Slide 1: Preliminary Data from a Phase 1 Study of JSP191 in Older Adults with MDS/AML
Preliminary Data from a Phase 1 Study of JSP191, an Anti-CD117 Monoclonal Antibody, in Combination with Low Dose Irradiation and Fludarabine Conditioning: Well-Tolerated, Facilitates Chimerism and Clearance of Minimal Residual Disease in Older Adults with MDS/AML Undergoing Allogeneic HCT (NCT#04429
Slide 2: Conflict of Interest
Conflict of Interest Muffly - Advisory Boards: Pfizer, Amgen, Jazz, Medexus, CTI Biopharma, Kite; Research Funding: Astellas, Jasper, Adaptive, Kite, BMS; Consulting: Astellas Lee - Advisory Boards: Kadmon, Kite, Jazz; Research Funding: Incyte; Consulting: Fresenius Scott- Advisory Boards: BMS, Alex
Slide 3: Trends in Allogeneic HCT in the U.S. by Age
Trends in Allogeneic HCT in the U.S. by Age = <18 Years = 18-39 Years = 40-64 Years = 65+ Years N 00 Transplants, % Py P 0H HM gi agg ah My sE gH gag” y CIBMTR “Transplants for AML, ALL, MDS, NHL, HD, MM 14
Slide 4: JSP191 Designed to Block CD117 (Stem Cell Factor Receptor) Signaling
JSP191 Designed to Block CD117 (Stem Cell Factor Receptor) Signaling Leading to Hematopoietic Stem Cell (HSC) Depletion without Significant Off-Target Toxicities JSP191 Blocks SCF Empty Bone Donor HSC Home Binding to CD117 Marrow Niche to Marrow Niche Stem Cell Factor (SCF) e iN — ® ee e vv ee JSP 1
Slide 5: Blockade of CD117 is Synergistic with Low Dose Radiation Leading to Donor HSC Engraftment
Blockade of CD117 is Synergistic with Low Dose Radiation Leading to Purified Donor HSC Engraftment in Immunocompetent Mouse Model Donor HSC Engraftment _ Anti-CD117 + Radiation only Low Dose Radiation 8 8 8 8 % Donor derived in Donor derived in Lin’Sca*cKit"CD150*cells (%) Mact*Gr1* cells & 250cGy —
Slide 6: Study Design
Study Design Single-arm, Open Label, in MDS/AML Patients Not Eligible for Myeloablative Conditioning Regimens Assessments: Primary endpoints: + Safety and tolerability of JSP191/TBI/Flu + JSP191 pharmacokinetics Key inclusion criteria: Experimental arm: secondary endpoints: + MDS or AML JSP191 0.6 m
Slide 7: Treatment Schema
Treatment Schema Outpatient Conditioning Regimen TB Bone marrow _Fludarabine (Flu) 200- — Mobilized JSP191 aspiration/biopsy 30 mg/m2/day 300 cGy PB HCT | | | | oo El |-|-|- 2 Day (TD) Real-time PK measurements and modeling were used to determine Flu start date * TBlincreased from 200 to 300 cGy aft
Slide 8: MDS & AML Patient Characteristics
MDS & AML Patient Characteristics Character Al Patients Patients with AML Patients with MDS (w= 24) (=11)* (N= 13) Median age (range) - year 70 (62-79) 69 (62-79) 70 (67-77) Sex —no. (%) Male 18 (75%) 8 (73%) 10(77%) Female 6 (25%) 3 (27%) 3 (23% Prior AML/MDS Therapy — no. (%) Untreated or growth f
Slide 9: 0.6 mg/kg JSP191 PK: Consistent and Predictable Clearance
0.6 mg/kg JSP191 PK: Consistent and Predictable Clearance 30000: 10000. 3000: 1000 Serum (ng/mL) 300: Concentration of JSP191 in 100: 012 3 4 5 6 7 8 9 10 11 12 13 14 15 Time (days) 4JSP191 is an investigational agent and not approved for any indication.
Slide 10: Safety and Tolerability
Safety and Tolerability * No significant JSP191 infusion reactions * NoJSP191-related SAEs * No primary graft failure (one case of secondary graft failure) 4JSP191 is an investigational agent and not approved for any indication.
Slide 11: JSP191 Pharmacodynamics: Evaluation of JSP191 to Deplete HSPCs in Marrow of MDS and AML Patients
JSP191 Pharmacodynamics: Evaluation of JSP191 to Deplete HSPCs in Marrow of MDS and AML Patients Marrow il at ing and prior to ini: ‘ion of Flu/TBI 1 Fudarabine (Fu) 200- Mobilzed ssP191 30 me/m/day 300¢Gy PBHCT conwe | > | + | = EB . { 20% | 40% 60% Marrow Marrow 0% de novo AML aspirate aspirate AM
Slide 12: JSP191/Flu/TBI Conditioning Resulted in Neutropenia Followed by Neutrophil Engraftment
JSP191/Flu/TBI Conditioning in All Patients Dosed to Date Resulted in Neutropenia Followed by Neutrophil Engraftment by TD+26 204 ANC (10°/L) ANC 0.5 10°%/L 15 20 5 30 35 ‘Time Relative to Transplant Day 0 ISP191 is an investigational agent and not approved for any indication,
Slide 13: Donor Chimerism
Donor Chimerism ‘TCellChimerism Total Chimerism Myeloid Chimerism 100. 8 100. a so = 80. s g 2 3 e2 04} \ H 3 60 5 3 \ 3; 3 ga 4 Si if 28 4. 25 40 2 © 200 Gy TBI a? be 8 a oe ra I 300 cGy TBI 0265690 180 360 0268690 180 360 0285680 180 360 Days after HSCT Days after HSCT Days after HSCT Median Donor
Slide 14: Multimodality Measurable Residual Disease (MRD) in patients with AML
Multimodality Measurable Residual Disease (MRD) in patients with AML* Cytogenetics, Flow Cytometry, Next Generation Sequencing SCRN TD28 TDS6 TD9O TD180 TD360 Morphologic relapse Late onset GI-GVHD T QNS giiomhelosic relapse Legend MRD status —————p +=on study 4 = completed study Morphologic relapse
Slide 15: Multimodality Measurable Residual Disease (MRD) in patients with MDS
Multimodality Measurable Residual Disease (MRD) in patients with MDS Cytogenetics, Flow Cytometry, Next Generation Sequencing SCRN TD28 - TDS56 TD90 TD180 TD360 Secondary graft failure Disease progression Legend MRD status ——> <onstudy > = completed study ——® =off study JSP191 is an investigational
Slide 16: Outcomes & GVHD reported to date
Outcomes & GVHD reported to date N = 24, median follow-up of 6 months (range 2-12 months) os Relapse & TRM o = o —— Morphologic Relapse @ 0.8 2 o8 _. TRM = g 3 0.6 2 o6 £ g a 0.4 3 0.4 8 3 0.2 E o2 -————— ° [ 0.0 0.0+ i } . 1 0 3 6 9 12 0 3 6 9 12 Months post-HCT Months post-HCT Evaluable patients:
Slide 17: Summary of Phase 1 Trial Results To Date
Summary of Phase | Trial Results To Date 0.6 mg/kg JSP191 PK is predictable and allows donor cell infusion 9-14 days after JSP191 All patients engrafted with neutrophil recovery before Transplant Day +26 MRD clearance was observed in 12 of 20 evaluable patients at last follow-up JSP191/Flu/TBI is a
Slide 18: Acknowledgements
Acknowledgements Jasper Therapeutics and the Investigators would like to thank the patients and families for participating in this clinical trial (NCT#04429191). We would also like to thank the participating clinical sites, clinical staff, and collaborators. neo nore fS @ Rusti Untvestry 07 : MEDICA