Reversibility of Neuropsychiatric Adverse Events after Switching to Darunavir/Cobicistat or Doravirine in Men on INSTI-Based Regimen.

Integrase strand transfer inhibitors (INSTI) are associated with neuropsychiatric adverse events (NPAEs). The aim of this study was to evaluate improvements in NPAEs after switching an INSTI-based regimen to darunavir/cobicistat (DRV/c) or doravirine (DOR). Methods: A prospective cohort study was conducted to evaluate the reversibility of NPAEs via the Patient Health Questionnaire (PHQ-9), the Insomnia Severity Index (ISI), and the Hospital Anxiety and Depression Scale (HADS-A and D) in patients who started antiretroviral therapy with dolutegravir (DTG) or bictegravir (BIC). These patients were switched to DRV/c or DOR. Scales were compared at the moment of the switch and 12 weeks later. Results: We included 1153 treatment-naïve men, 676 (58.7%) with BIC and 477 (41.3%) with DTG. A total of 32 (2.7%) experienced NPAEs that led to discontinuation. Insomnia was found in 20 patients; depression via PHQ-9 in 21 patients, via HADS-D in 5 patients, and anxiety via HADS-A in 12 patients. All of them were evaluated by a psychiatrist at the moment of the symptoms; 7 (21.8%) started psychotropic drugs. After 12 weeks of follow-up, PHQ-9, ISI, HADS-A, and HADS-D decreased, with a p-value ≤ 0.05. Conclusions: NPAEs seem to improve after switching to a DRV/c- or DOR-based regimen after the first 4 and 12 weeks.

Pepsin Inhibitors Prevent Inflammation and Loss of Laryngeal Barrier Function in Mice with Gastroesophageal Reflux.

OBJECTIVE: This study aimed to evaluate the role of pepsin inhibitors in the inflammatory response and their effects on laryngeal mucosal integrity during gastroesophageal reflux (GERD) under in vivo conditions. METHODS: A surgical model of GERD was used, in which mice were treated with pepstatin (0.3 mg/kg) or darunavir (8.6 mg/kg) for 3 days. On the third day after the experimental protocol, the laryngeal samples were collected to assess the severity of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and paracellular epithelial permeability to fluorescein). RESULTS: The surgical GERD model was reproduced. It showed features of inflammation and loss of barrier function in the laryngeal mucosa. Pepstatin and darunavir administration suppressed laryngeal inflammation and preserved laryngeal mucosal integrity. CONCLUSION: Pepsin inhibition by the administration of pepstatin and darunavir improved inflammation and protected the laryngeal mucosa in a mouse experimental model of GERD. LEVEL OF EVIDENCE: NA Laryngoscope, 134:3080-3085, 2024.

Repurposing HIV Protease Inhibitors Atazanavir and Darunavir as Antifungal Treatments against Candida albicans Infections: An In Vitro and In Vivo Study.

Candida albicans is the chief etiological agent of candidiasis, a mycosis prevalent in individuals with acquired immunodeficiency syndrome (AIDS). In recent years, the introduction of human immunodeficiency virus (HIV) protease inhibitors (HIV-PI) has reduced the prevalence of candidiasis in these patients. Seeking new therapeutic strategies based on the perspective of drug repositioning, we evaluated the effects of two second-generation HIV-PIs, atazanavir (ATV) and darunavir (DRV), on virulence factors of C. albicans and experimental candidiasis. For this, clinical strains of C. albicans were subjected to in vitro and in vivo treatments with ATV or DRV. As a result, ATV and DRV exhibited antifungal activity against fungal cells at 512 µg/mL, reduced the viability and biomass of biofilms, and inhibited filamentation of C. albicans. In addition, these HIV-PIs downregulated the expression of SAP2 and BRC1 genes of C. albicans. In an in vivo study, prophylactic use of ATV and DRV prolonged the survival rate of Galleria mellonella larvae infected with C. albicans. Therefore, ATV and DRV showed activity against C. albicans by reducing cell growth, biofilm formation, filamentation, and expression of virulence genes. Furthermore, ATV and DRV decreased experimental candidiasis, suggesting the repurposing of HIV-PIs as antifungal treatments for C. albicans infections.

The effect of protease inhibitor-based dual antiretroviral regimens on CD4/CD8 ratio during the first year of therapy in ART-naïve patients with HIV-infection.

OBJECTIVES: To assess the effect of protease inhibitor (PI)-based dual therapy on CD4/CD8 ratio during the first year of therapy in antiretroviral therapy (ART)-naïve patients using data from randomized controlled clinical trials. METHODS: We pooled data from the GARDEL and ANDES studies, both randomized controlled clinical trials that recruited ART-naïve people living with HIV and randomly assigned them to receive PI-based dual therapy (DT) or triple therapy (TT) aiming to compare viral efficacy. We compared median CD4/CD8 ratios and the proportion of patients with CD4/CD8 ratio > 1 at 48 weeks after ART initiation in both treatment arms using the Mann-Whitney U-test and the χ2 test. We performed subgroup analysis for patients > 50 years old, with baseline CD4 counts ≤ 200 cells/µL, viral load > 100 000 HIV RNA copies/mL, and ritonavir-boosted lopinavir-based therapy. RESULTS: We analysed data from 571 patients: 292 on DT and 279 on TT. No differences were observed in CD4/CD8 ratio (0.632 vs. 0.617, P = 0.729) or in the proportion of patients with CD4/CD8 ratio > 1 (17.9% vs. 19.3%, P = 0.678) 48 weeks after ART initiation. Subgroup analysis showed no further differences. CONCLUSION: The impact of PI-based DT regimens on the CD4/CD8 ratio during the first year of treatment for ART-naïve patients is similar to that of TT.

Efeitos in vitro e in vivo dos inibidores da protease do HIV Atazanavir e Darunavir nos fatores de virulência de Candida albicans: formação de biofilme, filamentação e infecção em modelo de Galleria mellonella / In vitro and in vivo effects of the HIV Protease Inhibitors Atazanavir and Darunavir in virulence factors of Candida albicans: biofilm formation, hyphae formation and infection in Galleria mellonella model

Candida albicans é um fungo que habitualmente coloniza superfícies mucosas de humanos e pode assumir caráter patogênico a depender de fatores do hospedeiro. Portadores da Síndrome da Imunodeficiência Humana, causada pelo Vírus da Imunodeficiência Humana (HIV), são propícios a apresentar candidose nas mucosas devido a imunodeficiência celular que apresentam. A introdução da Terapia Antirretroviral (TARV), em especial o surgimento dos Inibidores da Protease do HIV (IPs-HIV), reduziu drasticamente a incidência e prevalência destas patologias ao longo dos anos. Estudos clínicos e epidemiológicos com IPs-HIV de primeira geração demostraram que tal redução não se deve exclusivamente à melhora imunológica promovida pela TARV, e pesquisas in vitro já demonstraram propriedades antifúngicas e antibiofilme de alguns IPs-HIV de primeiras gerações em C. albicans. Sendo assim, o objetivo deste estudo foi avaliar os efeitos do Atazanavir (ATV) e Darunavir (DRV), dois IPs-HIV de segunda e terceira geração respectivamente em uso clínico atual no Brasil, em diferentes fatores de virulência de C. albicans. Para isso foram realizados estudos com duas cepas clínicas de C. albicans isoladas de lesões de candidose orofaríngea de pacientes portadores de HIV para avaliar a ação in vitro das drogas na morfogênese, formação de biofilme (contagem de células viáveis e quantificação de biomassa) e na expressão dos genes de virulência BRC1 e SAP2, e in vivo no efeito protetor desses medicamentos na infecção experimental por C. albicans em modelo de Galleria mellonella. Os dados foram analisados por teste t, ANOVA, Kruskal-Wallis, Dunn e Kaplan-Meier (p<0,05). A Concentração Inibitória Mínima (CIM) para ambos os IPs-HIV testados foi 512 µg/mL. Nos biofilmes, a redução na contagem de UFC/mL de C. albicans nos grupos tratados com IPs-HIV foi de até 6,81 Log. A biomassa dos biofilmes tratados também sofreu reduções significantes para ATV (82%), DRV (81%) comparada ao grupo controle.DRV e ATV promoveram redução estatisticamente significante de expressão gênica de SAP2 e BRC1, respectivamente, quando comparados ao controle (p<0,05). Em relação à morfogênese de C. albicans, ATV e DRV inibiram significativamente a formação de hifas (p=0,0183). No estudo in vivo, o uso profilático de ATV e DRV em G. mellonella infectadas com C. albicans prolongou em até 40% a sobrevivência das larvas (p=0,0004). Conclui-se que ATV e DRV inibiram a filamentação e apresentaram atividade antifúngica, antibiofilme e na expressão de genes de fatores de virulência de C. albicans e preveniram candidose em G. mellonella(AU)

Candida albicans is a fungus that usually colonizes mucous surfaces of humans and can assume pathogenic character depending on host factors. Patients with Human Immunodeficiency Syndrome, caused by the Human Immunodeficiency Virus (HIV), are favorable to present mucous candidosis due to the cellular immunodeficiency they present. The introduction of Antiretroviral Therapy (ART), especially the emergence of HIV Protease Inhibitors (HIV-PI), has drastically reduced the incidence and prevalence of these mycosis over the years. Clinical and epidemiological studies with firstgeneration HIV-PIs have shown that this reduction is not exclusively due to the immunological improvement promoted by ART, and in vitro research has already demonstrated antifungal and antibiofilm properties of firsts-generations HIV-PIs on C. albicans. Thus, the aim of this study was to evaluate the effects of Atazanavir (ATV) and Darunavir (DRV), two HIV-PIs of second and third generation respectively currently in clinical use in Brazil, on virulence factors of C. albicans. For this purpose, studies were carried out with two clinical strains of C. albicans isolated from lesions of oropharyngeal candidosis of HIV positive patients to evaluate in vitro action of the drugs on morphogenesis, biofilm formation (number of viable cell and biomass determination) and virulence factor genes BRC1 and SAP2 expression and in vivo on the protective effect of these drugs on experimental infection by C. albicans in Galleria mellonella model. Data were analyzed by t Student, ANOVA, Kruskal-Wallis and Dunn and Kaplan-Meier (p<0.05) tests. The Minimum Inhibitory Concentration (MIC) for both tested HIV-PIs was 512 µg/mL. In biofilms, a reduction in the CFU/mL count of C. albicans in the groups treated with HIV-PIs was up to 6.81 log. The biomass of biofilms also suffered significant reductions for ATV (82%) and DRV (81%) compared to the control group. DRV and ATV statistically significantly downregulated the expression of SAP2 and BRC1 genes respectively (p<0,05). Regarding the morphogenesis of C. albicans, ATV and DRV inhibited the formation of hyphae (p = 0.0183). In the in vivo study, the prophylactic use of ATV and DRV in G. mellonella infected with C. albicans prolonged larval survival by up to 40% (p = 0.0004). We can conclude that ATV and DRV inhibited filamentation and showed antifungal activity, being able to inhibit growth, formation and virulence factors gene expression of C. albicans biofilm and prevented candidosis in G. mellonel(AU)

Long-term virological effectiveness with darunavir/ritonavir-based salvage therapy in people living with HIV/AIDS from São Paulo, Brazil.

Even though darunavir/ritonavir (DRV/r) has high potency and a greater genetic barrier, there are few studies on the long-term effectiveness of DRV/r-based salvage therapy in people living with HIV (PLWH) in low and middle-income countries. This retrospective cohort study, from São Paulo, Brazil, included ART-experienced PLWH aged ≥18 years with virological failure (VF) who had started DRV/r plus an optimized background regimen (OBR) between 2008 and 2012. The proportion of patients with viral load (VL) <50 copies/mL, the improved mean CD4+ T cell count and the factors associated with VF during the 144-week follow-up were assessed. The study included 173 patients with the following characteristics [median (interquartile range)]: age 48 (42 -53) years; CD4+ T cell count, 229 (89 -376) cells/mm3; VL, 4.26 (3.70 -4.74) log10; 6 (4 -7) previous regimens; and 100 (38 -156) months of VF. After 144 weeks, 129 (75%) patients had VL< 50 copies/mL and a mean increase in the CD4+ T cell count of 190 cells/mm3. VL>100,000 copies/mL and poor adherence were associated with VF. DRV/r plus an OBR showed high long-term virological suppression and immunological recovery. VL>100,000 copies/mL and poor adherence were associated with VF at 144 weeks.

Darunavir inhibits Cryptococcus neoformans/Cryptococcus gattii species complex growth and increases the susceptibility of biofilms to antifungal drugs.

Introduction. Cryptococcus species are pathogens commonly associated with cases of meningoencephalitis in individuals who are immunosuppressed due to AIDS.Aim. The aim was to evaluate the effects of the antiretroviral darunavir alone or associated with fluconazole, 5-flucytosine and amphotericin B against planktonic cells and biofilms of Cryptococcus species.Methodology. Susceptibility testing of darunavir and the common antifungals against 12 members of the Cryptococcus neoformans/Cryptococcus gattii species complex was evaluated by broth microdilution. The interaction between darunavir and antifungals against planktonic cells was tested by a checkerboard assay. The effects of darunavir against biofilm metabolic activity and biomass were evaluated by the XTT reduction assay and crystal violet staining, respectively.Results. Darunavir combined with amphotericin B showed a synergistic interaction against planktonic cells. No antagonistic interaction was observed between darunavir and the antifungals used. All Cryptococcus species strains were strong biofilm producers. Darunavir alone reduced biofilm metabolic activity and biomass when added during and after biofilm formation (P<0.05). The combination of darunavir with antifungals caused a significant reduction in biofilm metabolic activity and biomass when compared to darunavir alone (P<0.05).Conclusion. Darunavir presents antifungal activity against planktonic cells of Cryptococcus species and synergism with amphotericin B. In addition, darunavir led to reduced biofilm formation and showed activity against mature biofilms of Cryptococcus species. Activity of the antifungals against mature biofilms was enhanced in the presence of darunavir.

Effectiveness and risk factors for virological outcome of darunavir-based therapy for treatment-experienced HIV-infected patients.

OBJECTIVE: We evaluated the effectiveness of darunavir (DRV) treatment plus an optimized background regimen in 120 HIV-1 treatment-experienced patients. DESIGN: Retrospective cohort, multicenter study. METHODS: Adults >16 years with virological treatment failure starting therapy with a DRV-containing regimen were included. Effectiveness was evaluated as the percentage of patients with an undetectable HIV-1 RNA viral load (<50 and <200 copies/mL) after 48 weeks, and changes in CD4+ cell counts. We evaluated the risk factors associated with treatment failure. RESULTS: Of the cohort, 83 % were men with a median age of 45 years (interquartile range, IQR 40-51). They had experienced treatment for a median of 13 years (IQR 9-17) with a median of six previous regimens (IQR 4-7), all using protease inhibitors. After treatment, 82 % (95 % confidence interval, CI 74-88 %) of patients had an HIV-1 RNA viral load <200 copies/mL and 69 % (95 % CI 60-76 %) had <50 copies/mL. The CD4+ cell count increased by 378 cells/µL (IQR 252-559; P < 0.001 vs. baseline). Risk factors associated with poor outcome were age >40 years [odds ratio, OR 0.15 (95 % CI 0.10-0.78); P = 0.015], use of raltegravir in the regimen [OR 0.37 (95 % CI 0.10-0.97); P = 0.046], and baseline CD4+ cell count <200 cells/µL [OR 2.79 (95 % CI 1.11-6.97); P = 0.028]. CONCLUSION: In this Mexican cohort Darunavir was metabolically safe, well tolerated and achieved high rates of virological suppression in highly treatment-experienced patients infected with HIV-1.

A critical review of properties of darunavir and analytical methods for its determination.

Darunavir is a synthetic non-peptidic protease inhibitor that has been shown to be extremely potent against wild-type HIV, and it is an important component of highly active antiretroviral treatment (HAART), which is considered as one of the most significant advances in the field of HIV therapy. However, there are some concerns about darunavir quality control. Darunavir shows pseudo-polymorphism: in different ambient conditions one pseudo-polymorphic form can change to another. This behavior of darunavir is problematic because the dosage form is exposed to different ambient conditions around the world, since HIV/AIDS is prevalent globally. Issues around differences in the solubility and effects that different forms of darunavir can cause are of concern, and a more stable form is preferable. Important investigations of darunavir such as dissolution behavior, polymorphism, stability and degradation studies, and the impact of that on the quality of the product are being conducted by our working group. A cure for HIV/AIDS remains a long-term commitment, and there is much yet to achieve. This article discusses, by a critical review of the literature, the impact of the use of darunavir in the treatment of HIV-infected patients, its physical-chemical properties, the analytical methods to determine it, and challenges that remain in order to ensure the quality and stability of darunavir.

Novel poly(ethylene oxide)-b-poly(propylene oxide) copolymer-glucose conjugate by the microwave-assisted ring opening of a sugar lactone.

In this work, we investigated for the first time the conjugation of gluconolactone to a poly(ethylene oxide)-poly(propylene oxide) block copolymer by a microwave-assisted ring opening reaction. The glucosylated copolymer was obtained with high yield (90%). A conjugation extent of approximately 100% was achieved within 15 min. The modification reduced the critical micellar concentration and increased the size of the micelles. The agglutination of the modified polymeric micelles by a soluble lectin that binds glucose confirmed the recognizability of the modified nanocarrier. Finally, the solubilization of darunavir, an anti-HIV protease inhibitor, showed a sharp increase of the aqueous solubility from 91 microgram/mL to 14.2 and 18.9 mg/mL for 10% w/v pristine and glucosylated polymeric micelles, respectively.

Total and unbound darunavir pharmacokinetics in pregnant women infected with HIV-1: results of a study of darunavir/ritonavir 600/100 mg administered twice daily.

OBJECTIVES: Antiretroviral therapy during pregnancy is recommended to reduce the risk of mother-to-child transmission of HIV and for maternal care management. Physiological changes during pregnancy can affect pharmacokinetics, potentially altering pharmacological activity. We therefore evaluated the pharmacokinetics of twice-daily (bid) darunavir in HIV-1-infected pregnant women. METHODS: HIV-1-infected pregnant women receiving an antiretroviral regimen containing darunavir/ritonavir 600/100 mg bid were enrolled in this study. Total and unbound darunavir and total ritonavir plasma concentrations were obtained over 12 h during the second and third trimesters and postpartum. Total darunavir and ritonavir plasma concentrations were determined using a validated high-performance liquid chromatography tandem mass spectrometry assay and unbound darunavir was determined using (14) C-darunavir-fortified plasma. Pharmacokinetic parameters were derived using noncompartmental analysis. RESULTS: Data were available for 14 women. The area under the plasma concentration-time curve from 0 to 12 h (AUC12h) for total darunavir was 17-24% lower during pregnancy than postpartum. The AUC12h for unbound darunavir was minimally reduced during pregnancy vs. postpartum. The minimum plasma concentration (Cmin) of total and unbound darunavir was on average 43-86% and 10-14% higher, respectively, during pregnancy vs. postpartum. The antiviral response (< 50 HIV-1 RNA copies/mL) was 33% at baseline and increased to 73-90% during treatment; the percentage CD4 count increased over time. One serious adverse event was reported (increased transaminase). All 12 infants born to women remaining in the study at delivery were HIV-1-negative; four of these infants were premature. CONCLUSIONS: Total darunavir exposure decreased during pregnancy. No clinically relevant change in unbound (active) darunavir occurred during pregnancy, suggesting that no dose adjustment is required for darunavir/ritonavir 600/100 mg bid in pregnant women.

Virologic and immunologic effectiveness at 48 weeks of darunavir-ritonavir-based regimens in treatment-experienced persons living with HIV-1 infection in clinical practice: a multicenter Brazilian cohort.

INTRODUCTION: Published data addressing the effectiveness of darunavir-ritonavir (DRV/r)-based therapy for multiexperienced patients in developing countries are scarce. This study evaluated the 48-week virologic and immunologic effectiveness of salvage therapy based on DRV/r for the treatment of multidrug-experienced HIV-1-infected adults in Brazil. MATERIALS AND METHODS: A multicenter retrospective cohort study was carried out with multidrug-experienced adults who were on a failing antiretroviral therapy and started a DRV/r-based salvage therapy between 2008 and 2010. The primary effectiveness end point was the proportion of patients with virologic success (plasma HIV-1 RNA <50 copies/mL at week 48). RESULTS: At 48 weeks, 73% of the patients had HIV-RNA <50 copies/mL and a mean increase of 108 CD4 cells/mm(3). Higher baseline viral load, lower baseline CD4 count, younger age, and 3 or more DRV/r-associated resistance mutations were significantly predictive of virologic failure. Concomitant use of raltegravir was strongly associated with virologic success. CONCLUSION: The use of DRV/r-based regimens for salvage therapy is an effective strategy in the clinical care setting of a developing country.

Desenvolvimento de métodos analíticos qualitativos para a análise de darunavir comprimidos / Development of qualitative analytical methods for monitoring darunavir tablets

O darunavir é um inibidor de protease utilizado para o tratamento da infecção pelo HIV. Trata-se de um dos pilares da terapia de coquetel para pacientes portadores do vírus. O controle de qualidade na indústria farmacêutica, para identificação do teor de substância ativa e estudo das características físico-químicas do fármaco, é de fundamental importância para garantir a qualidade do produto final. O darunavir, até então, não possui métodos de análise padronizados em compêndios oficiais. Este fato justifica novas pesquisas nesta área para o desenvolvimento e validação de métodos analíticos, bem como a análise químico-farmacêutica para este fármaco tanto na matéria-prima como no produto acabado. Dessa forma, neste trabalho foram realizados (a) peso médio; (b) determinação do ponto de fusão; (c) cromatografia em camada delgada; (d) análise na região do ultravioleta; (e) análise na região do infravermelho e (f) cromatografia líquida de alta eficiência. Através do desenvolvimento das técnicas propostas é possível avaliar qualitativamente a qualidade de darunavir em comprimidos.

Darunavir is a protease inhibitor used in the treatment of HIV infection. It is a pillar of the drug cocktail for patients diagnosed with the virus. Quality control in the pharmaceutical industry, to verify the content of active substance and study the physicochemical characteristics of the drug, is essential to ensure final product quality. Until now, standardized methods for the analysis of darunavir have not been available in official compendia. This justifies new research, to develop and validate analytical methods, as well as physicochemical and pharmaceutical analysis for this drug, both as a raw material and a finished product. Thus, in this study, (a) the average weight of darunavir tablets and (b) the melting point of the pure drug were determined, and the following analytical techniques were performed: (c) thin-layer chromatography, (d) ultraviolet spectroscopy, (e) infrared spectroscopy and (f) high performance liquid chromatography. By developing the above techniques, it is possible to make a qualitative assessment of the quality of darunavir tablets.

Effects of once-daily darunavir/ritonavir versus lopinavir/ritonavir on metabolic parameters in treatment-naive HIV-1-infected patients at week 96: ARTEMIS.

In the ARTEMIS trial, 689 treatment-naïve, HIV-1-infected adults received darunavir/ritonavir (DRV/r) 800/100 mg every day or lopinavir/ritonavir (LPV/r) 800/200 mg total daily dose plus fixed-dose tenofovir/emtricitabine. Week 96 metabolic parameters are reported. Adverse events (AEs) classed as metabolism/nutrition disorders were observed in 14% of DRV/r and 22% of LPV/r patients. Lipid-related AEs were reported in fewer DRV/r (8%) than LPV/r (16%) patients. A small increase in glucose and insulin levels was observed at week 96 in both groups. Lipoma was the only lipodystrophy-related AE reported in >1% of patients (DRV/r, n = 1; LPV/r, n = 4) and no grade 3 or 4 lipodystrophy-related AEs were reported. No clinically relevant changes from baseline were seen in anthropometric measurements in either group. Median mid-waist/hip ratio at week 96 was comparable to baseline in both arms. Over 96 weeks, DRV/r had a similar effect on glucose and insulin levels but a more favourable lipid profile than LPV/r in treatment-naïve, HIV-infected patients.

High rate of virologic suppression with darunavir/ritonavir plus optimized background therapy among highly antiretroviral-experienced HIV-infected patients: results of a prospective cohort study in São Paulo, Brazil

OBJECTIVES: To assess the virologic and immunological response of darunavir/ritonavir plus optimized background therapy in highly antiretroviral-experienced HIV-infected patients in Brazil. METHODS: Prospective cohort study carried out in a tertiary center in Sao Paulo, Brazil. Three-class antiretroviral-experienced patients with confirmed virologic failure began darunavir/ritonavir plus optimized background therapy (nucleoside/tide reverse transcriptase inhibitors ± raltegravir ± enfuvirtide ± maraviroc) after performing a genotypic resistance assay. Clinical evaluation and laboratory tests were collected at baseline and at weeks 12, 24, and 48. Multivariate analysis was performed to identify predictors of virologic response at 48 weeks. RESULTS: Ninety-two patients were included. The median of darunavir resistant mutation was 1 (range 0-6). The median genotypic sensitivity score in the optimized background therapy was 2 (interquartile range 1-2). At week 48, 83% (95% CI: 75-90%) had an HIV RNA level <50 copies/mL and the median CD4 cell count was 301 (interquartile range 224-445) cells/mm³. Baseline HIV RNA >100 000 copies/mL was inversely associated with virologic success at week 48 (HR: 0.22, 95% CI: 0.06-0.85, p = 0.028). CONCLUSIONS: Darunavir/ritonavir plus optimized background therapy was a highly effective salvage regimen under clinical routine conditions in a referral center in Brazil, which is similar to the reported in high-income countries.