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.

Bioinformatic analysis of post-transmission viral readaptation in Argentine patients with acute HIV-1 infection

During the acute phase of HIV-1 infection, a strong readaptation occurs in the viral population. Our objective was to analyze the post-transmission mutations associated with escape to the cytotoxic immune response and its relationship with the progression of the infection. In this study, a total of 17 patients were enrolled during acute/early primary HIV infection and 8 subjects that were the HIV positive partner resulting in 8 transmission pairs. Genotyping of the genetic polymorphisms of HLA class I A and B was performed using PCR-SSOP. Viral RNA extraction was from plasma. 570 single Gag-gene amplifications were obtained by limiting-dilution RT-PCR. Epitope prediction was performed with NetMHC CBS prediction server for the 19 HLA-A and B alleles. Cytotoxic response prediction was performed by using the IEDB Analysis Resource. From our results, we deduce that the transmitted CTL / gag escape frequency in the founder virus was at least double compared to the post-transmission events. Additionally, by means of an algorithm that combines these frequencies, we observed that the founder viruses better adapted to the HLA A / B alleles of the recipient could contribute to a greater progression of the infection. Our results suggest that there is a large adaptation of HIV-1 to the HLA A / B alleles prevalent in our population. However, despite this adaptive advantage, the virus needs to make "readjustments" through new escape and compensatory mutations. Interestingly, according to our results, this readaptation could have a role in the progression of the infection.

Etravirine in treatment-experienced, HIV-1-infected children and adolescents: 48-week safety, efficacy and resistance analysis of the phase II PIANO study

OBJECTIVES

PIANO (Paediatric study of Intelence As an NNRTI Option; TMC125-C213; NCT00665847) assessed the safety/tolerability, antiviral activity and pharmacokinetics of etravirine plus an optimized background regimen (OBR) in treatment-experienced, HIV-1-infected children (≥ 6 to < 12 years) and adolescents (≥ 12 to < 18 years) over 48 weeks.

METHODS

In a phase II, open-label, single-arm study, 101 treatment-experienced patients (41 children; 60 adolescents) with screening viral load (VL) ≥ 500 HIV-1 RNA copies/mL received etravirine 5.2 mg/kg (maximum dose 200 mg) twice a day (bid) plus OBR.

RESULTS

Sixty-seven per cent of patients had previously used efavirenz or nevirapine. At week 48, the most common treatment-related grade ≥ 2 adverse event (AE) was rash (13%); 12% experienced grade 3 AEs. Only two grade 4 AEs occurred (both thrombocytopaenia, not etravirine related). At week 48, 56% of patients (68% children; 48% adolescents) achieved a virological response (VL<50 copies/mL; intent-to-treat, noncompleter=failure). Factors predictive of response were adherence > 95%, male sex, low baseline etravirine weighted genotypic score and high etravirine trough concentration (C0h ). Seventy-six patients (75%) completed the trial; most discontinuations occurred because of protocol noncompliance or AEs (8% each). Sixty-five per cent of patients were > 95% adherent by questionnaire and 39% by pill count. Forty-one patients experienced virological failure (VF; time-to-loss-of-virological-response non-VF-censored algorithm) (29 nonresponders; 12 rebounders). Of 30 patients with VF with paired baseline/endpoint genotypes, 18 (60%) developed nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations, most commonly Y181C. Mean etravirine area under the plasma concentration-time curve over 12 h (AUC0-12h ; 5216 ng h/mL) and C0h (346 ng/mL) were comparable to adult target values.

CONCLUSIONS

Results with etravirine 5.2 mg/kg bid (with OBR) in this treatment-experienced paediatric population and etravirine 200 mg bid in treatment-experienced adults were comparable. Etravirine is an NNRTI option for treatment-experienced paediatric patients.

Virological response with fully active etravirine: pooled results from the DUET-1 and DUET-2 trials

The objective of this subanalysis of the Phase III DUET trials was to examine virological response to an etravirine-containing regimen in patients harbouring virus fully sensitive to etravirine. Full etravirine sensitivity was defined as fold change in 50% effective concentration (FC) ≤3 or weighted genotypic score ≤2. At Week 48 in the etravirine group, 74% of patients with etravirine FC ≤3 and 77% with etravirine genotypic score ≤2 had viral load <50 HIV-1 RNA copies/mL, versus 48% and 46%, respectively, in the placebo group (P < 0.0001). Response rates increased with baseline phenotypic sensitivity score, but were consistently higher with etravirine (56-82%) than placebo (2-72%). Similar observations were made in patients harbouring virus with full etravirine and darunavir sensitivity. Our findings support current recommendations to include three active agents in treatment-experienced patients' regimens.

HCV RNA decline in the first 24 h exhibits high negative predictive value of sustained virologic response in HIV/HCV genotype 1 co-infected patients treated with peginterferon and ribavirin

BACKGROUND

Treatment with Peg-interferon and ribavirin (PEG-IFN/RBV) for HIV patients co-infected with hepatitis C virus (HCV) genotype 1 has suboptimal rates of response. Viral kinetics has emerged as one of the best prognostic factors of treatment outcome.

METHODS

Twenty HIV/HCV genotype 1 co-infected patients in treatment with PEG-IFN/RBV, had blood drawn at baseline, 24 h, 4, 12, 24, 48, and 72 weeks. HCV-RNA levels were evaluated at each time point. ROC curves were used to evaluate the log10 HCV-RNA decay at 24 h that exhibits the best predictive value of achieving response. Genomic characterization of HCV NS5A at both interferon sensitivity-determining region (ISDR) and protein-kinase binding (PKRBD) domains were performed in order to evaluate its heterogeneity and association with 24 h HCV-RNA decay and SVR.

RESULTS

Non-responder patients exhibited a mean of 0.7 log10 (SD 0.74 log10) HCV-RNA decay at 24 h, whereas responder-patients presented 1.6 log10 (SD 0.28 log10), p = 0.04. A reduction in HCV viral load from baseline to 24 h of < 1.4 had a negative predictive value for achieving SVR of 100% and a positive predictive value of 50%. HCV genotype 1 isolates from patients with a decrease of HCV-RNA at 24 h > 1.4 log10, exhibited 3.1(SD 1.5) amino acids substitutions in ISDR and 4.8(SD 2.3) in PKRBD regions and 1.6(SD 0.7) and 2.4(SD 1.3), respectively, in those patients presenting lower reduction in HCV-RNA.

CONCLUSIONS

HIV/HCV genotype 1 co-infected patients with a decrease in HCV-VL at 24 h > 1.4 log10 are more likely to achieve SVR when treated with PEG-IFN/RBV than those with lower levels of HCV-RNA decay. Along with other host-related and viral-related prognostic factors in HIV/HCV co-infected patients, this very early time point of evaluation could be of relevance in the management of HCV-specific treatment.

Prioritising prevention strategies for patients in antiretroviral treatment programmes in resource-limited settings

Expanded access to antiretroviral therapy (ART) offers opportunities to strengthen HIV prevention in resource-limited settings. We invited 27 ART programmes from urban settings in Africa, Asia and South America to participate in a survey, with the aim to examine what preventive services had been integrated in ART programmes. Twenty-two programmes participated; eight (36%) from South Africa, two from Brazil, two from Zambia and one each from Argentina, India, Thailand, Botswana, Ivory Coast, Malawi, Morocco, Uganda and Zimbabwe and one occupational programme of a brewery company included five countries (Nigeria, Republic of Congo, Democratic Republic of Congo, Rwanda and Burundi). Twenty-one sites (96%) provided health education and social support, and 18 (82%) provided HIV testing and counselling. All sites encouraged disclosure of HIV infection to spouses and partners, but only 11 (50%) had a protocol for partner notification. Twenty-one sites (96%) supplied male condoms, seven (32%) female condoms and 20 (91%) provided prophylactic ART for the prevention of mother-to child transmission. Seven sites (33%) regularly screened for sexually transmitted infections (STI). Twelve sites (55%) were involved in activities aimed at women or adolescents, and 10 sites (46%) in activities aimed at serodiscordant couples. Stigma and discrimination, gender roles and funding constraints were perceived as the main obstacles to effective prevention in ART programmes. We conclude that preventive services in ART programmes in lower income countries focus on health education and the provision of social support and male condoms. Strategies that might be equally or more important in this setting, including partner notification, prompt diagnosis and treatment of STI and reduction of stigma in the community, have not been implemented widely.

Antiviral activity of apricitabine in treatment-experienced HIV-1-infected patients with M184V who are failing combination therapy

OBJECTIVES

Apricitabine (ATC) is a novel deoxycytidine analogue nucleoside reverse transcriptase inhibitor (NRTI) with significant antiviral activity in vitro, including activity against HIV-1 with reverse transcriptase mutations that confer resistance to other NRTIs. ATC has shown promising antiviral activity and good tolerability when given as monotherapy for 10 days in treatment-naïve HIV-1-infected patients.

METHODS

In this Phase II randomized, double-blind study, 51 treatment-experienced HIV-1-infected patients with the reverse transcriptase mutation M184V who were failing therapy which included lamivudine (3TC) were randomized to receive twice-daily 600 mg ATC, 800 mg ATC or 150 mg 3TC for 21 days. Patients remained on their existing background regimen until day 21, when background therapy could be optimized according to genotype at screening.

RESULTS

At day 21, the mean change in viral load was -0.71 and -0.90 log(10) HIV-1 RNA copies/mL in the 600 and 800 mg ATC groups, respectively, compared with a -0.03 log(10) change in the 3TC group. In patients with at least three thymidine analogue mutations (TAMs) at baseline, greater reductions in viral load were observed in the 800 mg ATC group at day 21 than in the 600 mg ATC group. Few genotypic changes were detected at day 21 [two patients (600 mg ATC) lost and three patients (800 mg ATC) gained a TAM] and all patients with detectable virus retained the M184V mutation. The safety profiles of the two ATC doses were similar to that of 3TC.

CONCLUSIONS

Over the 21-day treatment period, ATC showed promising antiviral activity and was well tolerated in treatment-experienced patients with M184V, with or without additional TAMs.

Metabolic profile and cardiovascular risk factors among Latin American HIV-infected patients receiving HAART

OBJECTIVE

Determine the prevalence of metabolic abnormalities (MA) and estimate the 10-year risk for cardiovascular disease (CVD) among Latin American HIV-infected patients receiving highly active anti-retroviral therapy (HAART).

METHODS

A cohort study to evaluate MA and treatment practices to reduce CVD has been conducted in seven Latin American countries. Adult HIV-infected patients with at least one month of HAART were enrolled. Baseline data are presented in this analysis.

RESULTS

A total of 4,010 patients were enrolled. Mean age (SD) was 41.9 (10) years; median duration of HAART was 35 (IQR: 10-51) months, 44% received protease inhibitors. The prevalence of dyslipidemia and metabolic syndrome was 80.2% and 20.2%, respectively. The overall 10-year risk of CVD, as measured by the Framingham risk score (FRF), was 10.4 (24.7). Longer exposure to HAART was documented in patients with dyslipidemia, metabolic syndrome and type 2 diabetes mellitus. The FRF score increased with duration of HAART. Male patients had more dyslipidemia, high blood pressure, smoking habit and higher 10-year CVD than females.

CONCLUSIONS

Traditional risk factors for CVD are prevalent in this setting leading to intermediate 10-year risk of CVD. Modification of these risk factors through education and intervention programs are needed to reduce CVD.

Use of darunavir and enfuvirtide in a pregnant woman

A 41-year-old pregnant woman with multiple virological failures started darunavir, enfuvirtide, zidovudine and lamivudine at week 28 of pregnancy. During week 38, the patient had a viral load <400 copies/mL and a CD4 count of 180 cells/mm3 (13%). The child was found to be in good health, with negative HIV-polymerase chain reactions at birth, at two and at six months.

HCV genotype distribution among HIV co-infected individuals in Argentina: relationship with host and viral factors

Coinfection with hepatitis C virus (HCV) in individuals infected with HIV is associated with a higher incidence of liver injury hepatic decompensation, and decreased survival than that observed in an HIV-monoinfected population. While prevalence studies on HIV/HCV coinfection have been performed in the U.S. and in some European countries, little is known about HCV genotype distribution in Latin America. The main objective was to evaluate the HCV prevalence and genotypes among HIV co-infected patients, and their relationship with HCV viral load, serum ALT level and T lymphocyte CD4+ cell count. These data pursue to increase the knowledge from South America about a pressing problem from HIV-infected patients. Retrospectively collected specimens from 593 HIV-positive individuals in Argentina were tested for anti-HCV These were analyzed for HCV-RNA qualitatively and quantitatively. The HCV genotype was determined by the RFLP method. One hundred and twenty-nine (21.7%) HIV-infected individuals were anti-HCV positive; 65.9% of them exhibited detectable HCV-RNA. Genotype 1 (43, la/c; 9, 1b; and 5, 1a/c+1b) was present in 57, while 1, 14 and 13 were infected with genotype 2, 3 or a mix, respectively. Co-infected individuals were more likely to be male, without significant differences in age and CD4+ cell counts than HIV-monoinfected individuals. HCV infection prevalence in patients co-infected with HIV highlights the impending public health impact of this problem. Considering the increasing rate of HCV genotypes with lower response rates to treatment among HIV co-infected patients, antiretroviral therapy success might be jeopardized by HCV coinfection.

Hepatitis B virus genotype distribution and its lamivudine-resistant mutants in HIV-coinfected patients with chronic and occult hepatitis B

Hepatitis B virus (HBV) genotypes were examined in HIV-infected patients with chronic and occult HBV infection. From a total population of 593 HIV-infected patients, 22 individuals (prevalence 3.7%) were found to be HBsAg while 72 (12.1%) were found to be anti-HBc alone. From them, 20 and 4 were HBV DNA positive, respectively. These last four patients are therefore considered to be HBV infected in an occult form. The genotypes could be determined in all 24 HBV-infected patients. HBV-A was the most common (20/24; 83.3%), followed by HBV-D (2/24; 8.3%) and HBV-F (1/24; 4.2%). The remaining sample exhibited mixed infection involving genotypes A and D as pure ones, thus also forming part of three intergenotypic recombinant forms exhibiting different mosaic S gene patterns. The sexual route of transmission was predominant among HBV genotype A-infected patients. Among the 24 HBV DNA-positive patients, point mutations related to lamivudine resistance were found in four strains. These viral strains showed a methionine-to-valine substitution at codon 204 (rtM204V) in association with an upstream B-domain change at rtL180M. Additionally, two of them exhibited the additional rtV173L mutation. The value of HBV molecular monitoring including both HBV viral genomic characterization and genotypic resistance profile in HIV-HBV-coinfected individuals is discussed.

Bayesian network analysis of resistance pathways against HIV-1 protease inhibitors

Interpretation of Human Immunodeficiency Virus 1 (HIV-1) genotypic drug resistance is still a major challenge in the follow-up of antiviral therapy in infected patients. Because of the high degree of HIV-1 natural variation, complex interactions and stochastic behaviour of evolution, the role of resistance mutations is in many cases not well understood. Using Bayesian network learning of HIV-1 sequence data from diverse subtypes (A, B, C, F and G), we could determine the specific role of many resistance mutations against the protease inhibitors (PIs) nelfinavir (NFV), indinavir (IDV), and saquinavir (SQV). Such networks visualize relationships between treatment, selection of resistance mutations and presence of polymorphisms in a graphical way. The analysis identified 30N, 88S, and 90M for nelfinavir, 90M for saquinavir, and 82A/T and 46I/L for indinavir as most probable major resistance mutations. Moreover we found striking similarities for the role of many mutations against all of these drugs. For example, for all three inhibitors, we found that the novel mutation 89I was minor and associated with mutations at positions 90 and 71. Bayesian network learning provides an autonomous method to gain insight in the role of resistance mutations and the influence of HIV-1 natural variation. We successfully applied the method to three protease inhibitors. The analysis shows differences with current knowledge especially concerning resistance development in several non-B subtypes.

A Randomized Trial to Evaluate Lopinavir/Ritonavir versus Saquinavir/Ritonavir in HIV-1-Infected Patients: The Maxcmin2 Trial

Objective

To assess the rate of protocol-defined treatment failure and safety of lopinavir/ritonavir (LPV/r) and saquinavir/ritonavir (SAQ/r).

Design

Open-label, prospective, randomized (1:1), international multi-centre trial.

Methods

Adult HIV-1-infected patients were assigned LPV/r 400/100 mg twice daily or SAQ/r 1000/100 mg twice daily with two or more nucleoside reverse transcriptase inhibitors (NRTIs)/non-NRTIs. All patients, whether on or off the assigned treatment, were followed for 48 weeks.

Results

Of 339 randomized patients, 324 initiated assigned treatment (intention-to-treat/exposed [ITT/e] population). At 48 weeks, treatment failure occurred in 29/163 (18%) and 53/161 (33%) of patients in the LPV/r and SAQ/r arms, respectively (ITT/e, P=0.002, log rank test). In an analysis that also considered those patients who discontinued treatment as having failed treatment (ITT/e/discontinuation=failure), 40/161 (25%) LPV/r-treated individuals versus 63/161 (39%) SAQ/R-treated individuals failed treatment ( P=0.005, log rank test). Discontinuation of the assigned treatment occurred in 23/163 (14%) patients in the LPV/r-treated group, compared with 48/161 (30%) in the SAQ/r-treated group (ITT/e; P=0.001). The primary reasons for premature discontinuation were non-fatal adverse events (LPV/r: 12/163; SAQ/r: 21/161) and patients’ choice (LPV/r: 7/163; SAQ/r: 8/161). In the on-treatment analysis of time to treatment failure, no difference was observed between the two arms ( P=0.27, log rank test).

Conclusion

LPV/r had better antiretroviral effects compared with SAQ/r at the doses and in the formulations studied. This may have been a result of patients’ preferences and ability to adhere to assigned therapy, rather than a result of differences in the intrinsic potency of the study protease inhibitors.

Abacavir compared to protease inhibitors as part of HAART regimens for treatment of HIV infection: patient satisfaction and implications for adherence

The purpose of this study was to compare treatment satisfaction with triple nucleoside reverse transcriptase inhibitor (NRTI) highly active antiretroviral treatment (HAART) regimens including abacavir (ABC) to HAART regimens that include protease inhibitors (PIs) and to estimate the relationship between patient satisfaction and adherence to HAART. Three open-label clinical trials comparing ABC-including HAART regimens with PI-including HAART regimens were completed, two with patients previously untreated with antiretroviral therapy and one with patients successfully treated with PI-including HAART regimens. The HIV Treatment Satisfaction Questionnaire (HIVTSQ) was completed at several time points during each trial. Levels of patient satisfaction with the ABC and PI regimens were compared for all three trials. The correlation between adherence and patient satisfaction scores was measured using data from an adherence questionnaire in one of the studies. In all three clinical trials, patient satisfaction scores were significantly higher with an ABC-including triple NRTI HAART regimen than with a PI-including HAART regimen. The difference was apparent by week 4 of the trial and was maintained throughout the trial time period. Inspection of the item responses in the patient satisfaction questionnaire indicated that treatment convenience, flexibility, impact on lifestyle, and side effects were key factors in the difference in satisfaction between the treatment groups. In addition, patient satisfaction was shown to be significantly correlated with adherence defined as taking 95% or more of prescribed doses. Greater satisfaction was reported by patients given an ABC-including HAART regimen than those given a PI-including HAART regimen. Patient satisfaction may be an indicator for better treatment adherence.

Health-Related Quality of Life in HIV Patients Switching to Twice-Daily Indinavir/Ritonavir Regimen or Continuing with Three-Times-Daily Indinavir-Based Therapy

Objective

To evaluate health-related quality of life (HRQoL) changes in patients treated with indinavir three-times daily after switching to a twice-daily indinavir/ritonavir regimen or continuing with the same regimen.

Methods

Patients on HAART including indinavir three-times-daily with undetectable viral load were randomly assigned to continue with this therapy or to change to a twice-daily indinavir/ritonavir (800/100 mg) regimen. The Medical Outcomes Study HIV Health Survey (MOS-HIV) questionnaire was used as the HRQoL measure.

Results

A total of 118 patients participated in the study, of which 59 (50%) were randomly assigned to continue with the three-times-daily regimen. Patients had a mean age of 39 years and 80% of them were male. At baseline, subjects included in the three-times-daily group presented a significantly greater number of symptoms than subjects in the twice-daily group, but no statistically significant differences were observed in MOS-HIV scores between the groups. In the intention-to-treat (ITT) analysis, a reduction in HRQoL scores was observed in both groups, which was greater in the twice-daily group. In the per protocol analysis, reduction of HRQoL was minimal.

Conclusions

A HRQoL deterioration, greater in the twice-daily group, was observed in this study in the ITT analysis, while HRQoL remained stable in both groups in patients who continued with and tolerated the allocated regimen.

Comparison of first-line antiretroviral therapy with regimens including nevirapine, efavirenz, or both drugs, plus stavudine and lamivudine: a randomised open-label trial, the 2NN Study

BACKGROUND

The 2NN Study was a randomised comparison of the non-nucleoside reverse-transcriptase inhibitors (NNRTI) nevirapine and efavirenz.

METHODS

In this multicentre, open-label, randomised trial, 1216 antiretroviral-therapy-naive patients were assigned nevirapine 400 mg once daily, nevirapine 200 mg twice daily, efavirenz 600 mg once daily, or nevirapine (400 mg) and efavirenz (800 mg) once daily, plus stavudine and lamivudine, for 48 weeks. The primary endpoint was the proportion of patients with treatment failure (less than 1 log(10) decline in plasma HIV-1 RNA in the first 12 weeks or two consecutive measurements of more than 50 copies per mL from week 24 onwards, disease progression [new Centers for Disease Control and Prevention grade C event or death], or change of allocated treatment). Analyses were by intention to treat.

FINDINGS

Treatment failure occurred in 96 (43.6%) of 220 patients assigned nevirapine once daily, 169 (43.7%) of 387 assigned nevirapine twice daily, 151 (37.8%) of 400 assigned efavirenz, and 111 (53.1%) of 209 assigned nevirapine plus efavirenz. The difference between nevirapine twice daily and efavirenz was 5.9% (95% CI -0.9 to 12.8). There were no significant differences among the study groups in the proportions with plasma HIV-1 RNA concentrations below 50 copies per mL at week 48 (p=0.193) or the increases in CD4-positive cells (p=0.800). Nevirapine plus efavirenz was associated with the highest frequency of clinical adverse events, and nevirapine once daily with significantly more hepatobiliary laboratory toxicities than efavirenz. Of 25 observed deaths, two were attributed to nevirapine.

INTERPRETATION

Antiretroviral therapy with nevirapine or efavirenz showed similar efficacy, so triple-drug regimens with either NNRTI are valid for first-line treatment. There are, however, differences in safety profiles. Combination of nevirapine and efavirenz did not improve efficacy but caused more adverse events.

Discrepant results in the interpretation of HIV-1 drug-resistance genotypic data among widely used algorithms

OBJECTIVES

The aim of this study was to assess the concordance on the interpretation of HIV-1 drug-resistance genotypic data by three widely used algorithms: Stanford University Database (SU), TruGene (Visible Genetics, Canada) (VG) and VirtualPhenotype (Virco, Belgium) (VP).

METHODS

Genotypic data from 293 HIV-1-infected individuals with treatment failure was interpreted for 14 antiretroviral drugs by the three algorithms.

RESULTS

Complete concordant results among the three systems for all the drugs studied were found in 40/293 (13.7%) samples. Low concordance in the interpretation was observed for most nucleoside reverse transcriptase inhibitors (NRTIs), while results agreed highly for all nonnucleoside reverse transcriptase inhibitors (NNRTIs) and most protease inhibitors (PIs). In pair-wise comparisons, discordant interpretations between SU and VP were found in over 50% of the samples for didanosine, zalcitabine, stavudine and abacavir, and the level of disagreement between VG and VP exceeded 40% for the same drugs. Major discrepancies (high-level resistance interpretation by one algorithm with sensitive interpretation by another) were observed between VG and VP in over 10% of the cases for didanosine, zalcitabine, stavudine and abacavir. On the other hand, the three algorithms had concordant results for lamivudine in over 90% of the cases.

CONCLUSIONS

This work demonstrates the great level of discordance in the interpretation of genotyping results among algorithms, clearly showing the necessity for clinical validation. Moreover, these results suggest that a joint effort from the scientific community as well as national and international HIV societies is needed to achieve a consensus for the interpretation of genotypic data.

[From the HIV body to the ARV body]

The current HIV subjectivity lies on two great enunciative categories: HIV body, raised from Aids epidemic former stage, catheterized by being the viral genius development place. This omnipotent structure appears untouched of medical interdiction. And the ARV body, identified to H.A.A.R.T regime drugs adherence, and to horizontal and vertical machinic flows as well. These categories obtained from Flix Guattari's thoughts, are placed like theoretical framework for predicting of adherence achievement.

Resistance profiles to antiretroviral drugs in HIV-1 drug-naive patients in Argentina

The drug resistance profile of treatment-naive HIV-infected individuals living in Buenos Aires, Argentina, was studied. Samples taken from 94 drug-naive individuals with established HIV infection and 13 patients with primary HIV infection were assessed by nucleotide sequencing and LIPA. The prevalence of drug-associated primary mutations in individuals with established infection was very low. In the viral protease region, 1/86 (1.2%) individuals carried the D30N mutation, whereas 1/85 (1.2%) had the M41L mutation in the reverse transcriptase (RT) region. Secondary mutations in both the protease and RT regions were found in almost 90% of the individuals. In individuals with primary infection, primary mutations were detected in 2/13 (15.4%) patients, one of them carrying M461 mutation in the protease while the other patient had a mutation at codon 184 of the RT. In accordance with current drug resistance testing guidelines, the results of this study suggest that susceptibility tests need not be performed at this time prior to initiation of antiretroviral therapy in HIV-1-infected people in Argentina. However, the public health implications of this subject warrant follow-up studies that will examine a larger number of drug-naive patients, not only in Buenos Aires but also in other major Argentinian cities and in rural areas.

A randomized, double-blind trial comparing azithromycin and clarithromycin in the treatment of disseminated Mycobacterium avium infection in patients with human immunodeficiency virus

Two hundred and forty-six patients infected with human immunodeficiency virus (HIV) who also had disseminated Mycobacterium avium complex received either azithromycin 250 mg every day, azithromycin 600 mg every day, or clarithromycin 500 mg twice a day, each combined with ethambutol, for 24 weeks. Samples drawn from patients were cultured and clinically assessed every 3 weeks up to week 12, then monthly thereafter through week 24 of double-blind therapy and every 3 months while on open-label therapy through the conclusion of the trial. The azithromycin 250 mg arm of the study was dropped after an interim analysis showed a lower rate of clearance of bacteremia. At 24 weeks of therapy, the likelihood of patients' developing 2 consecutive negative cultures (46% vs. 56%, P=.24) or 1 negative culture (59% vs. 61%, P=.80) was similar for azithromycin 600 mg (n=68) and clarithromycin (n=57), respectively. The likelihood of relapse was 39% versus 27% (P=.21) on azithromycin compared with clarithromycin, respectively. Of the 6 patients who experienced relapse, none of those randomized to receive azithromycin developed isolates resistant to macrolides, compared with 2 of 3 patients randomized to receive clarithromycin [corrected]. Mortality was similar in patients comprising each arm of the study (69% vs. 63%; hazard, 95.1% confidence interval, 1.1 [0.7, 1.7]). Azithromycin 600 mg, when given in combination with ethambutol, is an effective agent for the treatment of disseminated M. avium disease in patients infected with HIV.

Comparative studies of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine

OBJECTIVES

To compare the efficacy and safety of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine.

DESIGN

Two multicenter, open-label, randomized 24-week studies.

METHODS

Adults HIV-1 infection, HIV-1 RNA greater than 10000 copies/ml, and no prior lamivudine or protease inhibitor therapy were eligible. In a pilot study (Study A), patients received indinavir at 800 mg every 8 h, 1000 mg every 12 h, or 1200 mg every 12 h. In a subsequent study (Study B), patients received indinavir at 800 mg every 8 h or 1200 mg every 12 h. All subjects received zidovudine (300 mg) and lamivudine (150 mg) every 12 h. An intent-to-treat analysis was used.

RESULTS

In Study A, which enrolled 88 patients, neither HIV-1 RNA nor CD4 cell responses differed significantly between treatment groups at 24 weeks when corrected for multiple comparisons. Study B enrolled 433 patients, but was prematurely discontinued when interim analysis suggested greater efficacy of three-times-daily indinavir. Of the first 87 patients reaching week 24, HIV-1 RNA was less than 400 copies/ml in 91% receiving three-times-daily versus 64% receiving two-times-daily indinavir (P < 0.01).

CONCLUSION

Three-times-daily indinavir appears more efficacious than two-times-daily dosing when administered with zidovudine and lamivudine. Two-times-daily indinavir dosing should only be considered in situations characterized by favorable pharmacokinetic drug-drug interactions.

Timed-kill curves for Cryptococcus neoformans isolated from patients with AIDS

Infection with Cryptococcus neoformans is an increasing problem in immunocompromised patients, particularly those with acquired immune deficiency syndrome (AIDS). Amphotericin B and fluconazole are currently acceptable therapies for cryptococcal meningitis; however, their effects remain suboptimal and recurrence or treatment failure is still a problem. Antifungal susceptibility testing may be an important tool for guiding therapy, but for C. neoformans, a reliable method is still not available. This retrospective study evaluated minimal inhibitory concentration (MIC) for amphotericin B and fluconazole, and minimal fungicidal concentration (MFC) and timed-kill curves for amphotericin B against 16 clinical isolates of C. neoformans obtained from AIDS patients with cryptococcal meningitis. No correlation between clinical outcome and MIC was observed for amphotericin B. In selected cases, the MFC seemed to be a better predictor of outcome than MIC. In this study, amphotericin B timed-kill curves appeared to show a correlation with clinical outcome of the 16 patients with AIDS-associated cryptococcal meningitis. These in vitro tests must be further evaluated in prospective studies to confirm their potential usefulness for guiding cryptococcal meningitis therapy.

AIDS in Latin America

The epidemic in Latin America has placed an unexpected additional burden on the health care systems and national economies, already weak and affected by severe problems. Specific regional diseases in addition to common opportunistic infections, and particularly the high incidence of TB, produce a different picture compared with the United States and Europe. Access to ARV therapy is far from being universal in Latin America; nevertheless, some countries are providing HAART to all eligible patients, showing that it is not impossible to improve quality of care for people living with HIV infection in the region. Before assuming as definitive and irreversible that at least one or two generations will be sacrificed on the altar of inequity of our uneven world, we as acting scientists should join the struggle of millions of human beings claiming their right to be treated with the best drugs that science can offer today.

In vitro susceptibility studies of Cryptococcus neoformans isolated from patients with no clinical response to amphotericin B therapy

The in vitro activities of three antifungal drugs alone and in combination were evaluated against five isolates of Cryptococcus neoformans using time-kill curves (TKC). The isolates were from AIDS patients who had either died or had failed to show a clinical response during amphotericin B (AMB) treatment. AMB, fluconazole (FCZ) and flucytosine (5FC), and combinations of the drugs (AMB plus 5FC, AMB plus rifampicin (RIF) and FCZ plus 5FC), were evaluated. With all five isolates AMB did not show fungicidal activity; instead, a persistent or tolerant effect was observed. Combinations of AMB plus 5FC and AMB plus RIF showed a clear synergic effect, except for one isolate tested with AMB plus RIF. In contrast, the FCZ plus 5FC combination did not inhibit growth of any isolate.

Human immunodeficiency virus infection associated arthritis: clinical characteristics

OBJECTIVE

To define the frequency and characteristics of human immunodeficiency virus (HIV) associated arthritis.

METHODS

A total of 270 patients with HIV infection were prospectively evaluated for the presence of rheumatic complaints. Diagnosis of HIV infection was performed by ELISA and confirmed by Western blot, and all HIV patients were classified according to the US Centers for Disease Control criteria.

RESULTS

Twenty-one (7.8%) patients presented with HIV associated arthritis. Other arthritides including HLA-B27 related, such as Reiter's syndrome, psoriatic arthritis, and rheumatoid arthritis, were excluded. Seventeen were men and 4 women, with a mean age of 34.8 years (SD 11.1). Fourteen (66%) were homosexuals, 4 (19%) intravenous drug users, and 3 (14%) heterosexuals. Twelve (57%) were in stage IV, 5 (23%) in stage III, and 4 (9%) in stage II. Ten (47%) patients had oligoarticular involvement, 8 (38%) monoarticular, 2 (9%) asymmetric polyarthritis, and one (4%) symmetric polyarthritis. Rheumatoid factor and HLA-B27 antigen were negative in all (15) patients studied. The mean duration of arthritis was 2 weeks (1-24). No differences in duration of arthritis were found among the different risk factors (p = 0.811), HIV stages (p = 0.205), and type of articular involvement (p = 0.252). There was, however, a trend between the number of involved joints and stages of HIV infection (p = 0.13).

CONCLUSION

The pattern of joint involvement of HIV associated arthritis is similar to that of other viral disorders: acute onset, short duration, no recurrences, and no erosive changes.

Cerebral tumor-like American trypanosomiasis in acquired immunodeficiency syndrome

Cerebral tumor-like American trypanosomiasis (CTLAT) is an uncommon complication of Chagas' disease, observed only in immunosuppressed patients. We assessed 10 human immunodeficiency virus-positive patients with Chagas' disease who presented with CTLAT. All patients had neurological involvement and 6 developed intracranial hypertension. Neuroimaging studies showed supratentorial lesions in 9 patients, being single in 8. One case had infratentorial and supratentorial lesions. Low CD4+ cell counts were observed in all the cases and in 6 of them CTLAT was the first manifestation of acquired immunodeficiency syndrome. Serological tests for Chagas' disease were positive in 6 of 8 patients. Trypanosoma cruzi was identified in all brain specimens and in three cerebrospinal fluid samples. CTLAT should be considered in the differential diagnosis of intracranial mass lesions in human immunodeficiency virus-positive patients and should be added to the list of acquired immunodeficiency syndrome-defining illnesses.

Treatment of primary HIV infection: a pilot study of stavudine and didanosine plus nevirapine with or without hydroxyurea

Treatment of primary human immunodeficiency virus (HIV) infection (PHI) may provide an opportunity to achieve a long lasting suppression of viral replication. Although there is growing evidence of the benefit of treating PHI, clinical data are still very limited. Special therapeutic considerations in this clinical setting include the prevalence of resistant viruses in the community, complexity of regimens and their long-term toxicity. In addition, adjunctive therapies aimed at exploring the role of immune modulation and intensification of antiretroviral therapy are becoming areas of great interest. In this regard, the role of hydroxyurea, a cytostatic agent that potentiates the antiviral effect of didanosine, and possibly of stavudine is being investigated. A pilot study to assess the antiviral effect of a combination of didanosine plus stavudine plus nevirapine with or without hydroxyurea in the treatment of PHI is currently under way. Preliminary results on 22 patients who completed at least 36 weeks of therapy suggest that the combination is safe, well tolerated and effective for the treatment of PHI.

Prevalence of hepatitis viruses in an anti-human immunodeficiency virus-positive population from Argentina. A multicentre study

The objectives of this study were to investigate the prevalence of infections with hepatotrophic viruses in an anti-human immunodeficiency virus (HIV)-positive population from Buenos Aires and to compare it among the main risk groups for HIV infection. Four hundred and eighty-four consecutive patients attending the HIV outpatients clinic were studied: 359 men and 125 women, median age 29 years (range 16-67 years); 35.5% had presented acquired immune deficiency syndrome (AIDS)-defining conditions. Two hundred and thirty-four patients were intravenous drug users (IVDU), 99 had homosexual and 142 heterosexual preference, seven had received blood transfusions and two had no risk factors. Hepatitis B surface antigen (HBsAg), and antibodies to hepatitis B core antigen (HBcAb) and to hepatitis C virus (anti-HCV) were investigated in all patients; antibodies to HBsAg (HBsAb) and IgG antibodies to hepatitis D virus (anti-HDV) in all HBcAb-positive patients; hepatitis B e antigen and antibodies to HBeAg (HBeAg) in all HBsAg-positive patients; IgG antibodies to hepatitis A virus (anti-HAV) in the first 307 patients; and IgG antibodies to hepatitis E virus (anti-HEV) in the first 91 patients. As control groups, contemporary voluntary blood donors were studied for prevalence of HAV, HBV, HCV and HEV. The percentages of HBcAb, HBsAg, anti-HCV and anti-HEV (58.5, 14.5, 58.5 and 6.6%, respectively) were significantly higher in anti-HIV-positive patients than in control groups (3.2, 0.5, 1.0 and 1.8%, respectively) (P = 0.000). The prevalence of HBcAb was significantly higher in IVDU (72.6%) than in heterosexuals (33.8%) (P = 0.0001) and in homosexuals (59.6%) (P = 0.0189). The percentage of HBsAg was significantly higher in IVDU (19.2%) than in heterosexuals (6.3%) (P = 0.0004). Anti-HCV was significantly higher in IVDU (92.3%) than in homosexuals (14.1%) and in heterosexuals (33.1%) (P = 0.000 in both cases). The prevalence of anti-HDV was relatively low (1.9%). There was no difference in the percentage of anti-HAV between HIV-positive and negative subjects. In conclusion, there is a high prevalence of HBV and HCV infections in HIV-positive patients from our area. Drug use is the main route of transmission, but prevalence of HCV in patients with, probably, sexually acquired HIV infection is also higher than in the control group. The increased prevalence of HEV infection in HIV-positive individuals is another provocative finding that warrants further study.

Disseminated histoplasmosis with orofacial involvement in HIV-I-infected patients with AIDS: manifestations and treatment

INTRODUCTION

Histoplasmosis is a deep mycosis which is increasingly seen in HIV disease. It has emerged as a relatively common infection in Argentina, mainly in HIV-infected and other immunocompromised persons, and is often disseminated (DH).

OBJECTIVE

The aim of this study was to describe 32 HIV-I-seropositive patients with AIDS who had DH, 21 of whom presented orofacial manifestations, and their treatment.

SUBJECTS AND METHODS

A retrospective study of 876 HIV-seropositive patients revealed 32 with a clinical diagnosis of DH confirmed by special stains on histopathologic specimens, or by culture.

RESULTS

Thirty-two HIV-infected patients had DH. Two-thirds (21 patients) had oral lesions of histoplasmosis, of which six presented with oral cavity (OC) lesions as the sole orofacial manifestation of disease, nine patients presented oral and facial (OF) lesions and six presented facial lesions only. A unique case of submandibular histoplasmosis is also reported. Antifungal therapy cleared more than 90% of the orofacial and disseminated lesions of histoplasmosis. Over the 7-year period there was a mortality of 85%.

CONCLUSION

DH should be considered as a possible diagnosis in HIV patients with chronic ulcerative or nodular orofacial or oral lesions. Itraconazole is an effective and acceptable therapy.

[Diarrhea and AIDS: more complex diagnostic techniques; better therapeutic results]

During 17 months, 73 HIV-positive patients with diarrhea lasting at least for 14 days, were studied prospectively. The patients had stool specimen examinations negative for enteric pathogens, or positive for one of them, but with no response to specific treatment. All patients were subcomitted to digestive endoscopy and biopsies were taken for microbiological and histological studies. The etiology of the diarrhea could be established in 48 patients (66%). In 45, the cause was an enteric infection. There was association of 2 pathogens in 11 patients, and of 3 in 1 patient. The agents found were: Cryptosporidium (24%), MAI (16%), Giardia lambila (12%), isospora belli (5%), Shigella (5%), Salmonella (5%); Entamoeba histolytica (3%), HSV (3%), tuberculosis (2%), adherent bacteria (2%) and spirochetes (2%). In 3 patients the etiology was not infection, their diagnoses were coeliac disease, lymphoma and idiophatic colonic ulcers, respectively. In 51% of the cases only the examination of endoscopic biopsy specimens could identify the cause of the diarrhea. These results justify the use of these methods to improve diagnosis and therapeutic attempts in these patients.

Serologic evaluation of human immunodeficiency virus type 1-infected individuals from Argentina and the United States indicates a similar distribution of subgroup B isolates

Utilizing peptides based on the V3 region of gp120, we undertook a serologic examination of human immunodeficiency virus type 1 (HIV-1)-infected individuals from Argentina to determine if prevalent HIV-1 isolates could be identified in this population. Our findings suggest that a similar pool of HIV-1 subgroup B isolates exists in both Argentina and the United States.