Decreasing trends of drug resistance and increase of non-B subtypes amongst subjects recently diagnosed as HIV-infected over the period 2004–2012 in the Veneto Region, Italy

Patterns of Transmitted Drug Resistance Mutations and HIV-1 Subtype Dynamics in ART-Naïve Individuals in Veneto, Italy, from 2017 to 2024

This study investigates the prevalence and patterns of transmitted drug resistance mutations (TDRMs) and HIV-1 subtypes among antiretroviral therapy (ART) naïve individuals in Veneto, Italy, from 2017 to 2024. This research aims to understand the dynamic landscape of TDRMs and HIV-1 genetic diversity to inform treatment strategies effectively. We included all adult ART-naïve people with HIV (PWH) from seven infectious disease units in Veneto, Italy. We collected the genotypic resistance testing conducted to predict drug susceptibility and subtype distribution using the Stanford HIVdb algorithm. We included 762 PWH, showing a slight but statistically significant decline in the B subtype among Italian PWH (p = 0.045) and an increase in non-B subtypes among foreigners, though it was not statistically significant (p = 0.333). The most frequent mutations were in Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIs), especially in non-B subtypes, with a notable rise from 10.7% in 2017-2019 to 15.5% in 2020-2024. Notably, TDRMs were consistently detected, highlighting an ongoing challenge despite the stable prevalence observed over the years. In addition, the data revealed a concerning rise in mutations against newer drug classes, such as integrase inhibitors. Conclusively, the study underscores the necessity of continuous surveillance of HIV subtypes and resistance patterns to adapt ART regimens optimally. Despite the stable levels of drug resistance, the emergence of resistance against newer drugs necessitates ongoing vigilance and possible adjustment in treatment protocols to enhance clinical outcomes and manage HIV drug resistance effectively.

Predicting Factors of Plasma HIV RNA Undetectability after Switching to Co-Formulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide in Experienced HIV-1 Patients: A Multicenter Study

Switching to bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) from other antiretroviral regimens is safe and effective for virologically suppressed people living with HIV (PLWH). The term virological suppression includes both low but detectable HIV viremia and undetectable HIV viremia, and the latter is possibly associated with a lower immune activation state. Herein, we describe a 24-month follow-up of experienced PLWH with plasma HIV RNA undetectable or detectable < 50 copies/ml switching to BIC/FTC/TAF. A previous 12-month monitoring was available, and the factors correlated with treatment efficacy. This retrospective multicenter study included PLWH who switched to BIC/FTC/TAF in the period of 2019-2022, and who were HBsAg and HCV RNA negative. The follow-up study times were 6 (T6), 12 (T12), 18 (T18), and 24 (T24) months after the switch (T0). Survival analysis with multiple-failure-per-subject design, Kaplan-Meier survival estimates, multivariate analysis of variance, multilevel linear regression, and a hierarchical ordered logistic model were applied. A total of 329 PLWH had plasma HIV RNA which was either undetectable or detectable at <50 copies/mL at T0, and 197 responded to all inclusion criteria: M/F 140/57; the median CD4+ cell count was 677 cells/mm3; and HIV RNA at T0 was undetectable in 108 patients. Most of the 197 patients (122, 61.9%) were on a previous INSTI-based regimen. HIV RNA undetectability was more frequent at each follow-up point in patients with HIV RNA that was undetectable at T0, and it showed a higher frequency throughout the follow-up period in patients with always-undetectable HIV RNA in the 12 months before the switch. A higher nadir CD4 cell count had a predictive role, and HBcAb positivity had no influence. In conclusion, the switch could be programmed and possibly delayed on a case-by-case basis in order to achieve persistent plasma HIV RNA undetectability. Undiagnosed loss of HBcAb has no detrimental consequences on the response to BIC/FTC/TAF.

Circulating Genotypes of Hepatitis C Virus in Italian Patients before and after the Application of Wider Access Criteria to HCV Treatment

Aims:

The aims of this study were to report a description of the HCV genotype distribution in adult Italians and non-Italians subjects tested in the Microbiology and Virology Unit of the Padova University Hospital from January 2016 (after about one year from the availability of DAAs) to December 2018 and to compare genotype frequencies in the 12-month period before and after the application of the wider access criteria to HCV treatment.

Background:

Hepatitis C virus (HCV) infection is a major health problem, but the availability of direct-acting antivirals (DAAs) has dramatically changed HCV disease natural history because these drugs have excellent tolerability and they can eliminate the virus in almost all treated patients.

Objective:

The objective was to describe the circulating HCV genotypes in high-income countries in order to help health authorities in the future organization of DAAs treatment strategies; this aspect is not limited to drug prescription, but it also includes the identification of infected individuals who are undiagnosed, which is the limiting step to achieve the HCV elimination goal.

Methods:

Adult patients who had HCV genotype performed from 01/01/16 to 31/12/18 in the Microbiology and Virology Unit of the Padova University Hospital were included in the study: the two 12-month periods were April 2016-March 2017 (before period, BEF) and April 2017-March 2018 (after period, AFT).

Results:

Italians were 2168 (91.2%) and non-Italians were 208 (8.8%). Italians median age was 55 years, and females were older. Italians had a lower genotype 1 (p=0.0012) and higher genotype 2 frequencies (p<0.0001) with respect to non-Italians. Most patients aged 38-67 years: Italians were more represented in class age 48-57 years (p=0.0138), 68-77 years (p=0.001) and ≥78 years (p<0.0001); subjects with genotype 3 were the youngest and those with genotype 2 the oldest. Italian patients typed in the AFT and BEF were comparable; only a lower frequency of genotype 1 males and younger age in genotype 3 were found in AFT.

Conclusion:

Italians were older with respect to non-Italians, which implies that a different age based screening program could be applied. Italian genotype 3 subjects represent a cohort to focus on for the risk of therapeutic failure. Patients tested after the extended criteria for HCV treatment were very similar to those tested before, suggesting that HCV burden in Italians is higher than expected.

Transmitted drug resistance mutations and trends of HIV-1 subtypes in treatment-naïve patients: A single-centre experience

OBJECTIVES

Transmitted drug resistance (TDR) and HIV-1 genetic diversity may affect treatment efficacy and clinical outcomes. Here we describe the circulating viral subtypes and estimate the prevalence of drug resistance among antiretroviral therapy (ART)-naïve patients attending Sapienza University Hospital (Rome, Italy) from 2006-2017.

METHODS

Genotypic resistance testing (GRT) was performed on 668 ART-naïve patients for integrase (n = 52), protease and reverse transcriptase (n = 668) sequences.

RESULTS

Twenty-one different HIV-1 subtypes and circulating recombinant forms (CRFs) were identified. Subtype B was the most common (67.1%), followed by CRF02_AG (8.4%), and subtypes C and F (both 6.0%). A significantly increase in the proportion of non-B strains (P < 0.001) and the rate of non-Italian patients was observed over time. The overall prevalence of TDR was 9.4% (NRTI, 4.2%; NNRTI, 5.8%; and PI, 1.0%) and was higher in subtype B strains. Transmitted INSTI mutations (Q148H and G140S) responsible for high-level resistance to raltegravir and elvitegravir and intermediate resistance to dolutegravir and bictegravir were found, for the first time, in two individuals. Minor or accessory INSTI mutations were detected in 17.3% of patients. No significant decrease in the prevalence of TDR was documented over time.

CONCLUSION

The significant increase in non-B subtypes suggests that the molecular epidemiology of HIV-1 is changing. Detection of a major INSTI mutation in two ART-naïve patients highlights the importance of performing GRT before commencing treatment. This finding and the lack of a significant reduction in TDRs underline the importance of continuous surveillance of resistance mutations.

Oral and anal high-risk human papilloma virus infection in HIV-positive men who have sex with men over a 24-month longitudinal study: complexity and vaccine implications

Background

Few studies focused on longitudinal modifications over time of high-risk HPV (HR-HPV) at anal and oral sites in HIV+ men who have sex with men (MSM).

Methods

We described patterns and longitudinal changes of HR-HPV detection and the prevalence of HR-HPV covered by the nonavalent HPV vaccine (vax-HPV) at oral and anal sites in 165 HIV+ MSM followed in an Italian hospital. The samples were collected at baseline and after 24 months (follow-up). The presence of HPV was investigated with Inno-LiPA HPV Genotyping Extra II.

Results

Median age was 44 years (IQR 36–53), median CD4+ cell count at nadir was 312 cells/mm³ (IQR 187–450). A total of 120 subjects (72.7%) were receiving successful antiretroviral therapy (ART). At baseline and follow-up, the frequency of HR-HPV was significantly higher in the anal site (65.4% vs 9.4 and 62.4% vs 6.8%, respectively). Only 2.9% of subjects were persistently HR-HPV negative at both sites. All oral HR-HPV were single at baseline vs 54.6% at baseline at the anal site (p = 0.005), and all oral HR-HPV were single at follow-up vs 54.4% at anal site at follow-up (p = 0.002). The lowest rate of concordance between the oral and anal results was found for HR-HPV detection; almost all HR-HPV positive results at both anal and oral sites had different HR-HPV.The most frequent HR-HPV in anal swabs at baseline and follow-up were HPV-16 and HPV-52.At follow-up at anal site, 37.5% of patients had different HR-HPV genotypes respect to baseline, 28.8% of subjects with 1 HR-HPV at baseline had an increased number of HR-HPV, and patients on ART showed a lower frequency of confirmed anal HR-HPV detection than untreated patients (p = 0.03) over time. Additionally,54.6 and 50.5% of patients had only HR-vax-HPV at anal site at baseline and follow-up, respectively; 15.2% had only HR-vax-HPV at baseline and follow-up.

Conclusions

We believe that it is important testing multiple sites over time in HIV-positive MSM. ART seems to protect men from anal HR-HPV confirmed detection. Vaccination programmes could reduce the number of HR-HPV genotypes at anal site and the risk of the first HR-HPV acquisition at the oral site.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7004-x) contains supplementary material, which is available to authorized users.

Drug resistance in B and non-B subtypes amongst subjects recently diagnosed as primary/recent or chronic HIV-infected over the period 2013-2016: Impact on susceptibility to first-line strategies including integrase strand-transfer inhibitors

OBJECTIVES

To characterize the prevalence of transmitted drug resistance mutations (TDRMs) by plasma analysis of 750 patients at the time of HIV diagnosis from January 1, 2013 to November 16, 2016 in the Veneto region (Italy), where all drugs included in the recommended first line therapies were prescribed, included integrase strand transfer inhibitors (InNSTI).

METHODS

TDRMs were defined according to the Stanford HIV database algorithm.

RESULTS

Subtype B was the most prevalent HIV clade (67.3%). A total of 92 patients (12.3%) were expected to be resistant to one drug at least, most with a single class mutation (60/68-88.2% in subtype B infected subjectsand 23/24-95.8% in non-B subjects) and affecting mainly NNRTIs. No significant differences were observed between the prevalence rates of TDRMs involving one or more drugs, except for the presence of E138A quite only in patients with B subtype and other NNRTI in subjects with non-B infection. The diagnosis of primary/recent infection was made in 73 patients (9.7%): they had almost only TDRMs involving a single class. Resistance to InSTI was studied in 484 subjects (53 with primary-recent infection), one patient had 143C in 2016, a total of thirteen 157Q mutations were detected (only one in primary/recent infection).

CONCLUSIONS

Only one major InSTI-TDRM was identified but monitoring of TDRMs should continue in the light of continuing presence of NNRTI-related mutation amongst newly diagnosed subjects, sometime impacting also to modern NNRTI drugs recommended in first-line therapy.

Trends in drug resistance-associated mutations in a real-life cohort of Italian patients infected with HIV-1

Recent studies support the idea that human immunodeficiency virus type 1 (HIV-1) drug resistance is declining in developed countries. To help assess the current situation in Italy, the dynamics of drug resistance mutations in pol and integrase genes in plasma samples from HIV-1-positive patients attending Sapienza University Hospital, Rome, from 2003 to 2014 were analysed. In total, 1730 genotype resistance tests (GRTs) were retrospectively analysed. The prevalence of major drug resistance mutations (DRMs) was evaluated over time in the global population and in patients with antiretroviral therapy (ART) failure. Population dynamics, changes in ART administration, and HIV-1 RNA levels were analysed in combination with DRM trends. The global population showed a strong reduction in major DRMs to all drug classes. Over the 2003-2014 decade, resistance to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) declined from 80.0% to 18.7%, from 42.8% to 20.1% and from 74.2% to 8.3%, respectively (P<0.005 for all comparisons). However, only PI-associated mutations showed a significant decrease in patients experiencing ART failure. Interestingly, analysis of the integrase gene disclosed an increased resistance to integrase inhibitors, mainly regarding N155H, detected in 32.6% of raltegravir-treated patients in 2012-2014. In conclusion, in line with previous findings, this study shows that drug resistance is declining in Italy. However, the persistence of DRMs to NRTIs and NNRTIs suggests that despite adherence and treatment optimisation, some patients still experience therapy failure, emphasising the need for GRTs both in naïve and ART-failed patients.