Accession Number : ADA552928


Title :   Safety and Immunogenicity of a Shigella flexneri 2a Invaplex 50 Intranasal Vaccine in Adult Volunteers


Descriptive Note : Journal article


Corporate Author : NAVAL MEDICAL RESEARCH CENTER SILVER SPRING MD


Personal Author(s) : Tribble, D ; Kaminski, R ; Cantrell, J ; Nelson, M ; Porter, C ; Baqar, S ; Williams, C ; Arora, R ; Saunders, J ; Ananthakrishnan, M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a552928.pdf


Report Date : Jun 2010


Pagination or Media Count : 11


Abstract : Shigellosis is a leading cause of diarrhea worldwide prompting vaccine development The Shigella flexneri lnvaplex 50 is a macromolecular complex containing lpaB, lpaC, and LPS, formulated from an aqueous extract of virulent Shigella delivered via nasal administration. Preclinical vaccine testing demonstrated safety, immunogenicity and efficacy. An open-label dose-escalating phase 1 study evaluated a 3-dose (2-week intervals) regimen via nasal pipette delivery. Thirty-two subjects were enrolled into one of four vaccine dose groups ( 10, 50, 240, or 480 micrograms). The vaccine was well tolerated with minor short-lived nasal symptoms without evidence of dose effect. Antibody-secreting cell (ASC) responses were elicited at doses equal 50 micrograms with the highest lgG ASC, Invaplex 50 (100%) and S.flexneri 2a LPS (71%), as well as. serologic responses (43%) occurring with the 240 micrograms dose. FecallgA responses, Invaplex 50 (38.5%) and LPS (30.8%) were observed at doses =240 micrograms. The lnvaplex 50 nasal vaccine was safe with encouraging mucosal immune responses. Follow-on studies will optimize dose, delivery mechanism and assess efficacy in aS. flexneri 2a challenge study.


Descriptors :   *DIARRHEA , *IMMUNOGENS , *INFECTIOUS DISEASES , *SHIGELLA FLEXNERI , *VACCINES , CLINICAL MEDICINE , DOSAGE , IMMUNITY , MACROMOLECULES , MUCOUS MEMBRANES , RESPONSE(BIOLOGY) , SEROLOGY , SHIGELLA , SHIGELLOSIS , TEST AND EVALUATION


Subject Categories : Medicine and Medical Research
      Microbiology


Distribution Statement : APPROVED FOR PUBLIC RELEASE