BACKGROUND: The present review is part of the ESCMID Study Group for Infections 
in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and 
biological therapies.
AIMS: To review, from an Infectious Diseases perspective, the safety profile of 
agents targeting CD19, CD20 and CD52 and to suggest preventive recommendations.
SOURCES: Computer-based MEDLINE searches with MeSH terms pertaining to each 
agent or therapeutic family.
CONTENT: Although CD19-targeted agents (blinatumomab or inebilizumab) are not 
associated with an increased risk of infection, they may cause IgG 
hypogammaglobulinaemia and neutropenia. The requirement for prolonged 
intravenous infusion of blinatumomab may increase the risk of 
catheter-associated bloodstream infections. Infection remains the most common 
non-haematological adverse effect of anti-CD20 monoclonal antibodies, including 
severe respiratory tract infection, hepatitis B virus (HBV) reactivation and 
varicella-zoster virus infection. Screening for chronic or resolved HBV 
infection is recommended for patients receiving anti-CD20 monoclonal antibodies. 
Antiviral prophylaxis should be offered for 12-18 months to hepatitis B surface 
antigen (HBsAg)-positive and HBsAg-negative/anti-hepatitis B core antibody 
(HBc)-positive patients. Anti-Pneumocystis prophylaxis should be considered in 
patients receiving concomitant chemotherapy, particularly steroids. Alemtuzumab 
(anti-CD52) increases the risk of infections, in particular among leukaemia and 
solid organ transplant patients. These populations benefit from 
anti-Pneumocystis prophylaxis, prevention strategies for cytomegalovirus 
infection, and screening for HBV, hepatitis C virus and tuberculosis. Antiviral 
prophylaxis for at least 6-12 months should be provided for HBsAg-positive 
patients.
IMPLICATIONS: As there are limited clinical data for many of the reviewed 
agents, special attention must be given to promptly detect and report emerging 
infectious complications.