The HIV-1 epidemic remains unchecked despite existing technology; vaccines and 
microbicides in development may help reverse the epidemic. Reverse transcriptase 
inhibitors (RTIs) formulated in gels tenofovir (TFV) and IVRs (dapivirine) are 
under clinical development. While TFV or similar products may prove successful 
for HIV-1, alternatives to RTIs may provide additional benefits, e.g., broader 
STI prevention. Biopharmaceutical agents under development as microbicides 
include cyanovirin, RANTES analogues, commensals, and Mabs. Cost of 
manufacturing biopharmaceuticals has been reduced and they can be formulated 
into tablets, films, and IVRs for vaginal delivery. Nanotechnology offers a 
novel approach to formulate microbicides potentially leading to uniform 
epithelial delivery. Delivery through vaginal mucus may be possible by 
controlling nanoparticle size and surface characteristics. Combining prevention 
modalities may be the most effective means of preventing STI transmission, 
importantly, codelivery of microbicides and vaccines has demonstrated. Finally, 
the safety of microbicide preparations and excipients commonly used can be 
assessed using a mouse/HSV-2 susceptibility model. Screening of new microbicide 
candidates and formulation excipients may avoid past issues of enhancing HIV-1 
transmission. This article forms part of a special supplement covering several 
presentations on novel microbicide formulations from the symposium on "Recent 
Trends in Microbicide Formulations" held on 25 and 26 January 2010, Arlington, 
VA.