Photo Credit: Tiratus Phaesuwan

 Anti-T-lymphocyte globulin significantly reduced the risk of GvHD, relapse, or death by 48%, enhancing GRFS, especially in matched donor transplants.

Acute and chronic graft-versus-host disease (GvHD) are critical complications of allogeneic hematopoietic cell transplantation (alloHCT). Myelofibrosis, a myeloproliferative neoplasm, presents with symptoms such as splenomegaly and anemia. Researchers investigated the role of anti-T-lymphocyte globulin (ATLG) as GvHD prophylaxis in patients with myelofibrosis undergoing their first alloHCT.

AlloHCT is the only curative treatment, but it carries risks, including GvHD, especially in older patients. The conditioning regimen often includes T-cell depletion with ATLG to prevent GvHD.

The study analyzed data from 707 patients, comparing outcomes between those who received ATLG (n=469) and those who did not (n=238). Results, which were published online in Bone Marrow Transplantation, showed a significant reduction in the incidence of acute GvHD (grade II-IV) in the ATLG group (30%) compared to the non-ATLG group (56%, P<0.001). Similarly, severe acute GvHD (grade III-IV) was less frequent in the ATLG group (20% vs 25%, P=0.01). Although the incidence of chronic GvHD was similar between both groups, severe chronic GvHD was significantly lower in the ATLG group (7% vs 18%, P=0.04). GvHD-free and relapse-free survival (GRFS) at six years was higher in the ATLG group (45% vs 37%, P=0.02), with ATLG showing benefits, particularly in matched-related and unrelated donor settings.

The study’s multivariable analysis indicated that ATLG’s positive impact on GRFS was independent of HLA-match. While ATLG significantly reduced acute GvHD, it did not affect chronic GvHD incidence. The findings align with other studies showing ATLG’s effectiveness in reducing GvHD in various transplant settings, although this study specifically focused on myelofibrosis. The study also highlighted that ATLG did not increase relapse rates, which contrasts with some previous studies. The findings underscore the importance of optimal conditioning regimens and donor selection to improve transplant outcomes.

The authors confirmed that ATLG significantly reduced the risk of GvHD, relapse, or death by 48%, enhancing GRFS, especially in matched donor transplants. There were no significant differences in relapse risk, non-relapse mortality, or overall survival between the ATLG and non-ATLG groups.

Despite limitations, such as the retrospective nature and potential selection bias, the study provides robust evidence supporting ATLG’s use in myelofibrosis patients undergoing alloHCT. The significant reduction in acute GvHD with ATLG use and the improved GRFS suggest ATLG is a valuable prophylactic agent in this context. The study calls for further research to refine conditioning regimens and GvHD prophylaxis strategies to enhance transplant success rates in myelofibrosis.