Surveillance of transmitted drug resistance to integrase inhibitors in Spain: implications for clinical practice.

BACKGROUND: Integrase strand-transfer inhibitors (INSTIs) constitute at present one of the pillars of first-line ART. OBJECTIVES: To study the prevalence of and the trend in transmitted drug resistance (TDR) to INSTIs in ART-naive patients in Spain. METHODS: During the period 2012-17, 1109 patients from CoRIS were analysed. The Stanford algorithm v8.7 was used to evaluate TDR and transmission of clinically relevant resistance. To describe individual mutations/polymorphisms, the most recent IAS list (for INSTIs) and the 2009 WHO list update (for the backbone NRTIs used in combination with INSTIs in first-line treatment) were used. RESULTS: Clinically relevant resistance to the INSTI class was 0.2%: T66I, 0.1%, resistance to elvitegravir and intermediate resistance to raltegravir; and G163K, 0.1%, intermediate resistance to raltegravir and elvitegravir. No clinical resistance to dolutegravir or bictegravir was observed. The prevalence of INSTI TDR following the IAS-USA INSTI mutation list was 2.6%, with no trend towards changes in the prevalence throughout the study period. The overall prevalence of NRTI WHO mutations was 4.3%, whereas clinically relevant resistance to tenofovir, abacavir and emtricitabine/lamivudine was 1.7%, 1.9% and 0.7%, respectively. CONCLUSIONS: Given the low prevalence of clinically relevant resistance to INSTIs and first-line NRTIs in Spain, it is very unlikely that a newly diagnosed patient will present with clinical resistance to a first-line INSTI-based regimen. These patients may not benefit from INSTI and NRTI baseline resistance testing.

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions.

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41-6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain. Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000-2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively. Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2-79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999-2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin. Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics.