The present invention relates to formulations of nucleotide reverse transcriptase inhibitors (NRTIs), preferably [2-(6-Amino-pur: in-9-yl)-1-methyl-ethoxymethy]-phosphonic acid (tenofivir, PMPA), or a physiologically functional derivative thereof, wherein the formulations contain a low level of glycerin. Human immunodeficiency vims (HIV) infection and related diseases are a major public health problem worldwide. One approach to the problem of HIV/AIDS is to reduce the risk of transmission of HIV and thus reduce the number of individuals who become newly infected.