Combination antiviral and anti-CMV immunoglobulin therapy for CMV infection: A case-control study

Background Intravenous hyper-immune anti-cytomegalovirus immunoglobulins (CMV-IG) therapy are licensed for prophylaxis, yet their therapeutic value in established CMV disease remains poorly defined. We aimed to evaluate the clinical and virological impact of adjunctive CMV-IG in combination with standard antiviral therapy in immunocompromised patients with CMV disease, compared with standard antiviral therapy alone. Methods We performed a single-center retrospective case-control study at A.O.U. “Federico II” University Hospital, Naples, Italy, including consecutive immunocompromised patients with CMV disease between March 2021 and November 2024. Cases received standard antiviral therapy plus CMV-IG (100 IU kg-1 day-1 for three consecutive days). Controls received antivirals only. Results Thirty-four patients were analyzed (15 cases, 19 controls). Thirty-day survival was 93% vs 95% (p=>0.9) and composite outcome (combination of 30-day mortality and clinical response) occurred in 93% vs 90% (p=>0.9) in cases and controls, respectively. Median time-to-virological response in days was achieved 4 vs 7 days (p=<0.001), as was median duration of antiviral therapy in days 12 vs 16 days (p=0.001) and hospitalization 14 vs 19 days (p=0.004) in cases and controls, respectively. Adverse-event rates were low and comparable in the 2 groups. Conclusions In this real-world cohort, adjunctive CMV-IG did not affect mortality, but was associated with faster virological clearance and shorter antiviral and hospital courses, without additional toxicity.