High Propensity to Switch to Long-acting Injectable HIV PrEP with Cabotegravir in a Cohort of Oral PrEP Experienced Men who Have Sex with Men in Italy.

Aim was to investigate the propensity to switch to long-acting injectable HIV pre-exposure prophylaxis (PrEP) with cabotegravir among oral PrEP-experienced men who have sex with men. Out of 377 PrEP users, 325 (86.2%) were interested (would like = 210) or considering (would consider = 115) switch to long-acting PrEP. At multivariable analysis, the odds ratio of interest in long-acting PrEP in non-adherent vs. adherent individuals to oral PrEP was 5.03 (95%CI = 1.73-14.61,p = 0.003) and of consideration 1.63 (95%CI = 0.51-5.23,p = 0.410). We observed very high propensity to switch to long-acting PrEP, particularly among non-adherent users. Rapid availability of long-acting PrEP might address unmet needs of PrEP users in Italy.

Mpox DNA clearance in semen over 6-month follow-up.

Sexual intercourse is a well-established way of transmission of mpox infection. However, it is still uncertain whether semen may represent a viral reservoir. The aim of the study was to evaluate the clearance of viral DNA in semen samples from individuals diagnosed with mpox infection over 6-month follow-up. This prospective, observational, single-center study was conducted at IRCCS San Raffaele Scientific Institute, Milan, Italy, between May and October 2022 in 140 individuals who attended Sexual Health Clinic and diagnosed with mpox infection. Semen samples were collected and analyzed by real-time polymerase chain reaction assays. The baseline collection was performed in 64 (46%) of 140 men diagnosed with mpox infection. The viral DNA was detected in 43 (67%) with median cycle threshold (Ct) 34 (interquartile range [IQR] 31-36). The research was repeated in 32 (74%) and viral DNA clearance was observed in all within 6 months in a median time of 10.5 days (IQR 7-33). Viral clearance occurred in all tested individuals, mostly within 2 weeks since the first positive test. These findings suggest a transient presence of viral DNA in semen and do not support the hypothesis of reservoir. More studies on mpox DNA detection in semen with viral culture and extended follow-up are needed.

Association of high-risk sexual behaviours with sexually transmitted infections among men who have sex with men living with HIV.

OBJECTIVES: To explore different sexual behaviours as risk factors for STI among men who have sex with men (MSM) living with HIV. METHODS: This is a cross-sectional study on MSM living with HIV followed at the Infectious Diseases Unit of San Raffaele Hospital, Milan, with at least one diagnosis of gonorrhoea, syphilis, chlamydia or anal human papilloma virus (HPV), between July 2016 and February 2021. We conducted a survey on high-risk sexual behaviours with regard to (1) mean number of partners per month, (2) estimated percentage of condom use and (3) most frequent type of sexual intercourse during 2016-2021. Data on these variables were grouped as follows: (1a) ≤5 vs >5, (1b) >10 vs ≤10, (2a) 0% vs >0%, (2b) ≤50% vs >50%, (2c) 100% vs <100%, (3a) ≥50% vs <50% receptive, (3b) 100% vs <100% insertive, and (3c) 100% vs <100% receptive. A high-risk group was defined as >5 partners, <100% use of condom and ≥50% receptive intercourse. Univariate logistic regressions were applied to assess the association between sexual behaviours and the risk of each STI. RESULTS: Out of 1051 MSM with at least one STI diagnosis, 580 (55%) answered the survey. The risk of chlamydia was lower among individuals with ≤5 partners (≤5 partners vs >5 partners: OR=0.43, 95% CI 0.28 to 0.66, p=0.001) and among those using condoms more frequently (≤50% use of condom vs >50% use of condom: OR=1.55, 95% CI 1.06 to 2.27, p=0.025; 100% vs <100%: OR=0.35, 95% CI 0.20 to 0.59, p=0.001). Individuals using condoms more frequently also had lower risk of gonorrhoea (100% use of condom vs <100% use of condom: OR=0.37, 95% CI 0.17 to 0.79, p=0.011). The risks of chlamydia (OR=3.07, 95% CI 1.92 to 4.90, p<0.001) and gonorrhoea (OR=2.05, 95% CI 1.12 to 3.75, p=0.020) were higher among individuals belonging to the high-risk group. CONCLUSIONS: Chlamydia and gonorrhoea are more likely associated with high-risk sexual behaviours than syphilis and anal HPV among MSM living with HIV.

Meningococcus B Vaccination Effectiveness Against Neisseria gonorrhoeae Infection in People Living With HIV: A Case-Control Study.

BACKGROUND: We assessed the vaccination effectiveness (VE) of multicomponent meningococcal serogroup B (4CMenB) vaccine against gonorrhea among people living with HIV (PLWH) with a previous diagnosis of sexually transmitted infection. METHODS: Unmatched case-control study on men who have sex with men living with HIV, in care at San Raffaele Scientific Institute, Milan, Italy, with gonorrhea, syphilis, chlamydia, or anal human papillomavirus between July 2016 (beginning of 4CMenB vaccination) and February 2021 (date of freezing). For the analysis, cases were people with ≥1 gonorrhea infection since July 2016, and controls were people with ≥1 syphilis, chlamydia, or anal human papillomavirus infection since July 2016. Logistic regression was used to provide the estimate of 4CMenB VE against gonorrhea. RESULTS: Included people living with HIV were 1051 (103 cases, 948 controls); 349 of 1051 (33%) received 2 doses of 4CMenB vaccination. The median follow-up was 3.8 years (2.1-4.3 years). The unadjusted estimate for VE against gonorrhea was 42% (95% confidence interval, 6%-64%; P = 0.027). Logistic regression showed that VE against gonorrhea remained significant (44%; 95% confidence interval, 9%-65%; P = 0.020) after adjusting for some factors that might have a potential influence on VE or those with significant unbalanced distributions between cases and controls at univariable analysis. CONCLUSIONS: 4CMenB vaccination is associated with a lower risk of gonorrhea in the setting of men who have sex with men living with HIV with a previous sexually transmitted infection.

Pillars of long-term antiretroviral therapy success.

BACKGROUND: Meeting the challenge of antiretroviral therapy (ART) whose efficacy can last a lifetime requires continuous updating of the virological, pharmacological, and quality of life outcomes to be pursued and a continuous review of literature data on the efficacy and tolerability of new drugs and therapeutic strategies. METHODS: With the aim of identifying open questions and answers about the current controversies in modern ART, we adapted the Design Thinking methodology to the needs of the design phase of a scientific article, involving a team of experts in HIV care. RESULTS: Five main pillars of treatment success were discussed: sustained virologic suppression over time; immunological recovery; pharmacological attributes; long-term tolerability and safety of ART; and people's satisfaction and quality of life. The definition of the outcomes to be achieved in each thematic area and the tools to achieve them were reviewed and discussed. CONCLUSIONS: Long-term treatment success should be intended as a combination of HIV-RNA suppression, immune recovery, and high quality of life. To achieve this, the regimen should be well-tolerated, with high potency, genetic barrier, and forgiveness, and should be tailored by a person-centered perspective, based on individual needs, preferences, and therapeutic history.

No need to modify treatment within the first month after rapid start of a tailored antiretroviral therapy: the TWODAY Study.

The aim of the TWODAY Study was to investigate the frequency of early treatment change after rapid start of a tailored ART regimen (a 2-drug regimen - 2DR, when clinically feasible or a 3-drug regimen - 3DR, otherwise). TWODAY was an open-label, prospective, proof-of-concept, single center study. ART-naïve patients started their first-line regimen within a few days from the first laboratory testing with a 2DR of dolutegravir (DTG) and lamivudine (3TC) if CD4+ count >200 cells/mL, HIVRNA <500,000 copies/mL, no transmitted drug resistance to DTG or 3TC and HBsAg undetectable; otherwise, ART was started with a 3DR. The primary endpoint was the proportion of patients who needed to change ART within four week from start, for any reason. Thirty-two patients were enrolled; 19 (59.3%) were deemed eligible for a 2DR. Median time from laboratory testing to ART start was 5 days (5; 5). No regimen modification occurred within one month. In conclusion, no regimen modification was needed within the first month of treatment. Starting a 2DR within a few days after HIV diagnosis was feasible, relying upon complete results of the needed laboratory tests (including resistance testing). A 2DR can be safely proposed provided full laboratory tests are readily available.

Development of the HIV360 international core set of outcome measures for adults living with HIV: A consensus process.

OBJECTIVES: HIV outcomes centre primarily around clinical markers with limited focus on patient-reported outcomes. With a global trend towards capturing the outcomes that matter most to patients, there is agreement that standardizing the definition of value in HIV care is key to their incorporation. This study aims to address the lack of routine, standardized data in HIV care. METHODS: An international working group (WG) of 37 experts and patients, and a steering group (SG) of 18 experts were convened from 14 countries. The project team (PT) identified outcomes by conducting a literature review, screening 1979 articles and reviewing the full texts of 547 of these articles. Semi-structured interviews and advisory groups were performed with the WG, SG and people living with HIV to add to the list of potentially relevant outcomes. The WG voted via a modified Delphi process - informed by six Zoom calls - to establish a core set of outcomes for use in clinical practice. RESULTS: From 156 identified outcomes, consensus was reached to include three patient-reported outcomes, four clinician-reported measures and one administratively reported outcome; standardized measures were included. The WG also reached agreement to measure 22 risk-adjustment variables. This outcome set can be applied to any person living with HIV aged > 18 years. CONCLUSIONS: Adoption of the HIV360 outcome set will enable healthcare providers to record, compare and integrate standardized metrics across treatment sites to drive quality improvement in HIV care.

HIV-DNA undetectability during chronic HIV infection: frequency and predictive factors.

BACKGROUND: HIV-DNA is a marker of HIV reservoirs. Objectives of the study were to determine prevalence of HIV-DNA < 100 copies/106 PBMCs in blood and to identify factors associated with this in a cohort of HIV-1-infected subjects treated with ART and with undetectable viral load (VL). METHODS: This was a cross-sectional study on chronic HIV-1-infected people living with HIV (PLWH) followed up at the Department of Infectious Diseases of San Raffaele Scientific Institute on current ART without change for 12 months, with available pre-ART HIV-RNA and with undetectable VL for ≥12 months. HIV-DNA was amplified and quantified by real-time PCR (ABI Prism 7900); limit of detectability was 100 copies/106 PBMCs. Logistic regression was used to identify predictive factors for HIV-DNA < 100 copies/106 PBMCs. RESULTS: Four hundred and sixty-eight PLWH were considered in the analyses, 119 (25%) with HIV-DNA < 100 copies/106 PBMCs. At multivariate analysis, we found that PLWH with lower zenith HIV-RNA, higher nadir CD4 and a shorter time between HIV diagnosis and ART start were more likely to have HIV-DNA < 100 copies/106 PBMCs, after adjustment for age, gender, calendar year of ART start, type of current ART regimen, percentage time spent with undetectable VL since ART start, current CD4 and CD4/CD8 ratio. CONCLUSIONS: In our chronic PLWH on virological suppression for 4 years, the prevalence of HIV-DNA < 100 copies/106 PBMCs was found to be 25%. Lower zenith HIV-RNA, shorter time between HIV diagnosis and starting ART and higher CD4 nadir were independently associated with low HIV-DNA.

Impact of NRTI resistance mutations on virological effectiveness of antiretroviral regimens containing elvitegravir: a multi-cohort study.

BACKGROUND: Antiretroviral drug resistance mutations remain a major cause of treatment failure. OBJECTIVES: To evaluate the impact of NRTI resistance mutations on virological effectiveness of elvitegravir-containing regimens. MATERIALS AND METHODS: We selected treatment-experienced HIV-1-infected patients starting elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF), with at least one protease/reverse transcriptase genotype available before switching and at least one HIV-1 RNA viral load (VL) measurement during follow-up. The primary endpoint was virological failure (VF), defined as one VL value of ≥1000 copies/mL or two consecutive VL values of >50 copies/mL. RESULTS: We included 264 ART regimens: 75.6% male, median (IQR) age 47 years (39-53), 7 years (3-16) of HIV infection, nadir CD4+ 247 cells/mm3 (105-361), 81.5% with VL ≤50 copies/mL and 11.7% with at least one NRTI mutation at baseline. Eleven (5.2%) VFs occurred in virologically suppressed patients versus eight (15.1%) in viraemic patients. The estimated probability of VF at 48 weeks with versus without any NRTI mutation was 7.4% (95% CI 2.3-12.5) versus 3.8% (2.1-5.5) in virologically suppressed patients and 66.7% (39.5-93.9) versus 11.2% (6.5-15.9) (P<0.001) in viraemic patients. The only predictor of VF was time on therapy (per 1 year more, adjusted HR 1.14, 95% CI 1.02-1.27, P=0.024) in viraemic patients. CONCLUSIONS: A switch to E/C/F/TDF or E/C/F/TAF is safe for virologically suppressed patients without documented NRTI resistance, but not recommended in viraemic patients with a history of NRTI resistance. Although we did not detect a detrimental effect of past NRTI resistance in virologically suppressed patients, a fully active regimen remains preferred in this setting due to possible rebound of drug-resistant virus in the long term.

Relapse of Symptomatic Cerebrospinal Fluid HIV Escape.

PURPOSE OF REVIEW: Symptomatic cerebrospinal fluid (CSF) HIV escape defines the presence of neurological disease in combination antiretroviral therapy (cART)-treated persons due to HIV replication in CSF despite systemic suppression or to higher viral replication in CSF than in plasma. The aim was to search for cases of recurrent symptomatic CSF escape and to define their characteristics. RECENT FINDINGS: By review of the literature, we identified symptomatic CSF escape relapses in three patients who had shown clinical remission of a first escape episode following cART optimization. By examination of our cohort of 21 patients with symptomatic CSF escape, we identified five additional patients. In the latter, viral escape relapsed over a median follow-up of 108 months because of low adherence or upon treatment simplification of a previously optimized regimen. cART reoptimization based on resistance profile and potential drug neuropenetration and efficacy led to relapse resolution with no further episodes after a median follow-up of 50 months from relapse. The observation that CSF escape may relapse highlights the importance of long-term neuro-suppressive regimens after a first episode and supports the role of the brain as a reservoir for HIV.

Durability of first-line regimens including integrase strand transfer inhibitors (INSTIs): data from a real-life setting.

OBJECTIVES: To evaluate the durability of three integrase strand transfer inhibitors (INSTIs) and two NRTIs in ART-naive individuals. METHODS: The study design was observational. Patients were HIV-positive, ART-naive subjects starting raltegravir, elvitegravir/cobicistat or dolutegravir with two NRTIs. The primary endpoint was time to treatment failure, i.e. occurrence of virological failure (first of two consecutive plasma HIV RNAs ≥200 copies/mL after 24 weeks) or INSTI discontinuation for any reason apart from simplification. Secondary endpoints were INSTI discontinuation due to toxicity/intolerance and CD4 count response. Survival analysis was done using Kaplan-Meier and Cox regression. RESULTS: Two thousand and sixteen patients were included: 310 (15.4%) started raltegravir-based regimens, 994 (49.3%) started dolutegravir-based regimens and 712 (35.3%) started elvitegravir/cobicistat-based regimens. Over a median of 11 months, 167 patients experienced treatment failure; the 1 year probability of treatment failure was 6.5% for raltegravir, 5.4% for dolutegravir and 6.7% for elvitegravir/cobicistat (P = 0.001). Sixty-eight patients (3.4%) discontinued INSTIs owing to toxicity/intolerance. By multivariable analysis, patients starting raltegravir had a 2.03-fold (95% CI = 1.2-3.2) higher risk and patients on elvitegravir/cobicistat a 1.88-fold (95% CI = 1.2-2.9) higher risk of treatment failure versus dolutegravir; there was no difference in risk of discontinuation due to toxicity/intolerance when comparing dolutegravir and raltegravir and marginal evidence for a difference when comparing elvitegravir/cobicistat and dolutegravir (adjusted relative hazard = 1.94 for elvitegravir/cobicistat versus dolutegravir, 95% CI = 1.00-3.76, P = 0.05). CONCLUSIONS: In our real-life setting, INSTI-based regimens showed high potency and durability. Among regimens currently recommended in Europe, those including dolutegravir are associated with a lower risk of treatment failure.

Durability of different initial regimens in HIV-infected patients starting antiretroviral therapy with CD4+ counts <200 cells/mm3 and HIV-RNA >5 log10 copies/mL.

OBJECTIVES: Our aim was to investigate the durability of different initial regimens in patients starting ART with CD4+ counts <200 cells/mm3 and HIV-RNA >5 log10 copies/mL. METHODS: This was a retrospective study of HIV-infected patients prospectively followed in the ICONA cohort. Those who started ART with boosted protease inhibitors (bPIs), NNRTIs or integrase strand transfer inhibitors (InSTIs), with CD4+ <200 cells/mm3 and HIV-RNA >5 log10 copies/mL, were included. The primary endpoint was treatment failure (TF), a composite endpoint defined as virological failure (VF, first of two consecutive HIV-RNA >50 copies/mL after 6 months of treatment), discontinuation of class of the anchor drug or death. Independent associations were investigated by Poisson regression analysis in a model including age, gender, mode of HIV transmission, CDC stage, HCV and HBV co-infection, pre-treatment HIV-RNA, CD4+ count and CD4+/CD8+ ratio, ongoing opportunistic disease, fibrosis FIB-4 index, estimated glomerular filtration rate, haemoglobin, platelets, neutrophils, calendar year of ART initiation, anchor drug class (treatment group) and nucleos(t)ide backbone. RESULTS: A total of 1195 patients fulfilled the inclusion criteria: 696 started ART with a bPI, 315 with an InSTI and 184 with an NNRTI. During 2759 person-years of follow up, 642 patients experienced TF. Starting ART with bPIs [adjusted incidence rate ratio (aIRR) (95% CI) 1.62 (1.29-2.03) versus starting with NNRTIs; P < 0.001] and starting ART with InSTIs [aIRR (95% CI) 0.68 (0.48-0.96) versus starting with NNRTIs; P = 0.03] were independently associated with TF. CONCLUSIONS: In patients starting ART with <200 CD4+ cells/mm3 and >5 log10 HIV-RNA copies/mL, the durability of regimens based on InSTIs was longer than that of NNRTI- and bPI-based regimens.

Homeostatic model assessment for insulin resistance index trajectories in HIV-infected patients treated with different first-line antiretroviral regimens.

OBJECTIVE: To describe the trajectories of the homeostatic model assessment for insulin resistance (HOMA-IR) index in a cohort of HIV-1 infected patients during their first-line antiretroviral (ART) regimen. METHODS: Retrospective analysis of naïve patients who started ART from 2007 at the Infectious Diseases Unit of the San Raffaele Hospital, Milan. We included patients treated with two nucleoside reverse transcriptase inhibitors (NRTIs, tenofovir, abacavir, lamivudine or emtricitabine), and one anchor drug (ritonavir-boosted protease inhibitor [PI/r], non-NRTI [NNRTI], or integrase strand transfer inhibitor [InSTI]), and with HOMA-IR assessed both before and after the start of ART. Univariate and multivariate mixed linear models estimated HOMA-IR changes during ART. RESULTS: Among 618 patients included in the study, 218 received InSTI-, 210 PI/r-, and 190 NNRTI-based regimens. Median follow-up was 27.4 (16.3-41.2) months. Adjusted mean change in HOMA-IR index was significantly higher (P = .041) in patients treated with InSTI-based regimens [0.160 (95% CI: 0.003-0.321) units per year] compared with NNRTI-based regimens [-0.005 (95% CI: -0.184-0.074) units per year]; no difference was observed between patients treated with NNRTI- and PI/r-based regimens or between INSTI-based and PI/r-based regimens. CONCLUSION: InSTI-based first-line ARTs were independently associated with greater increases in HOMA-IR index.

Pre-ART HIV-1 DNA in CD4+ T cells correlates with baseline viro-immunological status and outcome in patients under first-line ART.

Objectives: We evaluated the association between pre-ART HIV DNA and HIV-infected participant characteristics at baseline as well as with their response to first-line ART. Methods: Four hundred and thirty-three patients from the ICONA cohort, starting first-line ART after the year 2000, were analysed. Pre-ART HIV DNA was quantified with the modified COBAS TaqMan HIV-1 Test and normalized by CD4+ T cells. Linear correlation between pre-ART HIV DNA and other continuous markers (HIV RNA, CD4 count, markers of inflammation and coagulation) at baseline was evaluated by means of Pearson correlation coefficient and a linear regression model. Survival analyses and Cox regression models were used to study the association between pre-ART HIV DNA and time to viro-immunoclinical events. Results: Pre-ART HIV DNA [median (IQR): 10 702 (3397-36 632) copies/106 CD4+ T cells] was correlated with pre-ART HIV RNA [R2 = +0.44, (P < 0.0001)], CD4+ T cells [R2 = -0.58, (P < 0.0001)] and CD4/CD8 ratio [R2 = -0.48, (P < 0.0001)], while weaker correlations were observed with CD8+ T cells (R2 = -0.20, P = 0.01), IL-6 (R2 = +0.16, P = 0.002) and soluble CD14 (R2 = +0.09, P = 0.05). Patients with higher pre-ART HIV DNA showed lower rate and delayed virological response (defined as HIV RNA ≤50 copies/mL), compared with those having lower HIV DNA (67.2% for >10 000, 81.1% for 1000-10 000 and 86.4% for 10-1000 copies/106 CD4+ T cells; P = 0.0004). Higher pre-ART HIV DNA was also correlated with increased risk of virological rebound (defined as HIV RNA >50 copies/mL) by 24 months (17.2% for >10 000, 7.4% for 1000-10 000 and 4.3% for 10-1000 copies/106 CD4+ T cells; P = 0.0048). Adjusted HRs of all virological rebound definitions confirmed these findings (P ≤ 0.02). Conclusions: Pre-ART HIV DNA, along with HIV RNA and CD4+ T cell count, should be considered as a new staging marker to better identify people at lower (or higher) risk of viral rebound following achievement of virological suppression (≤50 copies/mL).

Glomerular filtration rate estimated by cystatin C formulas in HIV-1 patients treated with dolutegravir, rilpivirine or cobicistat.

As dolutegravir (DTG), rilpivirine (RPV) and cobicistat affect creatinine, but not cystatin C, tubular transport or serum concentration, the aim of the study was to compare estimated glomerular filtration rates (eGFRs) calculated by means of a standard creatinine formula with those calculated by means of the cystatin C formula in patients receiving these drugs. This was a cross-sectional study of HIV-1 infected patients with eGFR <90 ml/min/1.73 m2 (CKD-EPI-creatinine formula) on-treatment with regimens including DTG, RVP or cobicistat; cystatin C was measured after the switch to these regimens. eGFR was calculated by means of the CKD-EPI formulas (CKD-EPI-creatinine: eGFRcrea; CKD-EPI-cystatin C: eGFRcyst). eGFRcyst was compared with the last eGFR assessed before (eGFRcrea pre) and after the switch (eGFRcrea post). The primary end-point of the study was the difference between eGFRcyst and eGFRcrea post. One hundred and twenty patients were included. eGFRcrea pre was 80 (70-92) ml/min/1.73 m2. eGFRcrea post was significantly lower than eGFRcyst (65 [59-75] vs. 80 [69-95] mL/ min/1.73m2; p<0.001); eGFRcyst did not differ from eGFRcrea pre (p=0.544). The difference between eGFRcyst and eGFRcrea post was not significantly different among regimen groups (p=0.056). In HIV-patients with reduced eGFR treated with DTG, RPV or cobicistat, measuring eGFR by means of the CKD-EPI cystatin C formula is probably more relevant.

Evidence-based renewal of the Italian guidelines for the use of antiretroviral agents and the diagnostic-clinical management of HIV-1 infected persons.

The Italian Society for Infectious and Tropical Diseases (SIMIT) in collaboration with the Technical Health Committee (Sections L and M) of the Italian Ministry of Health have supported the renewal of the recommendations for the Italian guidelines for the use of antiretroviral agents and the diagnostic-clinical management of HIV-1 infected persons. This publication summarizes the latest updates to the 2017 version of the Italian Guidelines for the management of HIV-1 infected patients and the use of antiretroviral drugs. New recommendations were released framing the clinical questions the use of antiretrovirals according to the Patient Intervention Comparator Outcome (PICO) methodology and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Diagnostic tools for immunological and virological monitoring, when to start, what to start, optimization and therapeutic failure were updated in order to include the recommendation obtained with these newly developed methods. For a complete review of clinical and therapeutic relevant topics we refer the reader to the extended version of the Guidelines.

Efficacy and tolerability of switching to a dual therapy with darunavir/ritonavir plus raltegravir in HIV-infected patients with HIV-1 RNA ≤50 cp/mL.

BACKGROUND: Nucleos(t)ide reverse transcriptase inhibitors (NRTI) toxicity may represent a threat for long-term success of combined antiretroviral therapy. Some studies have suggested a possible improvement of NRTI-related toxicity after switching to NRTI-sparing regimens. OBJECTIVES: We aimed to explore the efficacy and tolerability of switching to darunavir/ritonavir (DRV/r) plus raltegravir (RAL) while having a viral load (VL) ≤50 copies/mL in the clinical setting. STUDY DESIGN: Treatment-experienced HIV 1-infected patients enrolled in the ICONA Foundation Study cohort were included if they switched their current regimen to DRV/r + RAL with a HIV-RNA ≤50 copies/mL. Different definitions of virological failure (VF) and treatment failure (TF) were employed. Kaplan-Meier curves and Cox regression models were performed to estimate time to event probability. RESULTS: We included 72 HIV-infected patients, 22 (31%) of these were female, 31 (43%) men who have sex with men (MSM) amd 15 (21%) had hepatitis co-infections. Median age was 44 (IQR: 35-50) years amd CD4 count was 389 (IQR 283-606) cells/mmc. Median follow-up time for TF was 24 (IQR 9-31) months. Twenty-five discontinuations occurred (60% simplifications); only 2 (8%) were toxicity-driven (lipid elevations). The probability of VF (confirmed VL >50 copies/mL) was estimated at 7% [95% confidence interval (CI) 1-13%] by 12 and 9% (95% CI 2-16%) by 24 months. When considering TF, we found a probability of stop/intensification/single VL > 200 copies/mL of 13% (95% CI 1-17%) and 22% (95% CI 11-33%) by 12 and 24 months. Female gender (adjusted relative hazard, ARH = 0.10; 95% CI 0.01-0.74; p = 0.024) and older age (AHR = 0.50 per 10 years older; 95% CI 0.25-0.99; p = 0.045) were associated with a lower risk of TF. A previous PI failure was strongly associated with TF (AHR = 52.6, 95% CI 3.6-779; p = 0.004). CONCLUSIONS: DRV/r + RAL is a valuable NRTI-sparing option, especially in female and older patients, with a relatively low risk of VF and good tolerability after 2 years since start in an ART-experienced population. However, previous PI-failure should be a limiting factor for this strategy.