Therapeutic antibodies for infectious diseases

Perspectives Passive immunization is the transfer of antibodies and occurs naturally during pregnancy. The transplacental transfer of maternal antibodies to the fetus can protect the infant from many infectious diseases for the first vulnerable months of its life. Passive immunization has been used in the global effort to eliminate maternal and neonatal tetanus. Researchers have estimated that vaccinating pregnant women with two or more doses of tetanus-containing vaccine has reduced neonatal mortality from tetanus by 94%. 1 In addition, clinicians have used passive immunization, to prevent or to treat various infections for over a century for diseases such as rabies, diphtheria , tetanus, hepatitis B, respiratory syncytial virus and botulism. Passive immunization is also used in immuno-compromised individuals and to manage complications after vaccination. Most of the antibody preparations administered to patients, containing polyclonal antibodies, have been derived from sera of immunized animals, immunized humans, and for some rarer diseases, from sera of convalescent patients. 2–4 Box 1 presents blood-derived polyclonal antibodies currently in use. The production and use of polyclonal antibodies have revealed several challenges, including standardization, patient safety, supply and access. These challenges have led researchers to explore the possibility of replacing polyclonal antibodies with monoclonal antibodies (mAbs), which can be produced through recombinant deoxyribonucleic acid technologies. In the past, producing mAbs was difficult and expensive. However, the increasing use of mAbs as therapeutics for cancer, autoimmune diseases and other chronic diseases has led to increased production capacities and improved manufacturing processes. 8 These advancements have made mAbs potentially cost-competitive with blood-derived polyclonal antibod-ies, while at the same time contributing towards an improved supply at a global level. Over 40 therapeutic mAbs are currently in use, targeting a range of noncommunicable diseases. In addition to potentially addressing the patient safety and supply limitations of polyclonal antibodies, anti-infective mAbs may offer prophylactic or therapeutic interventions for infectious diseases where drugs or vaccines are not available or are poorly efficacious. For example, the use of broadly cross-reactive mAbs to prevent influenza or neutralizing mAbs against Ebola and Middle East respiratory syndrome coro-navirus (MERS-CoV). Furthermore, anti-infective mAbs could be used to target multidrug resistant pathogens, such as Staphylococcus aureus, to reduce the incidence of hospital-acquired infections and may help to prevent the emergence of antimicrobial resistance. Although passive immunization produces a short-lived protection against infections, mAbs have some advantages over vaccines for active immunization. First, protection from vaccination takes longer and …