Phylogeography and genomic epidemiology of SARS-CoV-2 in Italy and Europe with newly characterized Italian genomes between February-June 2020.

The aims of this study were to characterize new SARS-CoV-2 genomes sampled all over Italy and to reconstruct the origin and the evolutionary dynamics in Italy and Europe between February and June 2020. The cluster analysis showed only small clusters including < 80 Italian isolates, while most of the Italian strains were intermixed in the whole tree. Pure Italian clusters were observed mainly after the lockdown and distancing measures were adopted. Lineage B and B.1 spread between late January and early February 2020, from China to Veneto and Lombardy, respectively. Lineage B.1.1 (20B) most probably evolved within Italy and spread from central to south Italian regions, and to European countries. The lineage B.1.1.1 (20D) developed most probably in other European countries entering Italy only in the second half of March and remained localized in Piedmont until June 2020. In conclusion, within the limitations of phylogeographical reconstruction, the estimated ancestral scenario suggests an important role of China and Italy in the widespread diffusion of the D614G variant in Europe in the early phase of the pandemic and more dispersed exchanges involving several European countries from the second half of March 2020.

Emerging issue of fluconazole-resistant candidemia in a tertiary care hospital of southern italy: time for antifungal stewardship program.

An increased number of patients is at risk of Candida spp. bloodstream infection (CBSI) in modern medicine. Moreover, the rising of antifungal resistance (AR) was recently reported. All consecutive CBSI occurred in our Hospital (consisting of 1,370 beds) between 2015 and 2018, were reviewed. For each case, Candida species, AR pattern, ward involved and demographic data of patients were recorded. Overall, 304 episodes of CBSI occurred, with a median (q1:first-,q3:third quartile) of 77 (71-82) CBSI/year. Over the years, a significant increase of CBSI due to C. albicans compared to non-albicans strains was recorded in medical wards (from 65% to 71%, p=0.030), while this ratio remained stable in others. An increase of resistant strains to multiple antifungals such as C. guillermondii was noticed in recent years (from 0% to 9.8%, p=0.008). Additionally, from 2015 to 2018 an increase in fluconazole-resistance was recorded in our Hospital (from 7.4% to 17.4%, p=0.025) and a slight increase in voriconazole-resistance (from 0% to 7% in 2018, p=0.161) was observed, while resistance to echinocandin and amphotericin B remained firmly below 2%. This study suggests a rapid spread of antifungal resistance in our Hospital; therefore, an appropriate antifungal stewardship programs is urgently warranted.

Prevalence of resistance-associated substitutions to NS3, NS5A and NS5B inhibitors at DAA-failure in hepatitis C virus in Italy from 2015 to 2019.

Despite the high efficacy of direct-acting antivirals (DAAs), the selection of resistance-associated substitutions (RASs) after virological failure of hepatitis C virus (HCV) DAAs can impair the cure of chronic HCV. The aim of the study was to characterize RASs after virological failure of DAAs in Italy over the years. Within the Italian network VIRONET-C, the change in prevalence of NS3/4A-NS5A-NS5B RASs was retrospectively evaluated in patients who failed a DAA regimen over the years 2015-2019. NS3, NS5A and NS5B Sanger sequencing was performed using homemade protocols and the geno2pheno system was used to define HCV-genotype/subtype and predict drug resistance. The changes in the prevalence of RASs over time were evaluated using the chi-square test for trend. Predictors of RASs at failure were analysed by logistic regression. Among 468 HCV-infected patients, HCV genotype 1 was the most prevalent (1b in 154, 33% and 1a in 109, 23%). DAA regimens were: ledipasvir (LDV)/sofosbuvir (SOF) in 131 patients (28%), daclatasvir (DCV)/SOF in 109 (23%), ombitasvir/paritaprevir/ritonavir+dasabuvir (3D) in 89 (19%), elbasvir (EBR)/grazoprevir (GRZ) in 52 (10.5%), velpatasvir (VEL)/SOF in 53 (11%), glecaprevir (GLE)/pibrentasvir (PIB) in 27 (6%) and ombitasvir/paritaprevir/ritonavir (2D) in 7 (1.5%); ribavirin was administered in 133 (28%). The NS5A fasta sequence was available for all patients, NS5B and NS3/4A both for 93%. The prevalence of NS5A and NS3/4A RASs significantly declined from 2015 to 2019; NS5B RAS remained stable. Independent predictors of any RASs included older age and genotype 1a (vs G2 and vs G4). Notably, at least partial susceptibility to all the agents included in the GLE/PIB and VEL/SOF/Voxilaprevir (VOX) combinations was predicted in >95% of cases. As RASs remain common at the failure of DAAs, their identification could play a crucial role in optimizing re-treatment strategies. In Italy RAS prevalence has been decreasing over the years and susceptibility to the latest developed drug combinations is maintained in most cases.

Incidence of Infections and Predictors of Mortality During Checkpoint Inhibitor Immunotherapy in Patients With Advanced Lung Cancer: A Retrospective Cohort Study.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have revolutionized nonsmall cell lung cancer (NSCLC) treatment and significantly increased overall survival of patients. However, the incidence of concurrent infections and their management is still debated. METHODS: From August 2015 to October 2019, all consecutive patients with NSCLC who received nivolumab or pembrolizumab as first- or second-line therapy were retrospectively evaluated. At the time of analysis all patients had died. Clinical characteristics of patients, type of infections, and predictors of mortality were analyzed. RESULTS: A total of 118 patients were identified: 74 in the nivolumab group and 44 in the pembrolizumab group. At least 1 infection was recorded in 22% of the nivolumab-group versus 27% of the pembrolizumab-group (P = .178). In both groups, the main infection was pneumonia, followed by skin and soft tissue infections, urinary tract infections, and gastroenteritis. Crude mortality for first infection was 10.7%, followed by 25% and 40% for the second and third recurrence, respectively (p for trend = .146). No opportunistic infections were recorded. It is notable that, by Cox-regression model, the independent predictor of mortality was a higher Eastern Cooperative Oncology Group performance status at baseline (P < .001), whereas the multidisciplinary diagnosis and treatment of concurrent infections was associated with a reduced probability of mortality (adjusted hazard ratio = 0.50; 95% confidence interval = 0.30-0.83; P < .001). CONCLUSIONS: In patients with NSCLC treated with ICIs, multidisciplinary management of concurrent infections may reduce the risk of mortality. Further studies to investigate risk factors for infections, as well as appropriate management strategies and preventive measures in this setting, are warranted.

Anti-spike S1 receptor-binding domain antibodies against SARS-CoV-2 persist several months after infection regardless of disease severity.

Data regarding the immunological memory and long-time kinetics of immunoglobulin (IgG) against viral nucleoprotein (NP) and spike protein S1 receptor-binding domain (S1RBD) of Severe Acute Respiratory Syndrome-associated Coronavirus 2 (SARS-CoV-2) are lacking. All consecutive COVID-19 patients admitted to our Clinic between March 1, 2020, and May 1, 2020, who were tested at hospital admission for anti-S1RBD and anti-NP IgG were enrolled. Serum samples were tested for anti-SARS-CoV-2 antibodies with the use of two commercially available enzyme-linked immunosorbent assays. Results are expressed as optical density measurements at 450 nm (OD450 ). Overall, 111 patients were included; the median (q1-q3) age was 57 (49-73) years, 59 (53%) males. According to disease severity, 31 (28%), 47 (42%), and 33 (30%) patients were considered affected by mild/moderate, severe, and critical SARS-CoV-2 infection, respectively. During hospitalization, patients with the critical disease showed a higher peak value of both anti-NP (median OD450 : 3.66 vs. 3.06 vs. 3.00 respectively, p = .043) and anti-S1RBD IgG (median OD450 : 2.33 vs. 1.6 vs. 0.91, respectively, p < .001). By testing 48 subjects 6 months or above from discharge, a significant decrease of anti-NP IgG was observed (r: -0.5838; p < .0001), whereas anti-S1RBD IgG showed only a modest reduction (r: -0.1507; p = .0647). Accordingly, 10 (21%) and 2 (4%) patients had a negative serological status for anti-NP and anti-S1RBD IgG, respectively; no association with clinical severity was found. IgGs against SARS-CoV-2 persisted several months after discharge, regardless of disease severity, suggesting that vaccination could be a valid strategy to fight the pandemic.

Recurrent neurosurgical site infection by extensively drug-resistant P. aeruginosa treated with cefiderocol: a case report and literature review.

INTRODUCTION: Cefiderocol is a new siderophore cephalosporin designed to be active against extensively resistant Gram-negative bacteria; however, clinical studies are limited to complicated urinary tract infections, pneumonia, and intra-abdominal infections. To date, no data are available on neurosurgical site infections. CASE PRESENTATION: We present a case of a patient successfully cured with Cefiderocol for a neurosurgical site infection due to extensively resistant P. aeruginosa, who had failed a previous treatment based on combined antimicrobial therapy and right parietal bone excision. CONCLUSIONS: Cefiderocol is a promising antibiotic for complicated infections due to multidrug resistant gram-negative bacteria.

Lost to follow-up: a challenge over 10 years.

The loss of patients to follow up is a major issue related to HIV management. Our research was aimed to evaluate, in a single Italian centre, the rate of patients lost to follow-up (LFU) over 10 years, to describe their socio-demographic and clinical features, and to identify predictors of disengagement from care. Between 2008 and 2017, 563 subjects were LFU. Over the years, the proportion of LFU on the number of patients followed per year, decreased from 6.5% in 2008 to 4.8% in 2017 (p for trend = 0.255). Four different subgroups were identified among LFU:116 patients resulted untraceable; 192 had died; 144 were re-engaged elsewhere; 111 were subsequently re-engaged in our centre. Old age (OR 1.08, 95%, CI = 1.06-1.11; p < 0.001), AIDS (OR = 1.66, 95% CI = 1.04-2.64; p = 0.031), drug addiction (OR = 1.91, 95% CI = 1.07-3.41; p = 0.027) were predictors of death at multivariable analysis. Main predictors of being untraceable were non-Italian nationality (OR = 4.23, 95% CI = 2.19-8.16; p < 0.001) and a short history of cART (OR = 0.93, 95% CI = 0.88-0.99; p = 0.026). Subjects living far from our Centre were often re-engaged elsewhere (OR = 2.36, 95% CI = 1.34-4.15; p = 0.002). According to our analysis, the problem LFU is still relevant: strategies to empower retention in care are thus necessary.

Long-term maintenance of virologic suppression in native and migrant HIV-1 naïve patients: an Italian cohort study.

Little is known about long-term maintenance of virologic suppression in HIV migrants in Italy. The study aims to compare virologic failure rates and associated factors among antiretroviral therapy (ART)-naïve migrants and natives enrolled in the ARCA database since 2007 who achieved virologic suppression within 18 months from the beginning of the ART. Kaplan-Meier method assessed the probability of virologic suppression and failure. Cox regression model was used for multivariate analysis. Of 2515 patients, 2020 (80.3%) were Italian, 286 (10.6%) migrants from low-income countries, of whom 201 (75.0%) from Africa, and 227 (9.0%) from high-income-countries. The median follow-up was 4.5 years (IQR 2.5-7). No difference was observed in the time of achievement of virological suppression in the three groups (log-rank: p = 0.5687). Higher probability of virologic failure was observed in Africans compared to Italians, to patients from high-income-countries and from low-income-countries other than Africans (Log-rank = p < 0.001). In the adjusted analysis, a higher virologic failure risk was found in Africans only compared to Italians. [HR 4.01; 95% CI 2.44-6.56, p < 0.001]. In Italy, African migrants are less likely to maintain virologic suppression compared to natives and other migrants. Targeted interventions could be needed for foreigners, especially for Africans.

Influence of HIV-1 V2 sequence variability on bacterial translocation in antiretroviral naïve HIV-1 infected patients.

HIV-1 V2 domain binds α4ß7, which assists lymphocyte homing to gut-associated lymphoid tissue. This triggers bacterial translocation, thus contributing to immune activation. We investigated whether variability of V2 179-181 binding site could influence plasma levels of lipopolysaccharide (LPS) and soluble cluster of differentiation 14 (sCD14), markers of microbial translocation/immune activation. HIV gp120 sequences from antiretroviral naïve patients were analyzed for V2 tripeptide composition, length, net charge, and potential N-linked-glycosylation sites. LPS and sCD14 plasma levels were quantified. Clinical/immuno-virologic data were retrieved. Overall, 174 subjects were enrolled, 8% with acute infection, 71% harboring a subtype B. LDV179-181 was detected in 41% and LDI in 27%. No difference was observed between levels of LPS or sCD14 according to different mimotopes or according to other sequence characteristics. By multivariable analysis, only acute infection was significantly associated with higher sCD14 levels. In conclusion, no association was observed between V2 tripeptide composition and extent of bacterial translocation/immune activation.

Infection caused by Sporothrix schenckii: an autochthonous case in Bari, Southern Italy.

An autochthonous case of lymphocutaneous sporotrichosis caused by Sporothrix schenckii is reported. The patient developed skin lesions localized along the lymphatics that appeared after he suffered an injury while collecting wicker canes in marshy water. The fungus was identified as Sporothrix schenckii by MALDI-TOF and sequencing. Phylogenetic analysis was also performed. Low MIC values were detected for all tested echinocandins and azoles except for fluconazole. The patient was treated with itraconazole without significant improvement. A regression of lesions was observed after 3 months of therapy with voriconazole. Few cases of sporotrichosis have been reported in Europe. However, several cases of sporotrichosis have been described in Italy. The incidence of sporotrichosis in Italy may be underestimated and microbiologists, and clinicians must be aware of this fungal infection.

Targeted therapies for autoimmune/idiopathic nonmalignant diseases: risk and management of opportunistic infections.

INTRODUCTION: The management of patients affected by autoimmune/idiopathic diseases has been revolutionized by the development of targeted therapies (TT). However, the use of TT is complicated by several adverse events, like opportunistic infections (OIs). The potential of TT to predispose to OIs mainly depends on the site of action; nevertheless, such associations are far from being deterministic, because many factors could increase the infection risk. AREAS COVERED: The impact on the infective risk of different TT used for autoimmune/idiopathic diseases is far from being completely understood. Indeed, many post-marketing reports documented severe or unexpected infections in patients treated with TT that did not emerge during registrative trials. In this review, the authors attempt to provide an easy and practical update about the 'infectious' safety of TT and examine the management strategies of OIs and other infections more frequently observed in the course of treatment with TT. EXPERT OPINION: The authors suggest to precisely schedule the clinical management of these subjects, both to prevent and eventually treat promptly the TT-related infectious complications. A coordinated approach should be implemented from different medical specialties to improve the overall understanding of safety of TT and, in general, the management of opportunistic infections in immune-compromised hosts.

Gp120 substitutions at positions associated with resistance to fostemsavir in treatment-naive HIV-1-positive individuals.

OBJECTIVES: Fostemsavir, a novel attachment inhibitor targeting the HIV-1 gp120, has demonstrated wide in vitro activity. However, the high rate of HIV gp120 substitutions could jeopardize its efficacy. We investigated envelope (env) substitutions at positions associated with resistance to fostemsavir in patients with a new HIV-1 diagnosis according to HIV subtype and tropism. METHODS: Gp120 sequences from 409 subjects were retrospectively analysed and the presence of the L116P, A204D, S375H/M/T, M426L, M434I and M475I mutations was evaluated. Other amino acid changes at the same positions were also recorded. The variability at each amino acid position was evaluated using Shannon entropy. RESULTS: The frequency of mutations was: S375T (13.2%); M426L (6.8%); M434I (2.9%); M475I (2.7%); S375H (1.0%)/M (0.8%) and L116P (0.31%). Statistically significant differences were found at positions 375 (R5/non-R5 strains and B/non-B subtypes) and 426 (B/non-B subtypes); post hoc analysis revealed that significance for position 375 was steered by S375T while for position 426 significance was governed by unusual substitutions, in particular M426R (B/non-B, P < 0.00001). The variability of env constant domains appeared to be more relevant in the non-B virus population. CONCLUSIONS: In conclusion, gp120 substitutions were detected in different subtypes and in both R5 and non-R5 variants. Despite the great variability of gp120, the frequency of mutations was low overall and the predominant substitution was S375T, the role of which in reducing fostemsavir efficacy is less substantial.

Pretreatment HIV drug resistance and treatment failure in non-Italian HIV-1-infected patients enrolled in ARCA.

BACKGROUND: An increase in pretreatment drug resistance (PDR) to first-line antiretroviral therapy (ART) in low-income countries has been recently described. Herein we analyse the prevalence of PDR and risk of virological failure (VF) over time among migrants to Italy enrolled in ARCA. METHODS: HIV-1 sequences from ART-naive patients of non-Italian nationality were retrieved from ARCA database from 1998 to 2017. PDR was defined by at least one mutation from the reference 2009 WHO surveillance list. RESULTS: Protease/reverse transcriptase sequences from 1,155 patients, mainly migrants from sub-Saharan Africa (SSA; 42%), followed by Latin America (LA; 25%) and Western countries (WE; 21%), were included. PDR was detected in 8.6% of sequences (13.1% versus 5.8% for B and non-B strains, respectively; P<0.001). 2.1% of patients carried a PDR for protease inhibitors (PIs; 2.1% versus 2.3%; P=0.893), 3.9% for nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs; 6.8% versus 2.1%; P<0.001) and 4.3% for non-nucleoside/nucleotide reverse transcriptase inhibitors (NNRTIs; 6.3% versus 3.1%; P=0.013). Overall, prevalence of PDR over the years remained stable, while it decreased for PIs in LA (P=0.021) and for NRTIs (P=0.020) among migrants from WE. Having more than one class of PDR (P=0.015 versus absence of PDR), higher viral load at diagnosis (P=0.008) and being migrants from SSA (P=0.001 versus WE) were predictive of VF, while a recent calendar year of diagnosis (P<0.001) was protective for VF. CONCLUSIONS: PDR appeared to be stable over the years in migrants to Italy enrolled in ARCA; however, it still remains an important cause of VF together with viral load at diagnosis.

Efficacy and tolerability of DAAs in HCV-monoinfected and HCV/HIV-coinfected patients with psychiatric disorders.

BACKGROUND: Few data are available regarding the use of direct antiviral agents (DAAs) for chronic hepatitis C in psychiatric patients. The aim of the study is to assess safety and outcome of DAAs in patients with psychiatric comorbidities. METHODS: This retrospective, observational, single-centre study enrolled patients treated with psychiatric drugs who initiated DAAs between 2015 and 2018. Patients were classified into two groups: A (on anxiolitycs/antidepressant) and B (on antipsychotics). Week-12 sustained virological response (SVR-12) and adverse events (AEs) were evaluated. RESULTS: One hundred forty-four patients were included (A:101; B:43). Patients were 49.3% males, mean age 60 years (SD ± 13.5); 31.9% cirrhotic; 125 (86.8%) HCV-monoinfected and 19 (13.2%) HCV /HIV-coinfected. Twenty patients (13.8%) required a change of psychiatric therapy before initiation of DAA. Overall, SVR-12 was achieved in 88.2% of subjects in intention-to-treat(ITT)-analysis. Lower SVR rates were observed in group B vs A (79% vs 92%, p = 0.045) and in those changing psychiatric drugs vs others (8% vs 30%, p = 0.015). According to per-protocol (PP)-analysis, SVR-12 was achieved in 93/95 (97.9%) in group A versus 34/36 (94.4%) in group B (p = 0.30). At least one AE occurred in 60 patients (41.6%), including 10 severe AEs, leading to 3 discontinuations. AEs were more frequently reported in group A (p = 0.015). CONCLUSIONS: The study confirms effectiveness and safety of DAA-based treatment also in this special population, even if a careful evaluation of history and drug-drug interactions is warranted.

High HIV-1 diversity in immigrants resident in Italy (2008-2017).

The proportion of new diagnoses of HIV infection in immigrants residing in Italy raised from 11% in 1992 to 29.7% in 2018. To investigate the HIV clades circulating in this community a retrospective study was performed in 557 HIV-infected immigrants living in 12 Italian cities. Immigrants originated from East-Europe and Central-Asia (11.7%), North Africa and Middle East (7.3%), South and South-East Asia (7.2%), Latin America and the Caribbean (14.4%), and sub-Saharan Africa (59.4%). More than 87% of immigrants were on antiretroviral therapy (ART), although 26.6% of them were viremic. A 22.0% of immigrants had hepatitis (HBV and/or HCV) and/or tuberculosis. HIV phylogenetic analysis on sequences from 192 immigrants showed the presence of clades B (23.4%), G (16.1%), C (10.4%), A1 (9.4%), F1 (5.2%), D (1.6%) and Circulating Recombinant Forms (CRFs) (33.9%). CRF02_AG represented 72.3% of the total CRFs. Clusters between immigrants and Italian natives were also present. Drug resistance mutations to NRTI, NNRTI, and PI drug classes occurred in 29.1% of ART-treated and in 12.9% of ART-naïve individuals. These data highlight the need for tailored public health interventions in immigrants to avoid spreading in Italy of HIV genetic forms and ART-resistant variants, as well as HIV co-morbidities.

Capacity assessment for provision of quality sexual reproductive health and HIV-integrated services in Karamoja, Uganda.

INTRODUCTION: Sexual and reproductive health (SRH) and Human Immunodeficiency Virus (HIV) are crucial global health issues. Uganda continues to sustain a huge burden of HIV and AIDS. METHODS: A cross-sectional health facility-based assessment was performed in November and December 2016 in Karamoja Region, northern Uganda. All the 126 health facilities (HFs) in Karamoja, including 5 hospitals and 121 Health Centers (HCs), covering 51 sub-counties of the 7 districts were assessed. We assessed the capacity of a) leadership and governance, b) human resource, c) service delivery, d) SRH and HIV service integration and e) users satisfaction and perceptions. RESULTS: 64% of the established health staffing positions were filled leaving an absolute gap of 704 units in terms of human resources. As for service delivery capacity, on 5 domains assessed, the best performing was basic hygiene and safety measures in which 33% HCs scored "excellent", followed by the presence of basic equipment. The level of integration of SRH/HIV services was 55.56%. CONCLUSION: HFs in Karamoja have capacity gaps in a number of health system building blocks. Many of these gaps can be addressed through improved planning. To invest in improvements for these services would have a great gain for Uganda.

HIV rapid test in a community setting as a strategy to improve access to HIV testing: data from a multicentre experience in Italy.

4,000 new HIV diagnoses and approximately 800 AIDS cases are still reported annually in Italy. Improving public awareness and bringing out HIV-undiagnosed individuals are keystones to progress towards the control of the HIV epidemic. For this purpose, the Open HIV TEST project was organized and delivered by the Italian NGO Anlaids, together with local infectious diseases specialists, in order to provide free access to HIV testing outside the healthcare setting. Between October 2017 and February 2019 six Open HIV TEST initiatives were delivered in six Italian cities (3 northern cities, 1 central and 2 southern cities). In all, 581 people were tested: the overall prevalence of HIV test reactivity was 0.7%. Participants were also asked about previous screenings and about their satisfaction with the initiative: previous HIV screening due to pregnancy or surgical procedures was reported mainly by participants in northern centres (p<0.001); finally, the initiative was considered useful and noteworthy by 99% of participants. Prevalence of HIV test reactivity in our experience was in line with national data. Our experience suggests that active testing and counselling strategies in community settings should be recommended and institutionalized by local health authorities in line with the 90-90-90 global strategy.

No impact of previous NRTIs resistance in HIV positive patients switched to DTG+2NRTIs under virological control: Time of viral suppression makes the difference.

The accumulation of drug-resistance mutations on combined antiretroviral regimens (ART) backbone could affect the virological efficacy of the regimen. Our aim was to assess the impact of previous drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs) on the probability of virological failure (VF) in patients, under virological control, who switched to dolutegravir (DTG)+2NRTIs regimens. All HIV-1 positive drug-experienced patients who started a regimen composed by DTG+2NRTIs [abacavir/lamivudine or tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF)/emtricitabine (FTC)] in the ARCA collaborative group with HIV-RNA <50 cp/mL were included in the analysis. Patients with a previous VF to integrase inhibitors were excluded. The impact of single and combined NRTIs mutations on the probability of VF (defined as 2 consecutive HIV-RNA >50 copies/mL or one HIV-RNA >1000 copies/mL) was assessed by Kaplan Meier curves. A multivariable Cox regression analysis was constructed to assess factors potentially related to VF. Five hundred and eighty-eight patients were included in the analysis with a median time of viral suppression before the switch of 37 months (IQR 12-78), of whom 148 (25.2%) had at least one previous NRTIs resistance mutation. In the multivariable model no association was observed between NRTIs mutations and VF. Conversely, the duration of viral suppression before switch resulted associated with a lower risk of VF (for 1 month increase, adjusted Hazard Ratio 0.98, 95%CI 0.96-0.99; p=0.024). Previous NRTIs mutations appeared to have no impact on the risk of VF in patients switched to DTG+2NRTIs, whereas a longer interval on a controlled viremia decreased significantly the risk of VF.