | ||
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Exhibit 99.1
Jasper Therapeutics Reports Positive Data from
180mg Cohort in
SPOTLIGHT Study of Briquilimab in Chronic Inducible Urticaria
11 of 12 participants (92%) enrolled in the 180mg cohort achieved a complete response
12 of 12 participants (100%) in the 180mg cohort achieved a clinical response
Tryptase levels below the lower limit of quantification observed in 10 of 12 participants (83%)
No serious adverse events and no grade 3 or higher adverse events reported in the 180mg cohort
Company to host conference call and webinar on Monday, June 16, at 8:00 a.m. EDT
REDWOOD CITY, Calif., June 14, 2025 (GLOBE NEWSWIRE) – Jasper Therapeutics, Inc. (Nasdaq: JSPR) (Jasper), a clinical stage biotechnology company focused on development of briquilimab, a novel antibody therapy targeting KIT (CD117) to address mast cell driven diseases such as chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) and asthma, is presenting data from the 180mg cohort of the Company’s SPOTLIGHT Phase 1b/2a study of subcutaneous briquilimab in adult participants with CIndU at the European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress. Briquilimab (subcutaneous) administration resulted in deep disease control at 180mg, with 12 of 12 participants (100%) enrolled in the cohort achieving a clinical response within the 8-week preliminary analysis period. The efficacy observed was rapid and durable, with 8 of 12 participants (66%) achieving clinical response by week 2, and 7 of 12 participants (58%) maintaining clinical response through week 8. Briquilimab continued to be well tolerated in the study, with no serious adverse events (SAEs) and no grade 3 or higher adverse events (AEs) reported in the 180mg cohort.
“We are very pleased by the updated results from the SPOTLIGHT study, with briquilimab driving complete responses in over 90% of CIndU participants enrolled in the 180mg cohort,” said Ronald Martell, President and Chief Executive Officer of Jasper. “In addition to the responses observed, we are pleased that briquilimab continued to be well tolerated in the study. Taken together with the results observed thus far in the BEACON study in CSU, these data demonstrate the ability of briquilimab to support optimal biologic dosing by rapidly delivering robust and durable control of urticaria symptoms, along with a potentially differentiated safety profile. On behalf of the entire Jasper team, I’d like to thank both the investigators and the patients who participated in SPOTLIGHT, along with their families and caregivers.”
SPOTLIGHT Study Design and Data Summary:
The SPOTLIGHT study is a Phase 1b/2a open label clinical trial evaluating a single dose of subcutaneous briquilimab in adult participants with cold urticaria (ColdU) or symptomatic dermographism (SD), the two most prevalent sub types of CIndU, who are refractory to antihistamines. The study enrolled 27 participants across three dose cohorts, 40mg (n=3), 120mg (n=12), and 180mg (n=12). The primary endpoints are safety and tolerability of briquilimab and secondary endpoints are focused on clinical activity and PK/PD, including measurement of serum tryptase.
Among the 12 participants enrolled in the 180mg cohort, 3 were diagnosed with ColdU (25%) and 9 with SD (75%). Participants had high disease burden as assessed by provocation threshold testing. In the 180mg cohort, mean baseline TempTest® threshold was 18.7°C (range: 10-26°C) for ColdU participants, and mean baseline FricTest® threshold was 3.7 of 4 (range: 3-4) for SD participants.
12 of 12 participants (100%) enrolled in the 180mg dose cohort achieved a clinical response to provocation testing within the 8-week preliminary analysis period following treatment. 11 of 12 participants (92%) treated in the cohort achieved a complete response (CR) with either their critical temperature threshold improving to at least 4°C for ColdU participants or their FricTest® score improving to 0 for SD participants, and 1 of 12 participants achieved a partial response (PR) as their best response. Complete responses in TempTest® or FricTest® were observed as early as 1 week following dosing in the 180mg cohort, with 8 of 12 participants (66%) achieving CR or PR by week 2.
Overall, 22 of 27 participants (81%) enrolled in the study achieved a CR and 26 of 27 participants (96%) achieved a CR or PR.
| Briquilimab 40mg (n=3) | Briquilimab 120mg (n=12) | Briquilimab 180mg (n=12) | Briquilimab All doses (n=27) | |||||
| Complete Response, n (%) | 1 (33.3%) | 10 (83.3%) | 11 (91.6%) | 22 (81.5%) | ||||
| ColdU, n | 0 | 3 | 3 | 6 | ||||
| Symptomatic Dermographism, n | 1 | 7 | 8 | 16 | ||||
| Partial Response, n (%) | 2 (66.7%) | 1 (8.3%) | 1 (8.4%) | 4 (14.8%) | ||||
| ColdU, n | 1 | 0 | 0 | 1 | ||||
| Symptomatic Dermographism, n | 1 | 1 | 1 | 3 | ||||
| Complete or Partial Response at any time, n (%) | 3 (100%) | 11 (91.6%) | 12 (100%) | 26 (96.3%) |
At the 8-week timepoint following treatment, 7 of 12 (58%) participants in the 180mg cohort maintained an ongoing clinical response, with 5 participants achieving CR and 2 participants achieving PR.
Mean baseline serum tryptase for participants in the 180mg cohort was 5.1 ng/ml (standard deviation: 2.29 ng/ml). Significant reductions in tryptase were observed as early as the week 1 assessment and were correlated with the onset of clinical responses. Tryptase measurements below the lower limit of quantification were observed in 10 of 12 participants (83%) in the 180mg cohort.
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Briquilimab was well tolerated in the study. No SAEs or AEs ³ grade 3 were reported in the 180mg cohort. Furthermore, there were no reported AEs related to hair or skin color changes. 2 of 12 participants (17%) enrolled in the 180mg cohort experienced taste change/hypogeusia. Mild, transient drops in neutrophil counts were observed, with 6 of 12 participants (50%) experiencing grade 1 or grade 2 neutrophil count decreases which resolved in a median of 16 days. 5 of the 6 participants who experienced neutrophil count decreases were diagnosed with concurrent viral infections that may have contributed to observed decreases.
“It is exciting to see additional clinical data showing that treatment with briquilimab can lead to deep clinical benefit shortly after administration in a difficult-to-treat antihistamine refractory CIndU patient population,” said Martin Metz, M.D., Professor of Dermatology and Allergy Charité – Universitätsmedizin Berlin. “Notably, the safety and tolerability results observed in both the SPOTLIGHT and BEACON studies thus far show that the adverse events possibly caused by briquilimab are mostly low frequency, low grade, and resolve quickly. Patients with CIndU currently have very few treatment options, and I look forward to continuing to support the development of novel therapeutics to treat this debilitating disease.”
Conference Call / Webinar
Jasper will host a conference call and webinar on Monday, June 16, 2025, at 8:00 a.m. EDT. A live question and answer session with management will follow the formal presentations. A link to the webinar, including presentation slides, can be found here. To access the live conference call via phone, dial 1-844-826-3033 from the US or 1-412-317-5185 from outside the US, or click here. The conference ID is 10200147, and the conference call passcode is 6392607.
The presentation slides and a link to the live and archived webinar will also be available on the Events & News – Events page of Jasper’s Investor Relations website.
About Jasper
Jasper is a clinical-stage biotechnology company focused on developing briquilimab as a therapeutic for chronic mast cell diseases. Briquilimab is a targeted aglycosylated monoclonal antibody that blocks stem cell factor from binding to the cell-surface receptor KIT, thereby inhibiting signaling through the receptor. This inhibition disrupts the critical survival signal, leading to the depletion of the mast cells via apoptosis which removes the underlying source of the inflammatory response in mast cell driven diseases such as chronic urticaria and asthma. Jasper is currently conducting clinical studies of briquilimab as a treatment in patients with CSU, CIndU or asthma. Briquilimab has a demonstrated efficacy and safety profile in patients and healthy volunteers, with positive clinical outcomes in CSU and CIndU. For more information, please visit us at www.jaspertx.com.
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Forward-Looking Statements
Certain statements included in this press release that are not historical facts are forward-looking statements for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995. Forward-looking statements are sometimes accompanied by words such as “believe,” “may,” “will,” “estimate,” “continue,” “anticipate,” “intend,” “expect,” “should,” “would,” “plan,” “predict,” “potential,” “seem,” “seek,” “future,” “outlook” and similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These forward-looking statements include, but are not limited to, statements regarding briquilimab’s potential, including with respect to its potential in mast cell driven diseases such as CSU, CIndU, and asthma; briquilimab’s ability to support optimal biologic dosing by rapidly delivering robust and durable control of urticaria symptoms along with a potentially differentiated safety profile; and the potential for treatment with briquilimab to lead to deep clinical benefit shortly after administration in a difficult-to-treat antihistamine refractory CIndU patient population. These statements are based on various assumptions, whether or not identified in this press release, and on the current expectations of Jasper and are not predictions of actual performance. These forward-looking statements are provided for illustrative purposes only and are not intended to serve as, and must not be relied on by an investor as, a guarantee, an assurance, a prediction or a definitive statement of fact or probability. Many actual events and circumstances are beyond the control of Jasper. These forward-looking statements are subject to a number of risks and uncertainties, including general economic, political and business conditions; the risk that the potential product candidates that Jasper develops may not progress through clinical development or receive required regulatory approvals within expected timelines or at all; the risk that clinical trials may not confirm any safety, potency or other product characteristics described or assumed in this press release; the risk that prior test, study and trial results may not be replicated in continuing or future studies and trials; the risk that Jasper will be unable to successfully market or gain market acceptance of its product candidates; the risk that prior study results may not be replicated; the risk that Jasper’s product candidates may not be beneficial to patients or successfully commercialized; patients’ willingness to try new therapies and the willingness of physicians to prescribe these therapies; the effects of competition on Jasper’s business; the risk that third parties on which Jasper depends for laboratory, clinical development, manufacturing and other critical services will fail to perform satisfactorily; the risk that Jasper’s business, operations, clinical development plans and timelines, and supply chain could be adversely affected by the effects of health epidemics; the risk that Jasper will be unable to obtain and maintain sufficient intellectual property protection for its investigational products or will infringe the intellectual property protection of others; and other risks and uncertainties indicated from time to time in Jasper’s filings with the SEC, including its Annual Report on Form 10-K for the year ended December 31, 2024 and subsequent Quarterly Reports on Form 10-Q. If any of these risks materialize or Jasper’s assumptions prove incorrect, actual results could differ materially from the results implied by these forward-looking statements. While Jasper may elect to update these forward-looking statements at some point in the future, Jasper specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Jasper’s assessments of any date subsequent to the date of this press release. Accordingly, undue reliance should not be placed upon the forward-looking statements.
Contacts:
Alex Gray (investors)
Jasper Therapeutics
650-549-1454
[email protected]
Joyce Allaire (investors)
LifeSci Advisors
617-435-6602
[email protected]
Lauren Walker (media)
Real Chemistry
646-564-2156
[email protected]
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Exhibit 99.2
Jasper Therapeutics SPOTLIGHT Data Update June 16, 2025
2 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION Safe Harbor Statements Forward - Looking Statements Certain statements in this Presentation include “forward - looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. All statements other than statements of historical fact contained in this Presentation, including statements regarding Jasper’s future opportunities and prospects, including milestones, potential regulatory filings and the anticipated timing thereof, patient enrollment, future timelines, business strategy, plans and objectives for future operations, Jasper’s ability to obtain additional funding for its operations in this or future offerings and its expectations related to the use of any net proceeds from this offering are forward - looking statements. Jasper has based these forward - looking statements on its estimates and assumptions and its current expectations and projections about future events. These forward - looking statements are subject to a number of risks, uncertainties and assumptions, including those contained in the "Risk Factors" section of the Company's Annual Report on Form 10 - K for the year ended December 31, 2024, Quarterly Reports on Form 10 - Q and Current Reports on Form 8 - K that the Company has subsequently filed or may subsequently file with the SEC. In light of these risks, uncertainties and assumptions, the forward - looking events and circumstances discussed in this Presentation are inherently uncertain and may not occur, and actual results could differ materially and adversely from those anticipated or implied in th e forward - looking statements. Accordingly, you should not rely upon forward - looking statements as predictions of future events. Jasper undertakes no obligation to update publicly or revise any forward - looking statements for any reason after the date of this Presentation or to conform these statements to actual results or to changes in Jasper's expectations. Industry and Market Data Certain data in this Presentation was obtained from various external sources, and neither the Company nor its affiliates, adv isers or representatives has verified such data with independent sources. Accordingly, neither the Company nor any of its affiliates, advisers or representatives makes any representations as to the accuracy or completeness of that data or undertakes any obligation to update such data after the date of this Presentation. Such data involves risks and uncertainties and is subject to change based on various factors. Trademarks The trademarks included herein are the property of the owners thereof and are used for reference purposes only. Such use should not be construed as an endorsement of the products or services of the Company.
B RIQU ILIMAB IS AN INVESTIGATIVE DRUG AND IS NOT APPROVED FOR ANY INDICATION 3 Today’s Agenda • Opening Remarks • SPOTLIGHT 180mg Results Summary • Upcoming Milestones and Closing Remarks • Question & Answer Session
SPOTLIGHT 180mg Results Summary
5 BRIQUILIMAB IS AN INVESTIGATIVE DRUG AND IS NOT APPROVED FOR ANY INDICATION CIndU can be a severe & debilitating disease with negative impacts on quality of life for patients • Chronic inducible urticaria (CIndU) is a debilitating inflammatory condition of the skin with a specific trigger such as heat, cold, sunlight, rubbing or scratching the skin or tight clothing • Mast cell degranulation, leading to the release of histamine and other inflammatory mediators, is the key driver of severe itching, hives and angioedema in CIndU patients • CIndU patients suffer both physically and psychologically. Severe disease has a similar negative impact on QoL as other dermatologic diseases like plaque psoriasis • Targeting the KIT receptor with briquilimab disrupts a critical survival pathway on mast cells leading to mast cell apoptosis and disease resolution 1. Munoz M, et al. Current Allergy and Asthma Reports June 2024 2. Ozdemir SO, et al. JEADV Mar 2024 3. Maurer M, et al. J Allergy Clin Immunol 2017 4. Nikolaev I, et al. EAACI Hybrid Congress, July 1 - 3, 2022 5. Mauer M, et al. EAACI Hybrid Congress, May 31 - June 3 2024
Screening/Eligibility • Diagnosis of Cold Urticaria (ColdU) or Symptomatic Dermographism (SD) for ≥ 3 mos • H1 - antihistamine - failed • 18+ years • 18 - 65 years of age Study Operations • EU Lead: Martin Metz, MD • ~5 sites in the EU • N = ~27 Key Assessments • Provocation Test: TempTest ® (ColdU), FricTest ® (SD) • Disease Scores: UCT • Mast Cell Depletion & Recovery: Serum Tryptase, Skin Biopsies • Safety: TEAEs, SAEs Provocation Test Measured at 12 Weeks (Primary Endpoint) Provocation Tests Used for Clinical Evaluation 40 mg 120 mg 180 mg n=3 n=12 n=12 Symptomatic Dermographism FricTest ® CR – No response at Fric Level 4 PR – ≥ 2 pin improvement Cold Induced Urticaria TempTest ® CR – Negative test at ≤ 4ºC PR – Improvement by ≥ 4ºC Single Dose Dose Patients Schedule Key Assessments & Follow - up 12 Week Efficacy Observation Period (6 Week Preliminary Analysis) + 24 Week Additional Safety Observation Phase 1b/2a SPOTLIGHT Study in Chronic Inducible Urticaria Open - label, single ascending dose study Open - Label Extension 6 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION Patients may roll over to open - label extension study evaluating briquilimab at 180mg Q8W
Rapid Onset of Deep and Durable Efficacy Observed at 180mg Dose 7 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION Depth of Response • 12 of 12 patients (100%) at 180mg achieved clinical response following single - dose of briquilimab • 11 of 12 patients (92%) at 180mg achieved complete response (CR) • 10 of 12 patients (83%) at 180mg had tryptase measurements below lower limit of quantification Rapid Onset of Effect • 67% of 180mg patients with CR or partial response (PR) at week 2 assessment Durability of Effect • 5 CRs and 2 PRs maintained at week 8 (58%, 7/12), durability assessment ongoing
SPOTLIGHT Baseline Demographics Briquilimab 180mg Briquilimab 120mg Briquilimab 40mg (n=12) (n=12) (n=3) 39.9 (16.0) 46.4 (13.8) 35.3 (8.0) Age (years), mean (SD) 7 (58%) 8 (67%) 1 (33%) Female, n (%) 86.5 (54 - 104) 99.0 (57 - 115) 86.0 (69 - 94) Weight (kg), median (range) 3 4 1 Cold Urticaria, n 9 8 2 Symptomatic Dermographism, n Baseline Provocation Threshold 18.7 (10 - 26) 20.8 (15 - 27) 16.0 (16 - 16) TempTest TM ( ƒ C), mean (range) 3.7 (3 - 4) 3.9 (3 - 4) 3.5 (3 - 4) FricTest TM (Pin Count), mean (range) 6.5 (2.7) 6.3 (3.3) 3.7 (2.5) Urticaria Control Test (UCT) score, mean (SD) 5.1 (3.2 - 11.2) 7.6 (3.6 - 25.7) 4.7 (4.1 - 5.3) Tryptase (ng/ml), mean (range) 8 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
* All values below LLOQ (1.0 µg/L) are represented as 0 µg/L 9 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION SPOTLIGHT: Dose dependent reductions in serum tryptase Reduction to below Lower Limit of Quantification (LLOQ) (1 µg/L) seen in 83.3% (10/12) participants at 180mg
SPOTLIGHT Efficacy Evaluation Briquilimab 180mg single dose achieved 92% (11 of 12) CR by week 8 Briquilimab 40mg (n=3) Briquilimab 120mg (n=12) Briquilimab 180mg (n=12) Briquilimab All doses (n=27) Complete Response, n (%) 1 (33%) 10 (83.3%) 11 (92%) 22 (82%) ColdU, n 0 3 3 6 Symptomatic Dermographism, n 1 7 8 16 Partial Response, n (%) 2 (67%) 1 (8%) 1 (8%) 4 (15%) ColdU, n 1 0 0 1 Symptomatic Dermographism, n 1 1 1 3 Complete or Partial Response at any time, n (%) 3 (100%) 11 (92%) 12 (100%) 26 (96%) 10 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
SPOTLIGHT: Clinical response through 8 weeks with briquilimab 180mg (n=12) AD_T0003, AD_T0004, AD_L0001, AD_L0002 • 12 of 12 patients (100%) achieved either CR or PR by week 8 • 8 of 12 patients (67%) achieved clinical response by the week 2 assessment • 11 of 12 participants (92%) reported either CR or PR at week 6 • 9 of 12 patients (75%) achieved complete response at week 6 • 5 CRs and 2 PRs (58%) maintained through week 8, durability assessment ongoing Complete Response Partial Response 11 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
Clear Dose Response Demonstrated at 6 Weeks Post - Dose 75% CRs at 180mg dose improved on 50% CRs observed at 120mg Briquilimab 40mg (n=3) Briquilimab 120mg (n=12) Briquilimab 180mg (n=12) Complete Response, n (%) 0 (0%) 6 (50%) 9 (75%) ColdU, n 0 1 3 Symptomatic Dermographism, n 0 5 6 Partial Response, n (%) 0 (0%) 1 (8%) 2 (17%) ColdU, n 0 0 0 Symptomatic Dermographism, n 0 1 2 Complete or Partial Response at week 6, n (%) 0 (0%) 7 (58%) 11 (92%) 12 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
SPOTLIGHT Safety and Tolerability Briquilimab 40mg (n=3) Briquilimab 120mg (n=12) Briquilimab 180mg (n=12) Any adverse event 2 12 10 Any serious adverse event 0 2* 0 Any adverse event leading to discontinuation 0 0 0 Adverse event leading to death 0 0 0 0 Adverse event ≥ grade 3 0 1* *SAE: Biliary colic leading to cholecystectomy, Grade 3 Fracture of the right shoulder (both unrelated to treatment) AEs occurring in ≥3 participants: Nasopharyngitis, neutrophil count decrease, fatigue, headache, abdominal pain, COVID - 19, diarrhea, dizziness, nausea 13 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
SPOTLIGHT Safety/Tolerability Observations Possibly Related to KIT Blockade Were Generally Limited to Low Grade Events All events were grade 1 or 2 and none resulted in discontinuations Adverse Event as reported term Briquilimab 40mg (n=3) n (%) Briquilimab 120mg (n=12) n (%) Briquilimab 180mg (n=12) n (%) Briquilimab All doses (n=27) n (%) Hair color changes 0 (0) 0 (0) 0 (0) 0 (0) Skin discoloration 0 (0) 0 (0) 0 (0) 0 (0) Taste change/Hypogeusia 0 (0) 1 (8.3) 2 (16.7) 3 (11.1) Neutrophil count decreased 1 (33.3) 1 (8.3) 6* (50) 8 (29.6) * Four participants with Grade 1, two with Grade 2 ; median time to resolution 16d; four of six observations occurred proximal to a common cold diagnosis, one of six observations occurred proximal to COVID 19 diagnosis Grade 1 neutrophil count decrease defined as ANC between 1,500 – 1,700/mm 3 Grade 2 neutrophil count decrease defined as ANC between 1,000 – 1,500/mm 3 14 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
SPOTLIGHT Absolute Neutrophil Count Neutrophil counts generally remained stable, with predictable reductions which subsequently resolved 15 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
Upcoming Milestones and Closing Remarks
Takeaways 17 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION • Single 180mg dose of briquilimab demonstrated 100% clinical response in participants with CIndU • Deep reduction of tryptase observed with 83% of participants below LLOQ in 180 mg cohort • Rapid onset of symptom control with 67% achieving clinical response by week 2 • 91.6% of participants in 180 mg cohort achieved CR vs 83% in 120 mg cohort • Durability of 180mg dose shown with 58% clinical response maintained at 8 wks (5 CRs and 2 PRs) • Briquilimab was well tolerated in participants with CIndU • All possibly KIT related adverse events observed were low - grade and transient in nature • Briquilimab’s robust efficacy and safety, supports continued evaluation in chronic urticaria • Full SPOTLIGHT study results expected at medical conference in 2nd half of 2025
Key milestones = Completed = Future events/milestones 2 02 4 CSU CIndU Asthma Conferences 2 02 5 2 02 6 Registrational Phase 1b/2a Initial clinical data OLE Study Phase 1b/2a OLE E Study Clinical data all patients Next Mast Cell Indication Initial clinical data Phase 1b/2a First patient dosed Initial clinical data Phase 2b Phase 1b/2a EADV ACAAI AAAAI EAACI GA 2 LEN ATS ACAAI AAD EAACI ATS AAD AAAAI ERS EADV GA 2 LEN ACAAI ERS EADV Clinical data all cohorts 18 B RIQU ILIMAB IS AN INVES TIGATIVE DRU G AND IS NOT APPROVED FOR ANY INDICATION
Jasper Therapeutics SPOTLIGHT Data Update June 16, 2025