Where could vaccine trials in IDU be done?
In addition to Bangkok, where there is hard evidence that IDU can be enrolled and retained, there are several other IDU cohorts which could participate in future trials. Also in Thailand, a cohort in Chiang Mai supported by the National Institute of Drug Abuse (NIDA, the NIH institute focused primarily on substance abuse), led by David Celentano and Vinai Suriyanon, found a high, steady seroincidence among 400 IDU of 7.7/100PY (95% confidence interval 5.0-10.4) despite risk reduction counseling, condom promotion, and training in safe injection practices. Virtually all newly infected IDU in this cohort have the same HIV subtype E found in cohorts at sexual risk in Chiang Mai. Several sites are now being built up in China. The HVTN is supporting a site in Guangxi Province (southern China) together with the HIV Prevention Trials Network (HPTN), which also works in Xinjiang, in China’s far northwest. Both sites are involved in HPTN 039, a cohort development study aimed at assessing retenti
