With the persistent challenges towards controlling the HIV epidemic, there is an ongoing need for research
into HIV vaccines and drugs. Sub-Saharan African countries - worst affected by the HIV pandemic - have participated in the
conduct of clinical trials for HIV vaccines. In Kenya, the Kenya AIDS Vaccine Initiative (KAVI) at the University of Nairobi has
conducted HIV vaccine clinical trials since 2001.
Participants were recruited after an extensive informed consent process followed by screening to determine
eligibility. Screening included an assessment of risk behavior, medical history and physical examination, and if clinically
healthy, laboratory testing. In the absence of locally derived laboratory reference ranges, the ranges used in these trials were
derived from populations in the West.
Two hundred eighty-one participants were screened between 2003 and 2006 for two clinical trials. Of
these, 167 (59.4%) met the inclusion/exclusion criteria. Overall, laboratory abnormalities based on the non-indigenous
laboratory references used were the most frequent reasons (61.4%) for ineligibility. Medical abnormalities contributed 30.7%
of the total reasons for ineligibility. Based on the laboratory reference intervals now developed from East and Southern
Africa, those ineligible due to laboratory abnormalities would have been 46.3%. Of the eligible participants, 18.6% declined
Participant recruitment for HIV vaccine clinical trials is a rigorous and time-consuming exercise. Over 61% of
the screening exclusions in clinically healthy people were due to laboratory abnormalities. It is essential that laboratory
reference ranges generated from local populations for laboratory values be used in the conduct of clinical trials to avoid
unnecessary exclusion of willing participants and to avoid over-reporting of adverse events for enrolled participants.
Protocol IAVI VRC V001 . ClinicalTrials.gov NCT00124007 Protocol IAVI 010 
ClincalTrials.gov is in progress)
Protocols IAVI 002 and IAVI 004 are Phase 1 trials only mentioned in introductory
paragraphs; details will not be reported. Registration was not required when they were conducted