Encouraging New Data: Grafalon Benefits High-Risk Pediatric HSCT Patients in the FORUM Study

Encouraging New Data: Grafalon Benefits High-Risk Pediatric HSCT Patients in the FORUM Study Rapperswil, Switzerland, April 28, 2026 - Neovii Pharmaceuticals AG today announced new findings from the large, prospective randomized phase 3 international FORUM study (ALL SCTped 2012), evaluating treatment outcomes associated with different serotherapy approaches in pediatric patients undergoing matched unrelated donor allogeneic hematopoietic stem cell transplantation (HSCT).

The international, prospective FORUM study evaluated outcomes in children and young adults aged ≤21 years with acute lymphoblastic leukemia (ALL) undergoing a first allogeneic hematopoietic stem cell transplantation (HSCT) from a 9/10 or 10/10 HLA‑matched unrelated donor. The study compared two rabbit anti‑thymocyte globulins: the Neovii medicine Grafalon^® (anti‑T‑lymphocyte globulin, ATLG) and anti-Thymocyte Globulin (ATG) in combination with different conditioning regimens to reduce the risks of graft‑versus‑host disease (GvHD). Outcomes from more than 1,100 pediatric and young adult patients were included, providing a robust clinical basis for comparative evaluation across predefined risk groups.

Cohort 1 (patients aged ≥4 years receiving TBI‑based conditioning) In the overall cohort of patients aged ≥4 years receiving total body irradiation (TBI)–based conditioning, survival outcomes were generally comparable between the two serotherapy preparations. However, statistically significant differences emerged in clinically relevant subgroups and endpoints favoring Grafalon.

• GvHD and infection outcomes: In the overall ≥4‑year TBI cohort, treatment with Grafalon was associated with a statistically significant reduction in chronic GvHD (p=0.015) and a significant reduction in viral infections, including CMV and EBV (p<0.001). Non‑relapse mortality (NRM) was numerically lower after Grafalon.
• PBSC graft recipients (higher‑risk subgroup for acute and chronic GVHD): Among patients aged ≥4 years receiving peripheral blood stem cell (PBSC) grafts, Grafalon demonstrated statistically superior outcomes. Grafalon was associated with a significantly lower 3‑year non‑relapse mortality (6% vs 25%; p=0.001) and significantly higher overall survival (p=0.012) and event‑free survival (p=0.022). These survival advantages were accompanied by a significantly lower incidence of severe viral infections.

Cohort 2 (children aged below 4 years receiving chemotherapy‑based conditioning) In younger children conditioned with chemotherapy, outcomes differed by serotherapy, with Grafalon demonstrating statistically significant benefit in key efficacy endpoints.

• ATLG (Grafalon) was associated with a significantly higher 3‑year event‑free survival (59% vs 37%; p=0.029) compared with anti-Thymocyte Globulin (ATG).
• Multivariate analysis confirmed ATLG (Grafalon) as an independent factor associated with improved event‑free survival in this cohort (HR 0.54; p=0.046).
• Non‑relapse mortality was low in both serotherapy groups; relapse rates showed a numerical reduction after Grafalon, consistent with the observed improvement in event‑free survival.

Cohort 3 (children aged above 4 years receiving chemotherapy-based conditioning), no statistical differences could be observed.

These new findings add to a growing body of clinical and translational evidence supporting the value of ATLG in the HSCT setting, and Neovii intends to interact with the relevant regulatory authorities to seek approval for the use of Grafalon in pediatric patients.

The FORUM study is a prospective, randomized, investigator-initiated trial (IIT) supported by academic institutions, Neovii, and other industry partners. Between 2012 and 2026, more than 2,000 patients were enrolled across 32 countries on five continents and treated according to risk- and age-stratified protocols. The study is now being followed by FORUM 2, which aims to further optimize and harmonize the management of HSCT in pediatric ALL, with the goal of reducing complications and improving survival outcomes.

Christina Peters, Professor of Pediatrics at the Department of Stem Cell Transplantation, St. Anna Children's Hospital, Vienna, Principal Investigator of the FORUM study, commented: “The FORUM study was driven by a shared goal: to spare children and adolescents with high-risk acute lymphoblastic leukemia from the burden of total body irradiation (TBI), offering instead the hope of effective treatment with high-dose chemotherapy before allogeneic hematopoietic stem cell transplantation. Bringing together more than 100 centers across Europe, North and South America, Australia, and the Middle East, the study stands as a powerful example of what can be achieved when the global scientific community unites—transcending borders to improve and save young lives. Against all expectations, total body irradiation (TBI) proved to be significantly superior across all primary endpoints, leading to randomization stop. The study continued favoring TBI, with recruitment concluding earlier this year. For me, these results underscore the importance of prospective clinical research—not only in the short term, but in following patients over the long term. It also shows how open exchange and collaboration between experienced and emerging centers can directly translate into better outcomes for our patients. In this new analysis, differences were observed in predefined higher-risk subgroups, including PBSC graft recipients and younger children receiving chemotherapy-based conditioning, where ATLG (Grafalon) was associated with higher survival and lower infection rates as well as lower non-relapse mortality. These findings may help further tailor treatment recommendations for young patients with high-risk leukemia.”

Frederic Prince, Chief Executive Officer of Neovii Pharmaceuticals AG, added: " We are grateful to the FORUM study group investigators, participating centers, and the patients and families whose commitment made this important study possible. Children undergoing stem cell transplantation remain among the most vulnerable patient populations, and the data generated by investigator‑initiated studies such as FORUM provide essential insights to help improve outcomes in this challenging setting. At Neovii we are committed to support and generating robust clinical data while supporting the continued development of Grafalon beyond transplantation — including the ongoing European Phase 2 study in Type 1 Diabetes and planned expansion to the United States as a registrational study under an accelerated approval pathway. In parallel, we are evaluating options to establish additional production capabilities to ensure supply resilience and meet anticipated future needs."

The FORUM study results (Abstract Paed3-01) were presented at the 52nd Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT) in Madrid.

About Grafalon^®

Grafalon^® (anti‑T‑lymphocyte globulin, ATLG) is a polyclonal antibody therapy developed by Neovii and used in organ and stem cell transplantation. The therapy is designed to selectively deplete T lymphocytes and modulate immune responses to help reduce the risk of graft‑versus‑host disease (GvHD) and graft rejection. Grafalon is approved in multiple countries for transplant-related indications; with approved uses varying by country. These indications include the prevention of acute transplant rejection following solid organ transplantation when used in combination with other immunosuppressive medicines, the treatment of acute steroid-resistant transplant rejection, and the prevention of graft-versus-host-disease (GvHD) in patients undergoing allogeneic stem cell transplantation. Grafalon has established clinical use with thousands of patients treated across different transplant settings. Grafalon is an important component of transplant protocols for patients with malignant and non‑malignant hematologic diseases. Neovii continues to make Grafalon available in accordance with its approved indications and applicable local regulatory requirements.

About Neovii Pharmaceuticals AG

Neovii Pharmaceuticals AG is a global, fully integrated, commercial-stage biopharmaceutical company focused on antibody-based immunotherapies. Headquartered in Switzerland, Neovii has more than three decades of experience in the development, manufacturing, and commercialization of polyclonal antibody therapies and operates a dedicated biotech manufacturing facility in the Munich area. The company employs approximately 200 people and commercializes its products in more than 50 countries worldwide.

Neovii has established a strong position in specialized stem cell and solid organ transplant centers. Building on its established transplantation franchise, the company is advancing a strategic expansion into immune-mediated diseases, including an ongoing European randomized, double-blind, placebo-controlled Phase 2 study in Type 1 Diabetes.

Legal Disclaimer

These findings are based on comparative analyses of outcomes among participants in the international FORUM study who received different serotherapy approaches as part of matched unrelated donor allogeneic hematopoietic stem cell transplantation (HSCT). The analyses were exploratory in nature and focused on predefined patient subgroups; further analyses and additional studies may be required to confirm these observations across different clinical settings, conditioning regimens, and patient populations.

Grafalon^® is approved for transplant-related indications in multiple countries; however, its use in pediatric acute lymphoblastic leukemia (ALL) is investigational and not approved in most countries. Nothing in this release should be interpreted as promoting the use of Grafalon for any unapproved indication.