Press release

Investor Relations

Joshua Murray

ir@orcabio .com

Orca Bio to Present at the 41st Annual J.P. Morgan Healthcare Conference

MENLO PARK, CA, Jan. 6, 2023 – Orca Bio, a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, genetic blood disorders and autoimmune diseases, today announced that Ivan Dimov, Ph.D., Orca Bio’s co-founder and chief executive officer, will present at the 41st Annual J.P. Morgan Healthcare Conference.

The company presentation will take place on Monday, January 9, 2023, at 7:30 AM PST at the Westin St. Francis in the Mission Bay Room on the 32nd floor.

About Orca Bio

Contact:

Corporate Communications

Investor Relations

Joshua Murray

Orca Bio Presents Positive Data Reinforcing Clinical Profile of Orca-T and Orca-Q at 2023 Transplantation & Cellular Therapy Meetings of ASTCT and CIBMTR

Three oral presentations showcase clinical evidence for Orca Bio’s promising pipeline of early- and late-stage high-precision cell therapies

Orca-T demonstrated high relapse-free survival in recipients with fully matched donors and early potential in patients with mismatched donors

Orca-Q showed improved graft-versus-host disease-free, relapse-free survival in patients with haploidentical donors

MENLO PARK, CA, February 16, 2023 – Orca Bio, a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, genetic blood disorders and autoimmune diseases, today announced data from the company’s investigational high-precision cell therapy programs, Orca-T and Orca-Q, were presented in three oral presentations at the 2023 Transplantation & Cellular Therapy Meetings of ASTCT and CIBMTR.

Positive data on Orca-T was presented from the single-center Phase 2 and multi-center Phase 1b trials of patients with acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), myelodysplastic syndromes (MDS) and other hematological malignancies. Outcomes with Orca-T appeared to be further enhanced in patients who received a conditioning regimen of busulfan, fludarabine and thiotepa (BFT). At 12 months, the 71 patients in the Orca-T BFT subgroup reported no non-relapse mortality (0%), and high rates of relapse-free survival (87%), graft-versus-host disease-free, relapse-free survival (GRFS) (81%) and overall survival (94%). These data were previously presented at the 64th American Society of Hematology (ASH) Annual Meeting in December 2022.

In a second oral presentation, new data highlighted how expanding the donor pool may help address disparities in access to transplant. Today, approximately 70% of blood cancer patients do not have access to a fully matched related donor, and the likelihood of a patient finding a matched unrelated donor in the U.S. is as low as 29% for some ethnic backgrounds. While the use of human leukocyte antigen (HLA) mismatched donors has increased access to treatment for these patients undergoing allogeneic hematopoietic stem cell transplant (alloHSCT), clinical outcomes have also been associated with significantly worse overall survival, disease-free survival, treatment-related mortality and acute graft versus host disease (aGvHD). In a small cohort (n=8), Orca-T demonstrated promising results in patients with HLA mismatched (7/8) donors, including no cases of severe GvHD or non-relapse mortality and 100% overall survival to date. While this early data is encouraging, more studies of Orca-T in this patient population are ongoing and will provide additional clinical data in this setting.

"As we continue to enroll patients in our pivotal Phase 3 trial of Orca-T, we are extremely encouraged by its continued potential to improve relapse-free and overall survival rates,” said Ivan Dimov, Ph.D., co-founder and chief executive officer of Orca Bio. “Beyond its promise to enhance outcomes and reduce deadly, transplant-related risks, this early evidence that Orca-T may improve clinical outcomes in patients who can’t find a fully matched donor is an important step toward our ultimate goal of offering a safe and effective treatment to all patients who may benefit.”

Orca Bio also presented findings from a Phase 1 multi-center trial of its second investigational cell therapy, Orca-Q, showing that patients with haploidentical – or half-matched – allogeneic hematopoietic stem cell donors, experienced no moderate-to-severe chronic GvHD (0%) and an improved GRFS rate (75%). Orca-Q is a proprietary composition of enriched CD34+ stem cells combined with specific T cell subsets derived from haploidentical donors. Unlike standard of care haploidentical alloHSCT, Orca-Q does not require post-transplant cyclophosphamide (PTCy). These data were also previously presented at the ASH Annual Meeting.

“A haploidentical stem cell transplant is currently the only curative treatment option available for the majority of blood cancer patients who lack a matched donor, but providers often find themselves balancing the risk of relapse and the risk of debilitating side effects like GvHD, infections and other toxicities,” said Samer Srour, M.D., Department of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center. “These interim findings show patients treated with Orca-Q experienced improved outcomes with significantly fewer transplant-related toxicities, suggesting this novel cell therapy could help to address this critical unmet medical need.”

Links to the abstracts follow:

Oral Presentation Title: Precision-Engineered Cell Therapy Orca-T Demonstrates High Relapse-Free Survival at 1 Year While Reducing Graft-Versus-Host Disease and Toxicity

Oral Presentation Title: Orca-T, a High-Precision Cell Therapy, for the Treatment of Hematologic Malignancies in Patients with 7/8 Mismatch Donors

Oral Presentation Title: Orca-Q Demonstrates Favorable GvHD-and-Relapse-Free Survival with Haploidentical Donors without Post-Transplant Cyclophosphamide

Poster Presentation Title: Estimating the Current and Future Costs and Health Outcomes of Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplantation (Allo-HCT)

About Orca-T

Orca-T is an investigational high-precision allogeneic cell therapy consisting of infusions containing regulatory T cells, conventional T cells and CD34+ stem cells derived from peripheral blood from either related or unrelated matched donors. Orca-T has received Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration and is being studied to treat multiple hematological malignancies.

About Orca-Q

Orca-Q is Orca Bio’s second investigational high-precision allogeneic cell therapy to enter clinical development for hematological malignancies. Orca-Q is a proprietary composition of enriched CD34+ stem cells combined with specific T cell subsets derived from haploidentical donors that are purified through Orca Bio’s high-precision platform. Orca-Q is a therapy that has the potential to improve patient outcomes and reduce the risks of graft versus host disease, without the use of post-transplant cyclophosphamide (PTCy) in patients for whom a full human leukocyte antigen (HLA) match cannot be found.

About Orca Bio

Orca Bio is a late-stage biotechnology company developing purified, high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders. Our investigational therapies are designed to deliver better survival rates with dramatically fewer risks than standard allogeneic stem cell transplants, like graft versus host disease and other debilitating transplant-related toxicities. At Orca Bio, we hope to not only replace patients' blood and immune systems with healthy ones, but restore their quality of life. For more information, visit www.orcabio.com and follow Orca Bio on Twitter: @OrcaBio.

Contact:

Corporate Communications

Kelsey Grossman

Investor Relations

Joshua Murray

Orca Bio to Present Positive Clinical Data on its Novel High-Precision Cell Therapies at the 65th American Society of Hematology Annual Meeting

The first oral presentation will demonstrate the performance of Orca-T in patients over 55 years of age compared with younger patients

A second oral presentation will highlight Orca-Q, Orca Bio’s high-precision cell therapy for patients with haploidentical donors

Additional poster presentations include outcomes in patients with high-risk myelodysplastic syndrome treated with Orca-T and results of Orca-T in patients undergoing reduced intensity conditioning

MENLO PARK, CA, November 2, 2023 – Orca Bio, a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders, today announced that new data will be presented at the American Society of Hematology (ASH) Annual Meeting from December 9-12 in San Diego, CA. Specifically, an oral presentation will highlight the outcomes of myeloablative Orca-T, Orca Bio’s lead investigational high-precision cell therapy, in patients over the age of 55. A second oral presentation will share updated results in an expanded group of patients with haploidentical donors treated with Orca Bio’s second investigational high-precision cell therapy, Orca-Q.

Orca Bio will also present two posters highlighting the results of patients with high-risk myelodysplastic syndrome who were treated with Orca-T, and the outcomes of patients treated with Orca-T who received reduced intensity conditioning.

The ASH abstracts are now available at www.hematology.org. Details of the Orca Bio presentations follow:

Oral Session: 721. Allogeneic Transplantation: Conditioning Regimens, Engraftment and Acute Toxicities: Optimizing Conditioning Regimens for Lymphoid Malignancies and Fanconi Anemia

Title: Optimizing Outcomes with Myeloablative Conditioning in Older Patients: Efficacy and Safety of Precision Engineered Orca-T in Patients > 55 Years Old with Hematologic Malignancies

Abstract Number: 230

Date and Time: Saturday, December 9, 2023 at 2:15 PM PT

Location: Marriott Marquis, Marriott Grand Ballroom 5-6

Oral Session: 704. Cellular Immunotherapies: Early Phase and Investigational Therapies: Novel Approaches to Enhance Cellular Therapies and Immune Responses in Leukemias and Lymphomas

Title: Safety and Efficacy of Orca-Q with Haploidentical Donors for the Treatment of Advanced Hematologic Malignancies Without the Use of Post-Transplant Cyclophosphamide

Abstract Number: 773

Date and Time: Monday, December 11, 2023 at 11:30 AM PT

Location: San Diego Convention Center, Room 6CF

Poster Session: 732. Allogeneic Transplantation: Disease Response and Comparative Treatment Studies

Title: High Disease-Free Survival in Patients with High-Risk MDS Treated with Orca-T

Abstract Number: 2230

Date and Time: Saturday, December 9, 2023 at 5:30 PM PT

Location: San Diego Convention Center, Halls G-H

Poster Session: 722. Allogeneic Transplantation: Acute and Chronic GVHD, Immune Reconstitution

Title: Phase 1 Trial Results for Patients with Advanced Hematologic Malignancies Undergoing Reduced Intensity Allogeneic HCT with Orca-T Donor Cell Therapy Product and Single Agent Tacrolimus

Abstract Number: 3560

Date and Time: Sunday, December 10, 2023 at 6:00 PM PT

Location: San Diego Convention Center, Halls G-H

About Orca-T

Orca-T is an investigational high-precision allogeneic cell therapy for the treatment of multiple hematological malignancies. Orca-T includes infusions containing regulatory T-cells, CD34+ stem cells and conventional T-cells derived from peripheral blood from either related or unrelated matched donors. Orca-T is currently being evaluated in a pivotal Phase 3 clinical trial at leading transplant centers across the U.S. and has received Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration.

About Orca-Q

Orca-Q is an investigational high-precision allogeneic cell therapy designed to treat hematological malignancies in patients with haploidentical donors. Orca-Q is a proprietary composition of stem cells combined with specific T-cell subsets derived from healthy donors and engineered by Orca Bio’s high-precision platform. Orca-Q has the potential to improve patient outcomes and reduce the risks of toxicities without the use of post-transplant cyclophosphamide (PTCy) in patients unable to identify a full human leukocyte antigen (HLA) match.

About Orca Bio

Orca Bio is a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders. Our investigational products are designed to safely replace a patient’s diseased blood and immune system with a healthy one, delivering significantly better outcomes with dramatically fewer risks than the standard of care. Our manufacturing platform uses single-cell precision to create proprietary, uniquely-defined products that have the potential to transform allogeneic cell therapy. At Orca Bio, our mission is to make curative cell therapies both more effective and safer, and in doing so, push past the field’s current boundaries and redefine its future. For more information, visit www.orcabio.com and follow Orca Bio on Twitter: @OrcaBio.

Contact:

Corporate Communications

Kelsey Grossman

Investor Relations

Joshua Murray

Orca Bio to Present Positive Clinical Outcomes with Orca-T in Patients with AML at 2024 ASCO Annual Meeting

Relapse-free survival and overall survival were 82.5% and 100% at 12 months, respectively, in 37 patients with AML, an aggressive form of blood cancer

Non-relapse mortality at 12 months was 0%

Orca-T is currently being evaluated in a pivotal Phase 3 clinical trial at leading treatment centers across the U.S.

MENLO PARK, CA, May 23, 2024 – Orca Bio, a biotechnology company committed to transforming the lives of patients through high-precision cell therapy, today announced it will present new data at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois, from May 31–June 4. The presentation will highlight outcomes of its lead investigational allogeneic T-cell immunotherapy, Orca-T, in patients with acute myeloid leukemia (AML).

AML is an aggressive form of blood cancer and the most common acute leukemia in adults. There are an estimated 20,800 new diagnoses and nearly 11,200 deaths in the U.S. each year.

“Today, only a fraction of adults diagnosed with AML undergo curative treatment with standard of care allogeneic hematopoietic stem cell transplant due to the serious and life-threatening risks often associated with it,” said Rawan Faramand, M.D., assistant member of Blood and Marrow Transplant and Cellular Immunotherapy at Moffitt Cancer Center. “These new findings suggest Orca-T has the potential to offer a cure with low rates of treatment-related mortality, and could provide an important option for patients with AML. With its goal of alleviating the tradeoff between the risk of relapse and the risk of toxicities observed with standard of care stem cell transplant, this novel approach has the potential to expand curative treatment to many more patients.”

A new subanalysis from the ongoing multi-center Phase 1b single-arm trial evaluated outcomes with Orca-T among a subgroup of 37 patients with AML who had a median age of 51 years and median follow-up of 14 months. All patients received myeloablative conditioning (MAC) with busulfan, fludarabine and thiotepa (BFT), followed by Orca-T and single-agent graft versus host disease (GvHD) prophylaxis with tacrolimus. At 12 months, results found relapse-free survival was 82.5% (95% CI: 65.0, 91.7) and non-relapse mortality was 0%. Overall survival was 100% (95% CI: 100, 100) at 12 months. The safety profile of Orca-T in this subgroup was consistent with the larger Phase 1b population with no new safety signals identified. Across all patients, Orca-T was manufactured reliably and delivered with vein-to-vein times of 72 hours or less across the U.S.

“We’re pleased to present at ASCO for the first time and share the latest findings that support the potential for Orca-T to offer a curative solution and fulfill a significant unmet need for patients with AML,” said Scott McClellan, M.D., Ph.D., chief medical officer at Orca Bio. “These data continue to advance our mission of expanding potentially life-saving treatment to patients and their providers who face limited viable options today.”

Details of the Orca Bio presentation follow:

Title: Treatment of Acute Myeloid Leukemia with Orca-T

Session: Hematologic Malignancies—Leukemia, Myelodysplastic Syndromes, and Allotransplant

Abstract Number: 6552

Poster Code: 111

Date and Time: June 3, 2024, from 9AM - 12PM CDT

Location: Oncology Professionals Hall

The ASCO abstracts are available at https://conferences.asco.org/am/abstracts.

About Orca-T

Orca-T is an investigational allogeneic T-cell immunotherapy being evaluated in clinical trials for the treatment of multiple hematologic malignancies. Orca-T is comprised of highly purified regulatory T-cells, CD34+ stem cells and conventional T-cells derived from peripheral blood from either related or unrelated matched donors. Orca-T is currently being evaluated in a pivotal Phase 3 clinical trial at leading transplant centers across the U.S. and has received Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration.

About Orca Bio

Contact:

Corporate Communications

Kelsey Grossman

Investor Relations

Joshua Murray

ASH abstracts are now available at www.hematology.org. Details of the Orca Bio presentations follow:.

Orca Bio to Present Four Abstracts at the 64th American Society of Hematology Annual Meeting, Including Updated Relapse-Free Survival Data with Orca-T and the First Clinical Data for Orca-Q

Oral presentation to highlight impressive results with Orca-T on relapse-free survival (RFS) at one year in the Phase 1b/2 clinical trials

Oral presentation will detail first data readout of Orca-Q in haploidentical allogeneic transplant demonstrating favorable graft-versus-host disease and relapse-free survival (GRFS) at one year in patients with hematologic malignancies

Poster presentation will demonstrate the mechanism of action of Orca-T for blood and immune reconstitution

Poster presentation to show the health economic benefit to the US healthcare system of doubling the number of patients able to achieve GRFS

MENLO PARK, CA, November 3, 2022 – Orca Bio, a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, genetic blood disorders and autoimmune diseases, today announced that new clinical data will be presented at the American Society of Hematology (ASH) Annual Meeting from December 10-13. Specifically, an oral presentation will include new data on relapse-free survival with Orca Bio’s lead investigational high-precision cell therapy, Orca-T. Additionally, results from Orca Bio’s Phase 1 clinical trial of its second investigational cell therapy, Orca-Q, in patients with haploidentical donors will be presented for the first time in an oral presentation.

Orca Bio will also share two poster presentations featuring data on immune reconstitution and elevated regulatory T cell frequencies in patients treated with Orca-T, as well as an analysis of the cost burden of allogeneic hematopoietic cell transplants and the potential value of addressing this unmet need.

Oral presentations:

Title: Precision-Engineered Cell Therapy Orca-T Demonstrates High Relapse-Free Survival at 1 Year While Reducing Graft-Versus-Host Disease and Toxicity

Abstract Number: 265
Date and time: Saturday, December 10, 2022, at 2 p.m. CST
Location: 391-392, Ernest N. Morial Convention Center

Presenter: Everett Meyer, M.D., Ph.D., Associate Professor of Medicine, Division of Blood and Marrow Transplantation and Cellular Therapy, Stanford Health Care

Title: Orca-Q Demonstrates Favorable GvHD-and Relapse-Free Survival in Haploidentical Transplants without Post-Transplant Cyclophosphamide
Abstract Number: 769

Date and time: Monday, December 12, 2022, at 10:30 a.m. CST
Location: 252-254, Ernest N. Morial Convention Center

Presenter: Amandeep Salhotra, M.D., Associate Professor, Division of Leukemia, Department of Hematology and Hematopoietic Cell Transplantation, City of Hope

Poster Presentations:

Title: Rapid Immune Reconstitution and Elevated Regulatory T Cell Frequencies in Patients Treated with Orca-T
Abstract Number: 3408

Date and time: Sunday, December 11, 2022, from 6 p.m. – 8 p.m. CST
Location: Hall D, Ernest N. Morial Convention Center

Title: Estimating the Lifetime Medical Cost Burden of an Allogeneic Hematopoietic Cell Transplantation Patient and the Value of Addressing the Unmet Need
Abstract Number: 4865

Date and time: Monday, December 12, 2022, from 6 p.m. – 8 p.m. CST
Location: Hall D, Ernest N. Morial Convention Center

About Orca-T

About Orca-Q

Orca-Q is an investigational allogeneic cellular therapy consisting of a single infusion containing a proprietary composition of stem and immune cells derived from peripheral blood from either related or unrelated matched, unmatched or haploidentical donors. Orca-Q is currently being studied to treat multiple hematologic malignancies in alternative donor settings, with and without GvHD prophylaxis.

About Orca Bio

Orca Bio is a clinical-stage biotechnology company developing purified, high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders. Our investigational therapies are designed to deliver better survival rates with dramatically fewer risks than standard allogeneic stem cell transplants, like graft versus host disease and other debilitating transplant-related toxicities. At Orca Bio, we hope to not only replace patients' blood and immune systems with healthy ones, but restore their quality of life. For more information, visit www.orcabio.com and follow Orca Bio on Twitter: @orcabio.

Contact

Corporate Communications

Investor Relations

Joshua Murray

Orca Bio Presents Clinical Results on Use of Orca-Q without GvHD Prophylaxis in Patients with Hematological Malignancies at the 66th ASH Annual Meeting

Orca Bio Presents Clinical Results on Use of Orca-Q® without GvHD Prophylaxis in Patients with Hematological Malignancies at the 66th ASH Annual Meeting

Orca-Q allogeneic T-cell immunotherapy with no GvHD prophylaxis in patients with matched donors demonstrated low rates of GvHD and non-relapse mortality

MENLO PARK, CA, December 7, 2024 – Orca Bio, a late-stage biotechnology company committed to transforming the lives of patients through high-precision cell therapy, today presented clinical findings on the use of Orca-Q, its investigational second-generation allogeneic T-cell immunotherapy, without the use of any graft versus host disease (GvHD) prophylaxis in patients with diverse hematological conditions at the 66th American Society of Hematology (ASH) Annual Meeting.

Preliminary data from a subset of the multicenter Phase 1 clinical trial of Orca-Q in patients with acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myeloid leukemia (CML) and myelofibrosis (MF) showed encouraging patient outcomes without the use of GvHD prophylaxis, including low rates of GvHD, infection and non-relapse mortality (NRM) in patients with fully matched donors.

“With a conventional allogeneic stem cell transplant, patients typically receive a mix of strong immunosuppressive drugs to control GvHD. These can also lead to poor immune reconstitution and increase the risk of infections, organ damage and relapse,” said presenting author Mehrdad Abedi, MD, hematologist and professor of Medicine at UC Davis Comprehensive Cancer Center. “The possibility of achieving a cure without the need for preventative agents could expand the treatment landscape for patients with hematologic malignancies. While additional data is needed, these early findings suggest Orca-Q without GvHD prophylaxis may have the potential to transform our treatment approach.”

This analysis evaluated 14 patients enrolled in the HLA-identical donor dose expansion arm who received myeloablative conditioning (MAC) with Orca-Q and either busulfan, fludarabine and thiotepa (BFT) or total body irradiation-based conditioning (TBI). Across all patients, the median time to engraftment of neutrophils and platelets was 11 days and rates of GvHD and serious infections were low. In the subgroup of patients who received Orca-Q and BFT, there was no chronic GvHD of any grade and two cases of grade 2 acute GvHD. There were no cases of non-relapse mortality (NRM) reported across all 14 patients. Relapse-free survival (RFS) and overall survival (OS) were both 85% among all patients, and both 90% in the BFT population. GvHD-free, relapse-free survival (GRFS) was 77% and 90% across all patients and in the BFT group, respectively.

Across all patients, Orca-Q was manufactured reliably and delivered with vein-to-vein times of 72 hours or less across the U.S.

“Our team is inspired by the possibility of developing a product that could eliminate the need for GvHD prophylaxis while preserving safety and efficacy, a concept representing a significant advancement for hematology and beyond,” said Nate Fernhoff, PhD, co-founder and chief scientific officer at Orca Bio. “We are highly encouraged by these preliminary data which provide an early glimpse into the future therapeutic potential of Orca-Q.”

About Orca-Q

Orca-Q is Orca Bio’s second-generation investigational allogeneic T-cell immunotherapy being evaluated in clinical trials for the treatment of multiple hematologic malignancies, including in patients with haploidentical donors. Orca-Q is a proprietary composition of stem cells combined with specific T-cell subsets derived from healthy donors and engineered by Orca Bio’s high-precision platform.

About Orca Bio

Orca Bio is a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer and autoimmune diseases. Our investigational products are designed to replace a patient’s diseased blood and immune system with a healthy one, with the goal of improving outcomes with fewer risks than the standard of care. Our manufacturing platform uses single-cell precision to create proprietary, uniquely-defined products that have the potential to transform allogeneic cell therapy. At Orca Bio, our mission is to make curative cell therapies both more effective and safer, and in doing so, push past the field’s current boundaries and redefine its future. For more information, visit www.orcabio.com.

Contact:

Corporate Communications

Kelsey Grossman

Investor Relations

Joshua Murray

Orca Bio Presents Positive Data Demonstrating the Potential for Orca-T and Orca-Q to Expand Treatment to Additional Patient Groups at the 65th ASH Annual Meeting

Orca-T, Orca Bio’s lead investigational high-precision cell therapy, showed similar results in older patients undergoing myeloablative conditioning as seen in younger patients across disease control, non-relapse mortality and overall survival

Orca-T in older patients given a reduced intensity conditioning regimen demonstrated curative potential with no incidence of relapse and encouraging relapse-free survival

Orca-T showed positive results in patients with intermediate to high-risk myelodysplastic syndrome

Orca-Q, Orca Bio’s second investigational high-precision cell therapy, showed encouraging data in graft-versus-host-disease-free and relapse-free survival in patients with a haploidentical donor without the use of post-transplant cyclophosphamide

MENLO PARK, CA, Dec. 9, 2023 – Orca Bio, a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders, today announced positive new data that suggest its investigational high-precision cell therapies, Orca-T and Orca-Q, have the potential to deliver improved clinical outcomes across different age ranges, donor types and conditioning regimens relative to existing standard of care allogeneic hematopoietic stem cell transplants (alloHSCT). The results presented at the 65th American Society of Hematology (ASH) Annual Meeting showed promising data with the use of Orca Bio’s cell therapies across several patient groups where there is significant unmet medical need.

Orca-T in Older Patients with Myeloablative Conditioning

Results highlighted in an oral presentation showed Orca-T’s ability to deliver similar outcomes in older patients undergoing myeloablative conditioning (MAC) as younger patients. Notably, Orca-T delivered similar results across disease control, non-relapse mortality (NRM) and overall survival (OS).

“While the use of MAC offers the best chance of a cure, it also increases life-threatening complications in older patients receiving standard of care alloHSCT,” said presenting author Caspian Oliai, M.D., medical director of the UCLA Bone Marrow Transplantation Stem Cell Processing Center. “These latest findings suggest a cell therapy like Orca-T, which has the potential to offer a cure while reducing toxicity and lowering treatment-related mortality, may allow older patients to better tolerate MAC. This approach could expand curative treatment to older patients who might not be offered a MAC regimen today, and potentially provide physicians with an important new option in our ongoing efforts to balance the risk of relapse with transplant-related side effects.”

In a subgroup analysis, 64 patients from Orca Bio’s ongoing multi-center Phase 1b clinical trial who received Orca-T and busulfan, fludarabine and thiotepa (BFT) conditioning for the treatment of acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), mixed phenotype leukemia, chronic myeloid leukemia (CML) and myelodysplastic syndromes (MDS) were divided into two age groups: 18-54 years of age (n=39), and 55 years of age and older (n=25). With a median follow-up of 12 months, the following outcomes were reported:

Relapse-free survival (RFS) was 84.8% in younger patients and 82.3% in older patients.
NRM was 0% in both groups.
OS was 100% and 95.5% in the younger and older patient groups, respectively.
Events of grade 3-4 acute graft versus host disease (GvHD) and moderate-to-severe chronic GvHD were low across the younger group (0 and 3, respectively) and older group (1 and 3, respectively).

Across all patients, Orca-T continued to be manufactured reliably and delivered with vein-to-vein times of 72 hours or less across the U.S.

Orca-T in Older Patients with Reduced Intensity Conditioning

Additional data from a single-center open-label Phase 1 clinical trial presented at ASH looked at the outcomes of older patients treated with Orca-T and a reduced intensity conditioning (RIC). These patients were found to be unfit for a MAC regimen due to the significant risks associated with it, particularly in older age. At 12 months, patients treated with a RIC Orca-T (n=15) saw no observable compromise in curative outcomes, with no patients experiencing relapse (0%). Patients also saw encouraging RFS (79%) and a low incidence of both grade 3-4 acute and chronic GvHD (0% and 7%, respectively).

Collectively, these findings support the potential for Orca-T to treat older patients with hematological malignancies, whether they are given a MAC or RIC regimen, with no new safety signals reported.

Orca-T in Patients with MDS

New data was also presented on the performance of Orca-T in patients with intermediate to high-risk MDS. Current treatments for MDS aren’t often curative, and many patients relapse or become resistant to first-line treatment. There remains an unmet need for new, more effective but tolerable strategies to manage MDS.

In this subgroup from the ongoing multi-center Phase 1b clinical trial, Orca-T demonstrated promising results in this patient population (n=16). At one year, RFS with Orca-T was 94%. No patients experienced grade 3-4 acute GvHD, and moderate-to-severe chronic GvHD occurred in two patients. The rates of NRM and OS with Orca-T were 0% and 94%, respectively.

Orca-T is currently being evaluated in a pivotal Phase 3 clinical study for the treatment of AML, ALL and MDS at leading transplant centers across the U.S.

Orca-Q for Patients with Haploidentical Donors

In an oral presentation, Orca Bio shared updated data from a multi-center Phase 1 clinical trial of its second high-precision cell therapy, Orca-Q, in patients with a haploidentical donor without the use of post-transplant cyclophosphamide (PTCy).

“Orca-Q is a first-in-class therapy that has the potential to improve patient outcomes and reduce the risk of graft versus host disease without the use of PTCy,” said presenting author Samer Srour, M.D., M.S., Department of Stem Cell Transplantation and Cellular Therapy at The University of Texas MD Anderson Cancer Center. “While PTCy has increased the use of haploidentical HSCTs, it can bring a myriad of risks and toxicities that we didn’t experience with Orca-Q. These updated results in an expanded group of patients continue to support Orca-Q’s promise to overcome the challenges of haploidentical stem cell transplant by providing a solution where patients and physicians may no longer have to compromise between the risk of relapse and the risk of GvHD.”

The positive outcomes from an expanded group of 33 patients with AML, ALL and CML support Orca-Q as a potential treatment option for patients with a haploidentical donor. With a median of 375 days follow-up, updated safety and efficacy data include:

No patients experienced moderate-to-severe chronic GvHD (0%).
There was one event of grade 3 acute GvHD and no grade 4 acute GvHD.
NRM was 9%.
RFS, GRFS and OS at one year were 82%.

Additionally, no new safety signals were identified. The estimated incidence of CTCAE grade 2 and greater than grade 3 infections at one year were 9% and 15%, respectively.

“At Orca Bio, we understand the challenges providers face in achieving the right balance in offering blood cancer patients the best option for a cure with optimal quality of life,” said Ivan Dimov, Ph.D., co-founder and chief executive officer of Orca Bio. “We are pleased to present these latest findings at ASH that add to our growing body of clinical evidence which underscore the potential of our novel high-precision platform to expand potentially life-saving treatment to more patient groups who could benefit.”

The full ASH presentations will be made available on www.orcabio.com.

About Orca-T

Orca-T is an investigational high-precision allogeneic cell therapy being evaluated in clinical trials for the treatment of multiple hematologic malignancies. Orca-T includes infusions containing regulatory T-cells, CD34+ stem cells and conventional T-cells derived from peripheral blood from either related or unrelated matched donors. Orca-T is currently being evaluated in a pivotal Phase 3 clinical trial at leading transplant centers across the U.S. and has received Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration.

About Orca-Q

Orca-Q is an investigational high-precision allogeneic cell therapy being evaluated in clinical trials for the treatment of hematologic malignancies in patients with haploidentical donors. Orca-Q is a proprietary composition of stem cells combined with specific T-cell subsets derived from healthy donors and engineered by Orca Bio’s high-precision platform. Orca-Q has the potential to improve patient outcomes and reduce the risks of toxicities without the use of post-transplant cyclophosphamide (PTCy) in patients unable to identify a full human leukocyte antigen (HLA) match.

About Orca Bio

Orca Bio is a late-stage biotechnology company developing high-precision cell therapies for the treatment of cancer, autoimmune diseases and genetic blood disorders. Our investigational products are designed to safely replace a patient’s diseased blood and immune system with a healthy one, delivering significantly better outcomes with dramatically fewer risks than the standard of care. Our manufacturing platform uses single-cell precision to create proprietary, uniquely-defined products that have the potential to transform allogeneic cell therapy. At Orca Bio, our mission is to make curative cell therapies both more effective and safer, and in doing so, push past the field’s current boundaries and redefine its future. For more information, visit www.orcabio.com and follow Orca Bio on Twitter: @OrcaBio.

Contact:

Corporate Communications

Kelsey Grossman

Investor Relations

Joshua Murray

ir@orcabio .com