The risk of early and late cytomegalovirus DNAemia associated with Campath use in stem cell transplant recipients

The risks associated with in vivo and ex vivo use of Campath-1H and -1G in a cohort of 206 stem cell transplant recipients for cytomegalovirus (HCMV) DNAemia have been quantified. DNAemia showed a biphasic incidence pattern with an inflexion at day 60. The first phase had a linear risk rate for HCMV DNAemia of 0.3 % day(−1) whilst the second phase had a substantially lower risk rate of 0.058 % day(−1). In multivariable analyses, risk factors for early DNAemia were HCMV serostatus, radiotherapy based conditioning and CD34 stem cell dose, with the use of in vivo Campath-1H having the most significant risk (Hazards Ratio = 3.68 (95% CI 2.02-6.72; p<0.001). Ex vivo use of Campath was not associated with an increased risk for HCMV DNAemia. Patients receiving either in vivo Campath-1H or -1G experienced HCMV DNAemia earlier (27 and 33 days respectively) compared to patients receiving no Campath (time to DNAemia, 51 days; p = 0.0006). Multivariable analysis of risk factors for HCMV DNAemia occurring beyond 100 days after transplant were older age, acute GVHD > grade II and a lower CD34 stem cell dose whereas Campath-1H use was not associated with late HCMV DNAemia.