Rallybio Corporation · NASDAQ:RLYB
Rallybio — 31st Congress of the International Society on Thrombosis and Haemostasis (ISTH) 2023
14 slides from Rallybio's conference presentation, Jun 24, 2023
Slide 1: Dose-Dependent Elimination of HPA-1a Platelets by Subcutaneous RLYB212
Dose-Dependent Elimination of HPA-1a Platelets by Subcutaneous RLYB212, a Monoclonal Antibody to Prevent Fetal and Neonatal Alloimmune Thrombocytopenia Christof Geisen1, Erika Fleck1, Stephan Martin Gastón Schäfer2, Carmen Walter2, Susanne Braeuninger1, Jens Søndergaard Jensen3, Róisín Armstrong4, D
Slide 2: Disclosures for Christof Geisen
Disclosures for CHRISTOF GEISEN • Grants/research support: None • Speakers’ bureau or advisory board memberships: None • Patents for drugs or devices: Antibody Detection Method and System Patent • Other: Employee of German Red Cross
Slide 3: Presentation Learning Objectives
Presentation Learning Objectives At the conclusion of this presentation, participants will be able to: • Describe FNAIT and recognize that FNAIT is analogous to HDFN, with the distinction that it may occur during the first pregnancy • Summarize data demonstrating that RLYB212 exhibits rapid and dose
Slide 4: FNAIT Is the Platelet Counterpart to HDFN
FNAIT Is the Platelet Counterpart to HDFN1 Both are caused by antigen mismatch between maternal and fetal cells1 HPA-1a negative HPA-1a negative Anti-HPA-1a HPA-1a negative mother mother alloantibodies mother Potential for uncontrolled HPA-1a bleeding in the positive platelets fetus or newborn HPA-1
Slide 5: Precedent for Preventing Maternal Alloimmunization Is Well Established by IM and IV Anti-RhD Treatment
Precedent for Preventing Maternal Alloimmunization Is Well Established by IM and IV Anti-RhD Treatment Kinetics of concentration of RhD-positive RBCs (mean ± SD) following IV or IM administration of 1500 IU (300 μg) anti-RhD in healthy RhD-negative males More than 95% of RhD positive RBCs cleared wi
Slide 6: In a Preclinical FNAIT Model, RLYB212 Eliminated Platelets at Doses That Prevent Alloimmunization
In a Preclinical FNAIT Model, RLYB212 Eliminated Platelets at Doses That Prevent Alloimmunization RLYB212 is a novel, recombinant human anti-HPA-1a monoclonal antibody developed to prevent HPA-1a alloimmunization and FNAIT1 Elimination of transfused HPA-1a positive platelets Prevention of alloimmuni
Slide 7: RLYB212, a Novel Candidate for Prevention of HPA-1a Alloimmunization and FNAIT
RLYB212, a Novel Candidate for Prevention of HPA-1a Alloimmunization and FNAIT HPA-1a negative HPA-1a negative HPA-1a negative mother mother mother HPA-1a RLYB212 positive RLYB212 dosed platelets by small-volume, SC injection HPA-1a positive HPA-1a positive HPA-1a positive fetus fetus fetus Prophyla
Slide 8: Proof-of-Concept Study Design and Objectives
Proof-of-Concept Study Design and Objectives Phase 1b, randomized, single-blind, placebo-controlled study Randomization Male End of RLYB212 (n=9) subjects study Placebo (n=2) Platelet clearance measurement 7 days Screening Safety follow-up DAY 1 DAY 8 DAY 15 DAY 85 SC dose of Platelet Platelet chall
Slide 9: Platelet Elimination Kinetics Were Dose Dependent and Biphasic
Platelet Elimination Kinetics Were Dose Dependent and Biphasic Time course of transfused platelet elimination 7 days post-transfusion (by group) 24 hours post-transfusion (by group) 100 100 concentration of transfused platelets , % concentration of transfused platelets, % SC Placebo Mean lag phase=2
Slide 10: Platelet Elimination Kinetics Were Dose Dependent and Biphasic
Platelet Elimination Kinetics Were Dose Dependent and Biphasic Time course of transfused platelet elimination 7 days post-transfusion (by group) 7 days post-transfusion (by subject) 100 100 concentration of transfused platelets, % concentration of transfused platelets, % SC Placebo SC Placebo 90 0.0
Slide 11: Parameters of Platelet Elimination Kinetics Were SC RLYB212 Concentration Dependent
Parameters of Platelet Elimination Kinetics Were SC RLYB212 Concentration Dependent Platelet elimination half-life vs Lag time vs RLYB212 concentration before transfusion RLYB212 concentration before transfusion 20 8 0.09 mg SC RLYB212 0.09 mg SC RLYB212 18 0.29 mg SC RLYB212 0.29 mg SC RLYB212 16 M
Slide 12: SC RLYB212 Was Well Tolerated
SC RLYB212 Was Well Tolerated No reports of: • Related or possibly related AEs • Severe or serious AEs AE, adverse event; SC, subcutaneous.
Slide 13: Conclusions
Conclusions SC RLYB212 treatment rapidly and completely eliminated HPA-1a positive platelets in HPA-1a negative subjects in a concentration-dependent manner Both doses of SC RLYB212 met the prespecified proof-of-concept criteria of ≥90% mean reduction in platelet elimination half-life Platelet elimi
Slide 14: Acknowledgments
Acknowledgments • We thank the subjects, study coordinators, and support staff who contributed to this study • The authors thank Iyshwarya Balasubramanian, PhD, of Chameleon Communications International, for providing medical writing assistance, which was funded by Rallybio IPA, LLC • This study was