TScan Therapeutics Completes Enrollment in Cohort C of Phase 1 ALLOHA™ Trial and Announces FDA Clearance of Investigational New Drug Applications for Heme Candidates TSC-102-A01 and TSC-102-A03

Completed enrollment of Cohort C in the Phase 1 ALLOHA™ trial; patients to be treated with commercial-ready manufacturing process

Received FDA clearance of INDs for TSC-102-A01 and TSC-102-A03 targeting CD45, for patients with HLA types A01:01 and A03:01

Plans to initiate Phase 1 study of both TSC-102 candidates in the second half of 2026

WALTHAM, Mass., Feb. 26, 2026 (GLOBE NEWSWIRE) -- TScan Therapeutics, Inc. (Nasdaq: TCRX), a clinical-stage biotechnology company focused on the development of T cell receptor (TCR)-engineered T cell (TCR-T) therapies for the treatment of patients with cancer, today announced completion of enrollment into Cohort C of the ALLOHA™study. Patients in Cohort C are being treated using the new commercial-ready manufacturing process. The Company also announced that the U.S. Food and Drug Administration (FDA) has cleared its investigational new drug (IND) applications for TSC-102-A01 and TSC-102-A03 for patients with HLA types A01:01 and A03:01, respectively.

“We are excited about the potential of TSC-101 to treat residual disease and prevent relapse in patients undergoing hematopoietic cell transplantation,” said Gavin MacBeath, Ph.D., Chief Executive Officer. “We have now enrolled over ten patients in Cohort C of the ALLOHA™study where we are treating patients with our new commercial-ready manufacturing process. We look forward to sharing data from this cohort in the second quarter of this year, prior to launching our Phase 3 study. We are also pleased to announce that the FDA has cleared our IND applications for TSC-102-A01 and TSC-102-A03, and we look forward to initiating a Phase 1 trial with these candidates in the second half of this year. We believe the addition of these product candidates will nearly double the addressable U.S. patient population in our heme program.”

“During the Tandem Meetings of ASTCT and CIBMTR, we highlighted the relationship between donor chimerism and long-term outcomes in patients following HCT,” added Chrystal U. Louis, M.D., Chief Medical Officer. “Specifically, patients that achieved complete donor chimerism by month two after transplant using a high-sensitivity assay have a significantly lower probability of relapse (HR=4.6, p=0.02) compared to those who did not achieve complete donor chimerism. We look forward to sharing early chimerism data from Cohort C and formally initiating our pivotal study for TSC-101.”

The Phase 1 ALLOHA™study is evaluating TSC-101 in A*02:01-positive patients with heme malignancies undergoing allogeneic hematopoietic cell transplantation (allo-HCT). TScan plans to share safety and early chimerism data from Cohort C in the second quarter of 2026. The Company also plans to launch a pivotal trial for TSC-101 in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) in the second quarter of 2026.

The U.S. FDA clearance of INDs for TSC-102-A01 and TSC-102-A03 continues the momentum in TScan’s heme program by expanding HLA coverage to include patients who are HLA-A01:01-positive or HLA-A03:01-positive, respectively. These TCR-T therapy candidates target CD45, a protein broadly expressed in heme cells but absent in non-heme tissues.

TScan plans to initiate a Phase 1 trial for both TSC-102-A01 and TSC-102-A03 in the second half of 2026. Products will be manufactured using the commercial-ready process and will enroll patients with various hematologic malignancies undergoing allo-HCT using either reduced intensity conditioning or myeloablative conditioning. The multi-center Phase 1 trial is designed to assess safety and initial efficacy of these TCR-T therapy candidates.

TScan is a clinical-stage biotechnology company focused on the development of T cell receptor (TCR)-engineered T cell (TCR-T) therapies for the treatment of patients with cancer. The Company’s lead TCR-T therapy candidate is in development for the treatment of patients with hematologic malignancies to prevent relapse following allogeneic hematopoietic cell transplantation (the ALLOHA™Phase 1 heme trial). The Company has developed multiple TCR-T therapy candidates for solid tumors and is currently developing methods forin vivoengineering using these candidates. The Company is also applying their target discovery platform to discover novel targets in various T cell-mediated autoimmune disorders.

This release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding the Company’s plans, progress, expectations, and timing relating to the Company’s hematologic malignancies program, including the number and dosing of patients using the commercial-ready manufacturing process; clinical updates and presentation of data for the Phase 1 ALLOHA™trial; clinical trial design and initiation of a pivotal trial for TSC-101; initiation of Phase 1 trial for both TSC-102 candidates; the progress of the hematologic malignancies program being indicative or predictive of the success of such program; the Company’s current and future research and development plans or expectations; the structure, timing and success of the Company’s planned preclinical development, submission of INDs, clinical trials, and commercial opportunity including addressable market; the potential benefits of any of the Company’s proprietary platforms or current or future product candidates in treating patients; and the Company’s goals and strategy. TScan intends such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 21E of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by terms such as, but not limited to, “may,” “might,” “will,” “objective,” “intend,” “should,” “could,” “can,” “would,” “expect,” “believe,” “anticipate,” “project,” “target,” “design,” “estimate,” “predict,” “potential,” “plan,” “on track,” or similar expressions or the negative of those terms. Such forward-looking statements are based upon current expectations that involve risks, changes in circumstances, assumptions, and uncertainties. The express or implied forward-looking statements included in this release are only predictions and are subject to a number of risks, uncertainties and assumptions, including, without limitation: the beneficial characteristics, safety, efficacy, therapeutic effects and potential advantages of TScan’s TCR-T therapy product candidates; TScan’s expectations regarding its preclinical studies being predictive of clinical trial results; TScan’s approved INDs being indicative or predictive of bringing TScan closer to its goal of providing customized TCR-T therapies to treat patients with cancer; the timing of the launch, initiation, progress, expected results and announcements of TScan’s preclinical studies, clinical trials and its research and development programs; TScan’s ability to enroll patients for its clinical trials within its expected timeline; TScan’s plans relating to developing and commercializing its TCR-T therapy product candidates, if approved, including sales strategy; estimates of the size of the addressable market for TScan’s TCR-T therapy product candidates; TScan’s manufacturing capabilities and the scalable nature of its manufacturing process; TScan’s estimates regarding expenses, future milestone payments and revenue, capital requirements and needs for additional financing; TScan’s expectations regarding competition; TScan’s anticipated growth strategies; TScan’s ability to attract or retain key personnel; TScan’s ability to establish and maintain development partnerships and collaborations; TScan’s expectations regarding federal, state and foreign regulatory requirements; TScan’s ability to obtain and maintain intellectual property protection for its proprietary platform technology and our product candidates; the sufficiency of TScan’s existing capital resources to fund its future operating expenses and capital expenditure requirements; and other factors that are described in the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of TScan’s most recent Annual Report on Form 10-K and any other filings that TScan has made or may make with the SEC in the future. Any forward-looking statements contained in this release represent TScan’s views only as of the date hereof and should not be relied upon as representing its views as of any subsequent date. Except as required by law, TScan explicitly disclaims any obligation to update any forward-looking statements.