title: Long-term follow-up of study participants from prophylactic HIV vaccine clinical trials in Africa.
abstract: Long-term safety is critical for the development and later use of a vaccine to prevent HIV/AIDS. Likewise, the persistence of vaccine-induced antibodies and their impact on HIV testing must be established. IAVI has sponsored several Phase I and IIA HIV vaccine trials enrolling healthy, HIV-seronegative African volunteers. Plasmid DNA and viral vector based vaccines were tested. No vaccine-related serious adverse events were reported. After completion of vaccine trials conducted between 2001-2007, both vaccine and placebo recipients were offered enrolment into an observational long-term follow-up study (LTFU) to monitor potential late health effects and persistence of immune responses. At scheduled 6-monthly clinic visits, a health questionnaire was administered; clinical events were recorded and graded for severity. Blood was drawn for HIV testing and cellular immune assays. 287 volunteers were enrolled; total follow-up after last vaccination was 1463 person years (median: 5.2 years). Ninety-three (93)% of volunteers reported good health at their last LTFU visit. Infectious diseases and injuries accounted for almost 50% of the 175 reported clinical events, of which over 95% were mild or moderate in severity. There were 30 six pregnancies, six incident HIV infections and 14 volunteers reported cases of social harm. Persistence of immune responses was rare. No safety signal was identified. No potentially vaccine-related medical condition, no immune mediated disease, or malignancy was reported. HIV vaccines studied in these trials had a low potential of induction of persisting HIV antibodies.
authors.affiliation: International AIDS Vaccine Initiative (IAVI); NY, NY USA.
authors.forename: Claudia
authors.initials: C
authors.lastname: Schmidt
authors.affiliation: Kenya AIDS Vaccine Initiative (KAVI); University of Nairobi, Kenya.
authors.forename: Walter
authors.initials: W
authors.lastname: Jaoko
authors.affiliation: Kenya AIDS Vaccine Initiative (KAVI); University of Nairobi, Kenya.
authors.forename: Gloria
authors.initials: G
authors.lastname: Omosa-Manyonyi
authors.affiliation: UVRI-IAVI HIV Vaccine Program; Entebbe, Uganda.
authors.forename: Pontiano
authors.initials: P
authors.lastname: Kaleebu
authors.affiliation: UVRI-IAVI HIV Vaccine Program; Entebbe, Uganda.
authors.forename: Juliet
authors.initials: J
authors.lastname: Mpendo
authors.affiliation: UVRI-IAVI HIV Vaccine Program; Entebbe, Uganda.
authors.forename: Annet
authors.initials: A
authors.lastname: Nanvubya
authors.affiliation: Projet San Francisco (PSF); Kigali, Rwanda.
authors.forename: Etienne
authors.initials: E
authors.lastname: Karita
authors.affiliation: Projet San Francisco (PSF); Kigali, Rwanda.
authors.forename: Roger
authors.initials: R
authors.lastname: Bayingana
authors.affiliation: Desmond Tutu HIV Center (DTHC); Cape Town, South Africa.
authors.forename: Linda-Gail
authors.initials: LG
authors.lastname: Bekker
authors.affiliation: Zambia Emory HIV Research Program (ZEHRP); Lusaka, Zambia.
authors.forename: Elwyn
authors.initials: E
authors.lastname: Chomba
authors.affiliation: Zambia Emory HIV Research Program (ZEHRP); Lusaka, Zambia.
authors.forename: William
authors.initials: W
authors.lastname: Kilembe
authors.affiliation: Department of Medical Microbiology; University of Limpopo, Medunsa Campus; Pretoria, South Africa.
authors.forename: Maphoshane
authors.initials: M
authors.lastname: Nchabeleng
authors.affiliation: Projet San Francisco (PSF); Kigali, Rwanda.
authors.forename: Julien
authors.initials: J
authors.lastname: Nyombayire
authors.affiliation: IAVI; Clinical (Immunology) Laboratory; Parktown, South Africa.
authors.forename: Gwynn
authors.initials: G
authors.lastname: Stevens
authors.affiliation: IAVI; Clinical (Immunology) Laboratory; Parktown, South Africa.
authors.forename: Paramesh
authors.initials: P
authors.lastname: Chetty
authors.affiliation: International AIDS Vaccine Initiative (IAVI); NY, NY USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lehrman
authors.affiliation: IAVI; Human Immunology Laboratory (HIL); Imperial College; London, UK.
authors.forename: Josephine
authors.initials: J
authors.lastname: Cox
authors.affiliation: Emory University; Atlanta, GA USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Allen
authors.affiliation: EMMES: The EMMES Corporation; Rockville, MD USA.
authors.forename: Len
authors.initials: L
authors.lastname: Dally
authors.affiliation: EMMES: The EMMES Corporation; Rockville, MD USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Smith
authors.affiliation: International AIDS Vaccine Initiative (IAVI); NY, NY USA.
authors.forename: Patricia E
authors.initials: PE
authors.lastname: Fast
mesh_terms: D016915:AIDS Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000349:Africa / Q000453:epidemiology; D002986:Clinical Trials as Topic; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000453:epidemiology* / Q000517:prevention & control*; D006304:Health Status; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D016915:AIDS Vaccines
keywords: Africa; HIV vaccine trials; healthy adult volunteers; long term follow-up; safety