Recent trends and patterns in HIV-1 transmitted drug resistance in the United Kingdom.

Objectives Transmission of drug-resistant HIV-1 has decreased in the UK since the early 2000s. This analysis reports recent trends and characteristics of transmitted drug resistance ( TDR) in the UK from 2010 to 2013. Methods Resistance tests conducted in antiretroviral treatment ( ART)-naïve individuals between 2010 and 2013 were analysed for the presence of transmitted drug resistance mutations ( TDRMs), defined as any mutations from a modified 2009 World Health Organization surveillance list, or a modified 2013 International Antiviral Society- USA list for integrase tests. Logistic regression was used to examine associations between demographics and the prevalence of TDRMs. Results TDRMs were observed in 1223 (7.5%) of 16 425 individuals; prevalence declined from 8.1% in 2010 to 6.6% in 2013 ( P = 0.02). The prevalence of TDRMs was higher among men who have sex with men ( MSM) compared with heterosexual men and women (8.7% versus 6.4%, respectively) with a trend for decreasing TDRMs among MSM ( P = 0.008) driven by a reduction in nucleoside reverse transcriptase inhibitor ( NRTI)-related mutations. The most frequently detected TDRMs were K103N (2.2%), T215 revertants (1.6%), M41L (0.9%) and L90M (0.7%). Predicted phenotypic resistance to first-line ART was highest to the nonnucleoside reverse transcriptase inhibitors ( NNRTIs) rilpivirine and efavirenz (6.2% and 3.4%, respectively) but minimal to NRTIs, including tenofovir, and protease inhibitors ( PIs). No major integrase TDRMs were detected among 101 individuals tested while ART-naïve. Conclusions We observed a decrease in TDRMs in recent years. However, this was confined to the MSM population and rates remained stable in those with heterosexually acquired HIV infection. Resistance to currently recommended first-line ART, including integrase inhibitors, remained reassuringly low. [ABSTRACT FROM AUTHOR]