CLINICAL IMMUNOGENICITY AND TOLERANCE STUDIES OF LIQUID VACCINES DELIVERED BY JET-INJECTOR AND A NEW SINGLE-USE CARTRIDGE (IMULE(R)) - COMPARISON WITH STANDARD SYRINGE INJECTION

A new needleless jet-injector, Mini-Imojet(R), was developed that admi nisters liquid vaccines from a single-use, pre-filled cartridge named Imule(R), which avoids the risk of cross-contamination. We conducted c linical trials in several settings in France and West Africa to compar e the immunogenicity and tolerance of five vaccines (influenza vaccine , Vi capsular polysaccharide typhoid vaccine, tetanus toroid vaccine, diphtheria-tetanus-whole cell pertussis vaccine, and inactivated hepat itis A vaccine) administered with the Imule(R) system vs standard syri nge technique. In each vaccine study, all subjects of either group wer e tested for serum antibody titres to calculate the geometrical mean t itres and seroconversion rates after complete vaccination. Immediate l ocal reactions were noted after each injection, and local and general reactions were evaluated during a predetermined period of follow-up. W hen delivered by the Imule(R) technique, all the administrated vaccine s were of equivalent or superior immunogenicity, compared to the syrin ge technique. The tolerance to vaccines injected by the Imule(R) syste m was acceptable in all studies. The most frequently observed reaction s were mild (e.g. minor bleeding, superficial papules, erythema and in duration) and could be considered to be inherent to the injection tech nique. The technical and safety advantages of the Mini-Imojet(R)/Imule (R) system, compared to sterilizable, standard disposable or autodestr uct syringes and to classical multi-dose vial jet-injectors, reinforce s the interest of this new injection technique for collective immuniza tions. (C) 1997 Elsevier Science Ltd.