HIV-1 drug resistance and genetic diversity in people with HIV-1 in Cape Verde, 2019-2021.

OBJECTIVES: To characterize the genetic diversity and drug resistance profiles of people with HIV-1 failing ART in Cape Verde (CV). DESIGN: Cross- sectional study conducted between January 2019 and December 2021 in 24 health centres on the islands of Santiago and São Vicente. METHODS: The HIV-1 pol gene was sequenced in individuals with a detectable viral load (VL). HIV-1 genetic diversity was determined by phylogenetic analysis. Drug resistance mutation patterns and resistance phenotypes were estimated using the Stanford algorithm. RESULT: VL was detected in 73 of 252 (29%) enrolled participants and sequencing data were produced for 58 (79%) participants. CRF02_AG strains predominated (46.5%), followed by subtype G (22.4%). Most patients (80%) had mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) (67%), nucleoside reverse transcriptase inhibitors (55%), integrase inhibitors (10%) and/or protease inhibitors (7%) used in CV, a significant increase compared to a study conducted in 2010-2011. The most common mutations were M184 V/I (43%), K103N/S (36%) and G190A/S (19%). NNRTI resistance was associated with younger age and exposure to two or more drug regimens. CONCLUSIONS: The HIV-1 epidemic in Cape Verde is mainly driven by CRF02_AG and subtype G. Resistance to NNRTIs and/or NRTIs is highly prevalent and resistance to LPV/r and DTG is emerging. Our results support the use of DTG-based first-line ART and PI-based regimens for patients with virological failure, but emerging resistance to LPV/r and DTG is a concern. Continued monitoring of drug resistance is essential to ensure adequate health care for PLWH in Cape Verde.

Long-Term and Low-Level Envelope C2V3 Stimulation by Highly Diverse Virus Isolates Leads to Frequent Development of Broad and Elite Antibody Neutralization in HIV-1-Infected Individuals.

A minority of HIV-1-infected patients produce broadly neutralizing antibodies (bNAbs). Identification of viral and host correlates of bNAb production may help develop vaccines. We aimed to characterize the neutralizing response and viral and host-associated factors in Angola, which has one of the oldest, most dynamic, and most diverse HIV-1 epidemics in the world. Three hundred twenty-two HIV-1-infected adults from Angola were included in this retrospective study. Phylogenetic analysis of C2V3C3 env gene sequences was used for virus subtyping. Env-binding antibody reactivity was tested against polypeptides comprising the C2, V3, and C3 regions. Neutralizing-antibody responses were determined against a reference panel of tier 2 Env pseudoviruses in TZM-bl cells; neutralizing epitope specificities were predicted using ClustVis. All subtypes were found, along with untypeable strains and recombinant forms. Notably, 56% of the patients developed cross neutralizing, broadly neutralizing, or elite neutralizing responses. Broad and elite neutralization was associated with longer infection time, subtype C, lower CD4+ T cell counts, higher age, and higher titer of C2V3C3-specific antibodies relative to failure to develop bNAbs. Neutralizing antibodies targeted the V3-glycan supersite in most patients. V3 and C3 regions were significantly less variable in elite neutralizers than in weak neutralizers and nonneutralizers, suggesting an active role of V3C3-directed bNAbs in controlling HIV-1 replication and diversification. In conclusion, prolonged and low-level envelope V3C3 stimulation by highly diverse and ancestral HIV-1 isolates promotes the frequent elicitation of bNAbs. These results provide important clues for the development of an effective HIV-1 vaccine. IMPORTANCE Studies on neutralization by antibodies and their determinants in HIV-1-infected individuals have mostly been conducted in relatively recent epidemics caused by subtype B and C viruses. Results have suggested that elicitation of broadly neutralizing antibodies (bNAbs) is uncommon. The mechanisms underlying the elicitation of bNAbs are still largely unknown. We performed the first characterization of the plasma neutralizing response in a cohort of HIV-1-infected patients from Angola. Angola is characterized by an old and dynamic epidemic caused by highly diverse HIV-1 variants. Remarkably, more than half of the patients produced bNAbs, mostly targeting the V3-glycan supersite in HIV-1. This was associated with higher age, longer infection time, lower CD4+ T cell counts, subtype C infection, or higher titer of C2V3C3-specific antibodies relative to patients that did not develop bNAbs. These results may help develop the next generation of vaccine candidates for HIV-1.

Dynamics of HIV Reservoir and HIV-1 Viral Splicing in HCV-Exposed Individuals after Elimination with DAAs or Spontaneous Clearance.

Background: Although human immunodeficiency virus type 1 (HIV-1) reservoir size is very stable under antiretroviral therapy (ART), individuals exposed to the Hepatitis C virus (HCV) (chronically coinfected and spontaneous clarifiers) show an increase in HIV reservoir size and in spliced viral RNA, which could indicate that the viral protein regulator Tat is being more actively synthesized and, thus, could lead to a higher yield of new HIV. However, it is still unknown whether the effect of HCV elimination with direct-acting antivirals (DAAs) could modify the HIV reservoir and splicing. Methods: This longitudinal study (48 weeks' follow-up after sustained virological response) involves 22 HIV+-monoinfected individuals, 17 HIV+/HCV- spontaneous clarifiers, and 24 HIV+/HCV+ chronically infected subjects who eliminated HCV with DAAs (all of them aviremic, viral load < 50). Viral-spliced RNA transcripts and proviral DNA copies were quantified by qPCR. Paired samples were analyzed using a mixed generalized linear model. Results: A decrease in HIV proviral DNA was observed in HIV+/HCV- subjects, but no significant differences were found for the other study groups. An increased production of multiple spliced transcripts was found in HIV+ and HIV+/HCV+ individuals. Conclusions: We conclude that elimination of HCV by DAAs was unable to revert the consequences derived from chronic HCV infection for the reservoir size and viral splicing, which could indicate an increased risk of rapid HIV-reservoir reactivation. Moreover, spontaneous clarifiers showed a significant decrease in the HIV reservoir, likely due to an enhanced immune response in these individuals.

Different HCV Exposure Drives Specific miRNA Profile in PBMCs of HIV Patients.

Micro RNAs (miRNAs) are essential players in HIV and HCV infections, as both viruses modulate cellular miRNAs and interact with the miRNA-mediated host response. We aim to analyze the miRNA profile of HIV patients with different exposure to HCV to explore specific signatures in the miRNA profile of PBMCs for each type of infection. We massively sequenced small RNAs of PBMCs from 117 HIV+ infected patients: 45 HIV+ patients chronically infected with HCV (HIV/HCV+), 36 HIV+ that spontaneously clarified HCV after acute infection (HIV/HCV-) and 36 HIV+ patients without previous HCV infection (HIV). Thirty-two healthy patients were used as healthy controls (HC). Differential expression analysis showed significantly differentially expressed (SDE) miRNAs in HIV/HCV+ (n = 153), HIV/HCV- (n = 169) and HIV (n = 153) patients. We found putative dysregulated pathways, such as infectious-related and PI3K signaling pathways, common in all contrasts. Specifically, putatively targeted genes involved in antifolate resistance (HIV/HV+), cancer-related pathways (HIV/HCV-) and HIF-signaling (HIV) were identified, among others. Our findings revealed that HCV strongly influences the expression profile of PBMCs from HIV patients through the disruption of its miRNome. Thus, different HCV exposure can be identified by specific miRNA signatures in PBMCs.

Epidemic history and baseline resistance to NS5A-specific direct acting drugs of hepatitis C virus in Spain.

Hepatitis C virus (HCV) infection remains a global health problem. Previously, the prevalence of NS5A resistance-associated substitutions (RASs) to elbasvir, a new direct-acting antiviral (DAA) against the NS5A viral protein was assessed by our group before its introduction into clinical use in Spain. However, the origin, epidemic history, transmission dynamics, diversity and baseline RASs to NS5A direct-acting agents of HCV-GT1a in Spain remain unknown. A nationwide cross-sectional survey of individuals chronically-infected with HCV-G1a and DAAs-naïve was performed. HCV population sequencing, phylogenetic analysis and Bayesian methods were used. GT1a clade II was more prevalent than clade I (82.3% vs. 17.7%; P < 0.001) and older (estimated origin in 1912 vs. 1952). Clade II epidemic is currently declining whereas clade I epidemic has reached equilibrium. A total of 58 single RASs were identified, which account for the moderate level (10%) of baseline resistance observed. When considering the regional data, marked differences were observed, with thirteen regions showing an intermediate level (5-15%) and one a high level (20%) of resistance. Current HCV-GT1a epidemic in Spain is driven by clade I which seem to have different dissemination routes relative to clade II. A moderate level of baseline RASs to NS5A-DAAs with marked differences among regions was observed. Close surveillance of response to treatment with DAAs will be important.

HCV-coinfection is related to an increased HIV-1 reservoir size in cART-treated HIV patients: a cross-sectional study.

In HIV-1/HCV-coinfected patients, chronic HCV infection leads to an increased T-lymphocyte immune activation compared to HIV-monoinfected patients, thereby likely contributing to increase HIV-1 reservoir that is the major barrier for its eradication. Our objective was to evaluate the influence of HCV coinfection in HIV-1 viral reservoir size in resting (r) CD4+ T-cells (CD25-CD69-HLADR-). Multicenter cross-sectional study of 97 cART-treated HIV-1 patients, including 36 patients with HIV and HCV-chronic co-infection without anti-HCV treatment, 32 HIV patients with HCV spontaneous clearance and 29 HIV-monoinfected patients. rCD4+ T-cells were isolated and total DNA was extracted. HIV viral reservoir was measured by Alu-LTR qPCR. Differences between groups were calculated with a generalized linear model. Overall, 63.9% were men, median age of 41 years and Caucasian. Median CD4+ and CD8+ T-lymphocytes were 725 and 858 cells/mm3, respectively. CD4+ T nadir cells was 305 cells/mm3. Proviral HIV-1 DNA size was significantly increased in chronic HIV/HCV-coinfected compared to HIV-monoinfected patients (206.21 ± 47.38 vs. 87.34 ± 22.46, respectively; P = 0.009), as well as in spontaneously clarified HCV co-infected patients when compared to HIV-monoinfected individuals (136.20 ± 33.20; P = 0.009). HIV-1/HCV co-infected patients showed a larger HIV-1 reservoir size in comparison to HIV-monoinfected individuals. This increase could lead to a greater complexity in the elimination of HIV-1 reservoir in HIV-1/HCV-coinfected individuals, which should be considered in the current strategies for the elimination of HIV-1 reservoir.

Epidemic history of hepatitis C virus genotypes and subtypes in Portugal.

Any successful strategy to prevent and control HCV infection requires an understanding of the epidemic behaviour among the different genotypes. Here, we performed the first characterization of the epidemic history and transmission dynamics of HCV subtypes in Portugal. Direct sequencing of NS5B was performed on 230 direct-acting antiviral drugs (DAA)-treatment naïve patients in Lisbon. Phylogenetic analysis was used for subtyping and transmission cluster identification. Bayesian methods were used to reconstruct the epidemic history of HCV subtypes. Sequences were analysed for resistance-associated substitutions (RAS). The majority of strains were HCV-GT1 (62.6%), GT3 (18.3%, all subtype 3a) and GT4 (16.1%). Among GT1, the most frequent were subtypes 1a (75.5%) and 1b (24.5%). Polyphyletic patterns were found in all but 12 lineages suggesting multiple introductions of the different subtypes in this population. Five distinct epidemics were identified. The first significant HCV epidemic in Portugal occurred between 1930s and 1960s, was caused almost exclusively by GT1b and was likely associated with blood transfusions. Rapid expansion of GT3a occurred in the 1960s and GT1a in the 1980s, associated with intravenous drug use. The most recent epidemics were caused by GT4a and GT4d and seem to be associated with the resurgence of opioid use. The C316N substitution was found in 31.4% of GT1b-patients. Close surveillance of patients bearing this mutation and undergoing dasabuvir-based regimens will be important to determine its impact on treatment outcome.

Frecuencia de sustituciones relevantes asociadas a resistencia en la región NS5A a elbasvir en el virus de la hepatitis C en pacientes con genotipo 1a en España / Prevalence of relevant NS5A resistance-associated substitutions to elbasvir in genotype 1a hepatitis C virus patients in Spain

Las sustituciones asociadas a resistencia (RAS) a elbasvir, el nuevo inhibidor de la NS5A del virus de la hepatitis C (VHC), pueden presentar relevancia al limitar su eficacia y conducir al fracaso virológico en pacientes infectados por VHC genotipo 1a (GT1a) a diferencia de lo observado en GT1b y GT4. No existen datos fuera de ensayos clínicos que evalúen la prevalencia y el impacto de grazoprevir/elbasvir en pacientes infectados con GT1a en España. Se llevó a cabo un estudio transversal multicéntrico en 632 pacientes iniciales, en 13 de los cuales no se consiguió amplificar la muestra o no fue válida para alcanzar una secuencia consenso mediante secuenciación de Sanger. Finalmente, se analizaron 617 individuos infectados con VHC-GT1a atendidos en 84 hospitales distribuidos por las 17 comunidades autónomas más las 2 ciudades autónomas que conforman el territorio español. La población de VHC secuenciada se ha usado para identificar RAS a elbasvir, mientras que el patrón mutacional y la sensibilidad farmacológica se confirmaron mediante geno2pheno[HCV]. Los virus portadores de RAS a elbasvir se observaron en el 6,2% de los pacientes infectados con el VHC-G1a. Las RAS más comunes fueron Y93C/H/N y Q30E/H/R (2,4 y 2,3%, respectivamente). Solo el 3,4% de las RAS a elbasvir identificadas confirieron susceptibilidad reducida al fármaco mediante geno2pheno[HCV] que identificó exclusivamente como principales RAS a elbasvir las posiciones Q30H/R (n = 7) y Y93C/H/N (n = 8) como mutaciones simples y Q30H+Y93H (n = 4) y Q30R+Y93H (n = 2) como mutaciones dobles. En nuestra cohorte española con VHCG1a se observó una menor prevalencia de RAS a elbasvir que la reportada previamente en ensayos clínicos realizados en pacientes norteamericanos. Esta información puede ser esencial para el manejo de los pacientes infectados con G1a y guiar la implementación de grazoprevir/elbasvir en España

Resistance-associated substitutions (RASs) to the new HCV NS5A inhibitor elbasvir may limit its efficacy and lead to virological failure in HCV-GT1a-infected patients. There are no data outside clinical trials evaluating their prevalence and impact in grazoprevir/elbasvir in GT1a-infected patients in Spain. A multicentre cross-sectional study of 632 initial patients was conducted. In 13 of these patients, the sample could not be amplified or a consensus sequence by Sanger sequencing could not be performed. Ultimately, 617 HCV-G1a-infected individuals treated at 84 Spanish hospitals from the 17 autonomous communities plus the 2 autonomous cities of Spain were analysed. HCV population sequencing was used to identify RAS to elbasvir and the mutational pattern and drug sensitivity were confirmed by geno2pheno[HCV]. Viruses bearing RASs to elbasvir were present in 6.2% of HCV-G1a infected patients. The most common RASs were the Y93C/H/N and Q30E/H/R (2.4% and 2.3%, respectively). Only 3.4% of the identified RASs to elbasvir conferred reduced susceptibility to elbasvir by geno2pheno[HCV], which exclusively identified the positions Q30H/R (n = 7) and Y93C/H/N (n = 8) as single mutations and Q30H+Y93H (n = 4) and Q30R+Y93H (n = 2) as double mutations as the major RASs to elbasvir. A lower prevalence of RASs to elbasvir was observed in our HCV-G1a Spanish cohort than reported previously in clinical trials evaluating patients from the USA. This information may be essential to guide the implementation of grazoprevir/elbasvir in Spain and to manage G1a-infected patients

Prevalence of relevant NS5A resistance-associated substitutions to elbasvir in genotype 1a hepatitis C virus patients in Spain. / Frecuencia de sustituciones relevantes asociadas a resistencia en la región NS5A a elbasvir en el virus de la hepatitis C en pacientes con genotipo 1a en España.

Resistance-associated substitutions (RASs) to the new HCV NS5A inhibitor elbasvir may limit its efficacy and lead to virological failure in HCV-GT1a-infected patients. There are no data outside clinical trials evaluating their prevalence and impact in grazoprevir/elbasvir in GT1a-infected patients in Spain. A multicentre cross-sectional study of 632 initial patients was conducted. In 13 of these patients, the sample could not be amplified or a consensus sequence by Sanger sequencing could not be performed. Ultimately, 617 HCV-G1a-infected individuals treated at 84 Spanish hospitals from the 17 autonomous communities plus the 2 autonomous cities of Spain were analysed. HCV population sequencing was used to identify RAS to elbasvir and the mutational pattern and drug sensitivity were confirmed by geno2pheno[HCV]. Viruses bearing RASs to elbasvir were present in 6.2% of HCV-G1a infected patients. The most common RASs were the Y93C/H/N and Q30E/H/R (2.4% and 2.3%, respectively). Only 3.4% of the identified RASs to elbasvir conferred reduced susceptibility to elbasvir by geno2pheno[HCV], which exclusively identified the positions Q30H/R (n=7) and Y93C/H/N (n=8) as single mutations and Q30H+Y93H (n=4) and Q30R+Y93H (n=2) as double mutations as the major RASs to elbasvir. A lower prevalence of RASs to elbasvir was observed in our HCV-G1a Spanish cohort than reported previously in clinical trials evaluating patients from the USA. This information may be essential to guide the implementation of grazoprevir/elbasvir in Spain and to manage G1a-infected patients.

Early infant diagnosis of HIV-1 infection in Luanda, Angola, using a new DNA PCR assay and dried blood spots.

BACKGROUND: Early diagnosis and treatment reduces HIV-1-related mortality, morbidity and size of viral reservoirs in infants infected perinatally. Commercial molecular tests enable the early diagnosis of infection in infants but the high cost and low sensitivity with dried blood spots (DBS) limit their use in sub-Saharan Africa. OBJECTIVES: To develop and validate a sensitive and cheap qualitative proviral DNA PCR-based assay for early infant diagnosis (EID) in HIV-1-exposed infants using DBS samples. STUDY DESIGN: Chelex-based method was used to extract DNA from DBS samples followed by a nested PCR assay using primers for the HIV-1 integrase gene. Limit of detection (LoD) was determined by Probit regression using limiting dilutions of newly produced recombinant plasmids with the integrase gene of all HIV-1 subtypes and ACH-2 cells. Clinical sensitivity and specificity were evaluated on 100 HIV-1 infected adults; 5 infected infants; 50 healthy volunteers; 139 HIV-1-exposed infants of the Angolan Pediatric HIV Cohort (APEHC) with serology at 18 months of life. RESULTS: All subtypes and CRF02_AG were amplified with a LoD of 14 copies. HIV-1 infection in infants was detected at month 1 of life. Sensitivity rate in adults varied with viral load, while diagnostic specificity was 100%. The percentage of HIV-1 MTCT cases between January 2012 and October 2014 was 2.2%. The cost per test was 8-10 USD which is 2- to 4-fold lower in comparison to commercial assays. CONCLUSIONS: The new PCR assay enables early and accurate EID. The simplicity and low-cost of the assay make it suitable for generalized implementation in Angola and other resource-constrained countries.

Prioritizing the most needed formulations to accelerate paediatric antiretroviral therapy scale-up.

PURPOSE OF REVIEW: Initiatives are in place to reach super-fast targets by 2018 for paediatric patients living with HIV. However, these efforts are unlikely to be successful until better paediatric antiretrovirals and treatment strategies are available. This commentary reviews the specific features, challenges, and recent developments in paediatric HIV treatment to determine optimal regimen sequencing and use of available drug options. It also outlines a medium and long-term vision for treatment optimization as endorsed by the paediatric antiretroviral drug optimization group. RECENT FINDINGS: Optimizing antiretroviral therapy (ART) is critical in the context of limited treatment options for children. A first-line dolutegravir-based regimen is the long-term goal for paediatric first-line ART across all age groups. Protease inhibitor-based regimens are expected to continue to play a critical role for second and third-line treatment. New efforts are urgently needed to optimize treatment for children, ensuring access to existing drugs and speeding up development of newer and better formulations moving forward. SUMMARY: Over the last few years there have been a number of key developments in paediatric ART which offer the opportunity to reconsider the way ART is optimized for children. Additional evidence is needed to ensure optimal options are available from infancy through adulthood.

Low frequency of NS5A relevant resistance-associated substitutions to Elbasvir among hepatitis C virus genotype 1a in Spain: a cross-sectional study.

Relevant resistance-associated substitutions (RASs) to elbasvir, the new HCV NS5A inhibitor, may limit its efficacy and lead to virological failure in HCV-GT1a-infected patients. There are few data outside clinical trials evaluating their prevalence and impact of elbasvir/grazoprevir. A multicenter cross-sectional study of 617 HCV-GT1a-infected individuals attended in 84 Spanish hospitals from the 17 Autonomous Communities and two Autonomous cities was performed. HCV population sequencing was used to identify RASs to elbasvir and the mutational pattern and drug sensitivity were confirmed by geno2pheno[HCV]. Viruses bearing RASs to elbasvir were present in 6.2% of HCV-GT1a infected patients. The most common RASs were the Y93C/H/N and Q30E/H/R (2.4% and 2.3%; respectively). Only 3.4% of patients had viruses with RASs that confer reduced susceptibility to elbasvir by geno2pheno[HCV] that identified exclusively the positions Q30H/R (n = 7) and Y93C/H/N (n = 8) as single mutations and Q30H + Y93H (n = 4) and Q30R + Y93H (n = 2) as double mutations considered as RASs to elbasvir. Lower prevalence of RASs to elbasvir in our HCV-GT1a-Spanish cohort was observed than reported previously in clinical trials. This information may be essential to guiding the implementation of elbasvir/grazoprevir in Spain, expected at the beginning of 2017 and the management of GT1a-infected patients.

Off-label use of rilpivirine in combination with emtricitabine and tenofovir in HIV-1-infected pediatric patients: A multicenter study.

To assess the safety and efficacy of rilpivirine in combination with emtricitabine and tenofovir (RPV/FTC/TDF) as a once-daily single-tablet regimen (STR) in HIV-1-infected children and adolescents we performed a multicenter case series study of HIV-1-infected patients. Inclusion criteria were initiation of therapy with RPV/FTC/TDF before the age of 18. Patients were divided into undetectable viral load (uVL) group, HIV-1 RNA < 20 copies/mL on stable combined antiretroviral therapy (cART), and detectable viral load (dVL) group, HIV-1 RNA ≥ 20 copies/mL at RPV/FTC/TDF initiation. Patients were monitored from the date of RPV/FTC/TDF initiation until June 30, 2015, RPV/FTC/TDF discontinuation or failure to follow-up. Seventeen patients (8 in uVL and 9 in dVL group) with age between 11.6 and 17.6 were included. Reasons for switching were toxicity (n = 4) and simplification (n = 4) in uVL; viral failure (n = 8) and cART initiation (n = 1) in the dVL group. After a median follow-up of 90 (uVL) and 40 weeks (dVL), 7/8 (86%) patients maintained and 8/9 (89%) achieved and maintained HIV-1 suppression. Median CD4 count increased from 542 to 780/µL (uVL, P = 0.069) and 480 to 830/µL (dVL, P = 0.051). Five patients (2 in uVL and 3 in dVL) improved their immunological status from moderate to no immunosuppression. Serum lipid profiles improved in both groups; cholesterol dropped significantly in the dVL group (P = 0.008). Grade 1 laboratory adverse events (AEs) were observed in 3 patients. No clinical AEs occurred. Adherence was complete in 9 patients (5 in uVL and 4 in dVL); 1 adolescent interrupted treatment. Once-daily STR with RPV/FTC/TDF may be a safe and effective choice in selected HIV-1-infected adolescents and children.

A Conserved GPG-Motif in the HIV-1 Nef Core Is Required for Principal Nef-Activities.

To find out new determinants required for Nef activity we performed a functional alanine scanning analysis along a discrete but highly conserved region at the core of HIV-1 Nef. We identified the GPG-motif, located at the 121-137 region of HIV-1 NL4.3 Nef, as a novel protein signature strictly required for the p56Lck dependent Nef-induced CD4-downregulation in T-cells. Since the Nef-GPG motif was dispensable for CD4-downregulation in HeLa-CD4 cells, Nef/AP-1 interaction and Nef-dependent effects on Tf-R trafficking, the observed effects on CD4 downregulation cannot be attributed to structure constraints or to alterations on general protein trafficking. Besides, we found that the GPG-motif was also required for Nef-dependent inhibition of ring actin re-organization upon TCR triggering and MHCI downregulation, suggesting that the GPG-motif could actively cooperate with the Nef PxxP motif for these HIV-1 Nef-related effects. Finally, we observed that the Nef-GPG motif was required for optimal infectivity of those viruses produced in T-cells. According to these findings, we propose the conserved GPG-motif in HIV-1 Nef as functional region required for HIV-1 infectivity and therefore with a potential interest for the interference of Nef activity during HIV-1 infection.

Off-label use of maraviroc in HIV-1-infected paediatric patients in clinical practice.

Maraviroc (MVC) is not approved for HIV-1-infected paediatric patients. This is the first assessment of the use of MVC-based salvage therapy in vertically HIV-1-infected paediatric patients in clinical settings. The results suggest that MVC-based salvage therapy is useful in children and adolescents with extensive resistance profile leading to maintained virological suppression in up to 88% of the patients with CCR5-tropic virus. The likelihood of treatment success might increase when MVC is combined with other active drugs.

HIV-1 diversity, transmission dynamics and primary drug resistance in Angola.

OBJECTIVES: To assess HIV-1 diversity, transmission dynamics and prevalence of transmitted drug resistance (TDR) in Angola, five years after ART scale-up. METHODS: Population sequencing of the pol gene was performed on 139 plasma samples collected in 2009 from drug-naive HIV-1 infected individuals living in Luanda. HIV-1 subtypes were determined using phylogenetic analysis. Drug resistance mutations were identified using the Calibrated Population Resistance Tool (CPR). Transmission networks were determined using phylogenetic analysis of all Angolan sequences present in the databases. Evolutionary trends were determined by comparison with a similar survey performed in 2001. RESULTS: 47.1% of the viruses were pure subtypes (all except B), 47.1% were recombinants and 5.8% were untypable. The prevalence of subtype A decreased significantly from 2001 to 2009 (40.0% to 10.8%, P = 0.0019) while the prevalence of unique recombinant forms (URFs) increased > 2-fold (40.0% to 83.1%, P < 0.0001). The most frequent URFs comprised untypable sequences with subtypes H (U/H, n = 7, 10.8%), A (U/A, n = 6, 9.2%) and G (G/U, n = 4, 6.2%). Newly identified U/H recombinants formed a highly supported monophyletic cluster suggesting a local and common origin. TDR mutation K103N was found in one (0.7%) patient (1.6% in 2001). Out of the 364 sequences sampled for transmission network analysis, 130 (35.7%) were part of a transmission network. Forty eight transmission clusters were identified; the majority (56.3%) comprised sequences sampled in 2008-2010 in Luanda which is consistent with a locally fuelled epidemic. Very low genetic distance was found in 27 transmission pairs sampled in the same year, suggesting recent transmission events. CONCLUSIONS: Transmission of drug resistant strains was still negligible in Luanda in 2009, five years after the scale-up of ART. The dominance of small and recent transmission clusters and the emergence of new URFs are consistent with a rising HIV-1 epidemics mainly driven by heterosexual transmission.

Determinants of highly active antiretroviral therapy duration in HIV-1-infected children and adolescents in Madrid, Spain, from 1996 to 2012.

OBJECTIVES: To investigate the duration of sequential HAART regimens and predictors of first-line regimen discontinuation among HIV-1 vertically infected children and adolescents. DESIGN: Multicentre survey of antiretroviral-naïve patients enrolled in the HIV-Paediatric Cohor,t CoRISpeS-Madrid Cohort, Spain. METHODS: Patients with a follow-up of ≥ 1 month spent on HAART, with available baseline CD4 count and HIV-viral load (VL) were included. Time spent on sequential HAART regimens was estimated and multivariable regression was used to identify predictors of time to first-line regimen discontinuation. RESULTS: 104 patients were followed for a median 8 years after starting HAART among 1996-2012; baseline %CD4 was 21.5 (12.3-34.0)and viral load was 5.1 (4.6-5.6) log10 copies/mL. Patients received a mean of 1.9 regimens. Median time on first-line HAART (n = 104) was 64.5 months; second HAART (n = 56) 69.8 months; and third HAART (n = 21) 66.5 months. Eleven (11%) patients were lost to follow-up while on first-line HAART and 54% discontinued (cumulative incidence of 16% and 38% by 1 and 3-year, respectively). The main predictor of first-line regimen discontinuation was suboptimal adherence to antiretrovirals (AHR: 2.60; 95% CI: 1.44-4.70). CONCLUSIONS: Adherence to therapy was the main determinant of the duration of the first-line HAART regimen in children. It is important to identify patients at high risk for non-adherence, such as very young children and adolescents, in provide special care and support to those patients.

Predictors of attrition and immunological failure in HIV-1 patients on highly active antiretroviral therapy from different healthcare settings in Mozambique.

In Mozambique, the evaluation of retention in HIV care and ART programmes is limited. To assess rate and predictors of attrition (no retention in care) and HAART effectiveness in HIV-1 infected patients who pay for medication and laboratory testing in Mozambique, we conducted a multicenter survey of HIV-1-infected patients who started HAART during 2002-2006. Cox proportional hazard models were used to assess risk of attrition and of therapy failure. Overall, 142 patients from 16 healthcare centers located in the capital city Maputo were followed-up for 22.2 months (12.1-46.7). The retention rate was 75%, 48% and 37% after one, two and three years, respectively. Risk of attrition was lower in patients with higher baseline CD4 count (P = 0.022) and attending healthcare center 1 (HCC1) (P = 0.013). The proportion of individuals with CD4 count ≤ 200 cells/µL was 55% (78/142) at baseline and decreased to 6% (3/52) at 36 months. Among the patients with available VL, 86% (64/74) achieved undetectable VL levels. The rate of immunologic failure was 17.2% (95% CI: 12.6-22.9) per 100 person-years. Risk of failure was associated to higher baseline CD4 count (P = 0.002), likely reflecting low adherence levels, and decreased with baseline VL ≥ 10,000 copies/mL (P = 0.033). These results suggest that HAART can be effective in HIV-1 infected patients from Mozambique that pay for their medication and laboratory testing. Further studies are required to identify the causes for low retention rates in patients with low CD4 counts and to better understand the association between healthcare setting and attrition rate.

Potent and sustained antiviral response of raltegravir-based highly active antiretroviral therapy in HIV type 1-infected children and adolescents.

BACKGROUND: There are pediatric patients receiving many highly active antiretroviral therapy (HAART) regimens entailing drug resistance mutations that complicate HAART effective therapies. METHODS: This was a multicenter retrospective study of 19 multidrug-resistant children and adolescents enrolled from July 2007 to October 2009. Patients were nonresponders because no reduction in HIV type 1 (HIV-1) RNA to undetectable levels was observed during their previous antiretroviral treatment history. The long-term effectiveness of raltegravir (RAL)-based salvage therapy was assessed through a longitudinal analysis of immunologic, virologic, and clinical status of the patients. RESULTS: Median age was 16.0 (15.0-18.0) years. At baseline, median HIV-1 RNA was 10,000 (4.0 log10 copies/mL) (interquartile range [IQR]: 4300-83,000), and median CD4T-cell count was 329 (18.2% cells/µL) (IQR: 175-452). The backbone regimen included at least 1 fully active drug in 17/19 (89%) patients. Median follow-up with HAART including RAL was 80.1 weeks (IQR: 49.4-96.4): 16/19 (84%) exposed for >120 weeks and 6/19 (32%) >100 weeks. After RAL-based therapy, 4/19 (21%) patients achieved HIV-1 RNA <400 copies and 13/17 (68%) reached HIV-1 RNA <50 copies: 6 (32%) within the first month and 7 (37%) within the first 4 months. CD4+ T-cell recovery (70% to 90% of the baseline values) was observed in 17/19 (89%) patients. No deaths, AIDS-defining illnesses, or symptoms of severe intolerance were recorded. Only 2 patients experienced mild-moderate short-term skin rash. Two (11%) patients had sustained and optimum adherence to HAART. No patients showed resistance mutations to RAL after follow-up. CONCLUSIONS: We observed a sustained antiviral response and improved immunologic indices in multidrug-resistant pediatric patients, most of whom had received RAL as part of salvage regimens with at least 1 fully active drugs.

Evaluation of the diagnostic performance of the rapid test VIKIA HIV1/2 in a highly complex HIV-1 epidemic.

The rapid test VIKIA HIV1/2 was evaluated in 210 Angolan subjects infected with multiple HIV-1 subtypes and complex recombinant forms and 225 seronegative individuals. All infected subjects tested positive (100% sensitivity); all seronegative subjects tested negative (100% specificity). VIKIA HIV1/2 is highly specific and sensitive even in highly complex epidemics.