Outcomes with nivolumab maintenance after autologous hematopoietic stem cell transplantation in relapsed/refractory Hodgkin lymphoma: A systematic review and meta-analysis.

Abstract

e19037 Background: Hodgkin Lymphoma (HL) patients undergoing autologous stem cell transplantation (auto-SCT) remain at high risk for relapse, necessitating effective maintenance strategies. Nivolumab, a PD-1 checkpoint inhibitor, has shown promise in reducing relapse rates and maintaining disease control in HL. This meta-analysis evaluates the efficacy and safety of nivolumab maintenance after auto-SCT in HL. Methods: A literature search was performed on PubMed, Cochrane, and ClinicalTrials.gov using relevant keywords and MeSH terms following PRISMA guidelines. Fifty-nine results were screened, and five studies reporting outcomes of nivolumab maintenance after auto-SCT in adult HL patients were included. Proportions and corresponding 95% confidence intervals (CI) were calculated using the inverse variance method applied to Freeman-Tukey double arcsine transformed data. Statistical analyses were conducted using R version 4.4.0 and the "meta" and "metasens" packages. Results: A total of 358 patients from 5 studies (1 pilot trial, 2 Phase II trials, and 2 retrospective studies) were analyzed. The age range was 18–72 years, with 59% male. Most patients had stage 4 (59%) followed by stage 3 (19%) HL, and had received 3–15 prior lines of therapy. Nivolumab maintenance was given for 2-72 weeks. The median follow-up period was 14.5 months (range: 6–60). The pooled overall survival (OS) was 98% (95% CI: 0.93–1.00, I² = 14%, p = 0.32, n = 351), 94% (95% CI: 0.84–0.99, I² = 8%, p = 0.34, n = 271), and 94% (95% CI: 0.71–1.00, I² = 20%, p = 0.29, n = 259) at 6, 12, and 24 months, and progression-free survival (PFS) was 76% (95% CI: 0.65–0.86, I² = 47%, p = 0.13, n = 351), 74% (95% CI: 0.04–1.00, I² = 85%, p < 0.01, n = 271), and 73% (95% CI: 0.0–1.00, I² = 95%, p < 0.01, n = 252) at 6, 12, and 24 months, respectively. The overall response rate (ORR) was 83% (95% CI: 0.64–0.97, I² = 64%, p = 0.03, n = 358), with a complete response (CR) of 39% (95% CI: 0.09–0.73, I² = 81%, p < 0.01, n = 358), and a partial response (PR) of 41% (95% CI: 0.09–0.78, I² = 75%, p < 0.01, n = 358). 16% (95% CI: 0.03–0.37, I² = 54%, p = 0.11, n = 332) had stable disease, while 13% (95% CI: 0.0–0.53, I² = 77%, p < 0.01, n = 339) exhibited disease progression. The pooled mortality was 9% (95% CI: 0.0–0.29, I² = 77%, p < 0.01, n = 72) and disease progression (53%) followed by graft-versus-host disease (11%) were the most common causes of death. The most frequently reported treatment-related adverse events included fatigue (25%), infusion-related reactions (16%), rash (13%), nausea (11%), and pruritus (10%). Conclusions: Nivolumab maintenance demonstrates good efficacy in HL patients post-auto-SCT, with a manageable toxicity profile. However, the limited sample size and lack of randomized controlled trials warrant a cautious interpretation of these results and highlight the need for future research to validate these findings.