Novel nelfinavir mesylate loaded d-α-tocopheryl polyethylene glycol 1000 succinate micelles for enhanced pediatric anti HIV therapy: In vitro characterization and in vivo evaluation.

Worldwide more than 35 million people are living with Human Immunodeficiency Virus (HIV) where 3.3 million are children. This translates in approximately 700 new daily infections in children only in 2012. Prolonged High Activity Antiretroviral Therapy (HAART) regimes could present low-patient compliance, especially in children, affecting therapeutic success. Nelfinavir mesylate (NFV) is a non-peptidic HIV-1 protease inhibitor (IP) which was the first IP recommended for pediatric use (>2 years-old). It exhibits pH-dependant aqueous solubility which results highly restricted at physiological pH values. The former represents a main clinical limitation due to the reduction on drug absorption along the small intestine after an oral administration, leading to unpredictable drug bioavailability. Moreover a liquid formulation of NFV is not available worldwide, preventing appropriate dose adjustment and more convenient administration. In this framework, the present investigation reports the development of a NFV highly concentrated aqueous formulation for a more appropriate management of pediatric anti-HIV therapy. The aim was to encapsulate NFV within D-α-tocopheryl polyethylene glycol 1000 succinate micelles to improve its aqueous solubility and its oral pharmacokinetic parameters. Results show that NFV aqueous solubility was increased up to 80.3 mg/mL. NFV-loaded micelles exhibited a hydrodynamic diameter of 5.6 nm and a spherical morphology as determined by dynamic light scattering and transmission electronic microscopy, respectively. In vitro NFV release profile demonstrated a cumulative drug release of 56% at 6 h. Finally, in vivo data showed a significant (p<0.01) increase of Area-Under-the-Curve between 0 and 24 h for NFV encapsulated in micelles in comparison with a NFV suspension prepared with glycerin 20% v/v and carboxymethylcellulose sodium 0.5% w/v, representing an increment on drug oral relative bioavailability of 1.71-fold. Thereby, this formulation represents an innovative nanotechnological platform to improve pediatric HIV pharmacotherapy.

Emergence of primary NNRTI resistance mutations without antiretroviral selective pressure in a HAART-treated child.

OBJECTIVE: The use of antiretrovirals (ARV) during pregnancy has drastically reduced the rate of the human immunodeficiency virus perinatal transmission (MTCT). As a consequence of widespread ARV use, transmission of drug resistant strains from mothers to their babies is increasing. Ultra-sensitive PCR techniques have permitted the quantification of minority viral populations, but little is known about the transmission of drug-resistant HIV-1 minority population in the setting of MTCT. METHODOLOGY/PRINCIPAL FINDINGS: We describe the case of a female child born to an HIV-infected mother, which had not taken any ARV during the pregnancy. The child's first genotype demonstrated a minor non-nucleoside reverse transcriptase inhibitor (K101E), and during her treatment with reverse transcriptase and protease inhibitors full resistance to non-nucleoside reverse transcriptase inhibitors (NNRTI) emerged (G190A). Phenotypic/genotypic analysis of variant quasispecies through yeast TyHRT assay was conducted to characterize minority resistant viral strains circulating in both mother and child. Maximum likelihood and Bayesian MCMC phylogenetic analyses were performed with samples from the pair to assess genetic relatedness among minor viral strains. The analysis showed that the child received a minor NNRTI resistant variant, containing the mutation K101E that was present in less than 1% of the mother's quasispecies. Phylogenetic analyses have suggested common ancestry between the mother's virus strain carrying K101E with the viral sequences from the child. CONCLUSION: This is the first documentation of MTCT of a minority resistant strain of HIV-1. The transmission of minor resistant variants carries the threat of emergence of multi-drug primary mutations without identified specific selective pressures.

Discordant genotypic interpretation and phenotypic role of protease mutations in HIV-1 subtypes B and G.

OBJECTIVES: HIV-1 group M is classified into nine different subtypes. Most antiretroviral (ARV) drugs have been developed for subtype B, and the response of non-B subtypes in terms of susceptibility and the acquisition of drug resistance when facing those drugs is largely unknown. In this study, we aimed to address differences in the impact of protease inhibitor (PI)-selected mutations on subtypes B and G. PATIENTS AND METHODS: ARV-treated, HIV-positive patients regularly monitored at the Hospital de Egas Moniz, in Lisbon, Portugal, were examined for the presence of PI-associated primary mutations (301 subtype B and 184 subtype G), and for the selection of those mutations over the time of PI exposure. Forty-three subtype G patients were phenotyped for susceptibility to all available PIs through VIRCO's Antivirogram, and compared with a similar dataset of subtype B patients. RESULTS: Mutation I54V/L was selected by nelfinavir in subtype G isolates, a mutation not previously described for this drug in subtype B. L90M was associated with a lower reduction in the susceptibility of subtype G to nelfinavir when compared with subtype B, and with no reduced susceptibility to saquinavir. This was compensated for by the acquisition of M89I in subtype G. L90M did not reduce the susceptibility of subtype G to saquinavir, in contrast to subtype B. Likewise, the pattern I54V/L-L90M did not reduce the susceptibility of subtype G to indinavir and saquinavir. Indinavir-associated mutations M46I/L, I84V and V82A/F/T developed earlier in subtype B across the time of exposure to that drug when compared with subtype G counterparts. CONCLUSIONS: Our results provide proof of principle and support the growing evidence that subtype-specific responses to ARVs exist. Data presented here highlight inconsistencies in current genotyping interpretation algorithms inadequately applied to all HIV-1 subtypes.

Persistence of genotypic resistance to nelfinavir among women exposed to prophylactic antiretroviral therapy during pregnancy.

We assessed the development of drug resistance in women exposed to antiretroviral therapy (ART) for prevention of mother-to-child transmission (PMTCT) after 24 weeks postpartum in a prospective cohort of HIV-1-infected women. HIV-1-infected women, who received prophylactic ART during pregnancy, had genotypic resistance testing performed at the start (T1) of and 24 weeks after ART interruption (T2). The women had CD4 counts >250 cells/ml and no AIDS defining conditions. Of the 30 eligible women, the median age was 27 years [25-75% interquartile range (IQR): 21-32] and the median gestational age of ART initiation was 22 weeks (IQR: 19-27): 19 (63.3%) received zidovudine (ZDV) plus lamivudine (3TC) plus nelfinavir (NFV). At entry, most women (96.7%) were asymptomatic (CDC93 A1/A2), with a median CD4 count of 446 (IQR: 353-686) and median viral load (VL) of 8560 copies/ml (IQR: 3,252-19,515). No HIV-1 vertical transmission was observed. HIV subtype B was the most prevalent (70%). The development of new mutations associated with ART resistance was analyzed at T2. NFV resistance was observed in 4 out of 17 (23.5%) patients exposed to this drug: two major mutations D30N (1/17) and L90M (1/17) and minor mutations (N88S, 2/17). Mutations on positions 44, 69, and 118 (1/28) were present on reverse transcriptase (RT) analysis. No new nonnucleoside reverse transcriptase inhibitor (NNRTI)-associated mutation was observed. In this cohort, ART regimens were very efficient at blocking HIV vertical transmission. However, the high rate of NFV-resistant mutations observed in the postpartum period indicates the need for discussion of ART choices during pregnancy and the potential impact on future therapeutic options for these women. Women previously exposed to ART for PMTCT who will start HIV treatment should have genotypic resistance testing performed.

Effects of antiretroviral agents during pregnancy on liver enzymes and amylase in HIV-exposed, uninfected newborn infants.

This study assessed the effect of antiretroviral drugs administered to pregnant women on amylase and liver enzymes of the neonate. A prospective study was conducted on 52 neonates divided into three groups: infants born to HIV-infected mothers taking zidovudine (ZDV group, n = 18), infants born to mothers taking zidovudine + lamivudine + nelfinavir (TT group, n = 22) and infants born to normal women (control group, n = 12). Umbilical cord blood from the newborn infant was used to determine liver transaminases and amylase. Data were analyzed statistically by nonparametric tests, with the level of significance set at p<0.05. The median levels for TT group newborns were 33.3 U/L for oxaloacetic transaminase, 21.5 U/L for pyruvic transaminase, 1.9 mg/dL for total bilirubin, 153 mg/dL for alkaline phosphatase, and 9.6 U/L for amylase. These results did not differ from those obtained for Control newborns or newborns exposed to ZDV alone. No association was observed between the use of antiretroviral drugs during pregnancy and adverse effects on neonatal amylase and hepatic parameters at birth.

Antiretroviral agents and acid-base balance at delivery of the neonate.

Limited evidence is available regarding antiretroviral (ARV) safety for uninfected infants exposed to these drugs in utero. Our objective was to determine if ARV administered to pregnant women is associated with decreasing umbilical arterial pH and base excess in uninfected infants. A prospective study was conducted on 57 neonates divided into three groups: ZDV group, born to mothers taking zidovudine (N = 20), triple therapy (TT) group, born to mothers taking zidovudine + lamivudine + nelfinavir (N = 25), and control group (N = 12), born to uninfected mothers. Umbilical cord blood was used to determine umbilical artery gases. A test was performed to calculate the sample by comparing means by the unpaired one-tailed t-test, with alpha = 0.05 and beta = 20%, indicating the need for a sample of 18 newborn infants for the study groups to detect differences higher than 20%. The control and ARV groups were similar in gestational age, birth weight, and Apgar scores. Values of pH, pCO2, bicarbonate, and base excess in cord arterial blood obtained at delivery from the newborns exposed to TT were 7.23, 43.2 mmHg, 19.5 mEq/L, and -8.5 nmol/L, respectively, with no significant difference compared to the control and ZDV groups. We conclude that intrauterine exposure to ARV is not associated with a pathological decrease in umbilical arterial pH or base excess. While our data are reassuring, follow-up is still limited and needs to be continued into adulthood because of the possible potential for adverse effects of triple antiretroviral agents.

Antiretroviral agents and acid-base balance at delivery of the neonate

Limited evidence is available regarding antiretroviral (ARV) safety for uninfected infants exposed to these drugs in utero. Our objective was to determine if ARV administered to pregnant women is associated with decreasing umbilical arterial pH and base excess in uninfected infants. A prospective study was conducted on 57 neonates divided into three groups: ZDV group, born to mothers taking zidovudine (N = 20), triple therapy (TT) group, born to mothers taking zidovudine + lamivudine + nelfinavir (N = 25), and control group (N = 12), born to uninfected mothers. Umbilical cord blood was used to determine umbilical artery gases. A test was performed to calculate the sample by comparing means by the unpaired one-tailed t-test, with a = 0.05 and ß = 20 percent, indicating the need for a sample of 18 newborn infants for the study groups to detect differences higher than 20 percent. The control and ARV groups were similar in gestational age, birth weight, and Apgar scores. Values of pH, pCO2, bicarbonate, and base excess in cord arterial blood obtained at delivery from the newborns exposed to TT were 7.23, 43.2 mmHg, 19.5 mEq/L, and -8.5 nmol/L, respectively, with no significant difference compared to the control and ZDV groups. We conclude that intrauterine exposure to ARV is not associated with a pathological decrease in umbilical arterial pH or base excess. While our data are reassuring, follow-up is still limited and needs to be continued into adulthood because of the possible potential for adverse effects of triple antiretroviral agents.

Effects of antiretroviral agents during pregnancy on liver enzymes and amylase in HIV-exposed, uninfected newborn infants

This study assessed the effect of antiretroviral drugs administered to pregnant women on amylase and liver enzymes of the neonate. A prospective study was conducted on 52 neonates divided into three groups: infants born to HIV-infected mothers taking zidovudine (ZDV group, n = 18), infants born to mothers taking zidovudine + lamivudine + nelfinavir (TT group, n = 22) and infants born to normal women (control group, n = 12). Umbilical cord blood from the newborn infant was used to determine liver transaminases and amylase. Data were analyzed statistically by nonparametric tests, with the level of significance set at p<0.05. The median levels for TT group newborns were 33.3 U/L for oxaloacetic transaminase, 21.5 U/L for pyruvic transaminase, 1.9 mg/dL for total bilirubin, 153 mg/dL for alkaline phosphatase, and 9.6 U/L for amylase. These results did not differ from those obtained for Control newborns or newborns exposed to ZDV alone. No association was observed between the use of antiretroviral drugs during pregnancy and adverse effects on neonatal amylase and hepatic parameters at birth.

Effect of antiretroviral agents on carbohydrate metabolism in HIV-1 infected pregnant women.

BACKGROUND: Despite the correlation between the use of protease inhibitors (PI) and adverse metabolic glycemic events, no prospective study has examined these parameters in pregnant women who use these drugs. METHODS: A prospective study was conducted on 57 pregnant women to investigate the effect of antiretroviral drugs (ARV) on the carbohydrate metabolism during pregnancy. The women were divided into three groups: ZDV Group, 20 HIV-1 infected women taking ZDV; TT Group, 25 patients on triple antiretroviral treatment (ZDV + 3TC + NFV); and Control Group, 12 pregnant women. Blood samples were obtained during the first visit for the determination of fasting plasma glycemia, when the patients were also submitted to a 75 g oral glucose test (OGTT-75g). These procedures were performed four times along pregnancy. RESULTS: The median values of the area under the glycemia curve (AUC) determined over a period of 120 min between the 33rd and 38th week were 11 685 mg/dL for the Control Group, 13 477 mg/dL for the ZDV Group, and 13 650 mg/dL for the TT Group (p = 0.049). There was an increase in the AUC along pregnancy for all three groups studied, regardless of the treatment used, although this increase was significant only in the TT Group (p = 0.001). The antiretroviral agents had no deleterious effects on prematurity, low birth weight, intrauterine growth restriction rates, or on Apgar score. CONCLUSION: An association was detected between the use of PI and the development of carbohydrate intolerance during pregnancy. The antiretroviral agents had no deleterious effects on perinatal prognosis.

Genital HIV-1 viral load is correlated with blood plasma HIV-1 viral load in Brazilian women and is reduced by antiretroviral therapy.

CONTEXT: Cervicovaginal secretions represent the primary vehicle in mother to infant and sexual HIV-1 transmission. Understanding the viral dynamics in this compartment is important to improve interventions to decrease HIV transmission. OBJECTIVES: To evaluate the correlation of HIV-1 blood plasma viral load and cervicovaginal HIV-1 viral load and the effect of antiretroviral therapy (ART) on cervicovaginal HIV-1 viral load. METHODS: A cross-sectional study among HIV-1 infected women recruited between February 2002 and January 2003 and a longitudinal study that included 11 women who initiated ART were performed. HIV-1 viral load was measured in the female genital tract and in blood plasma using the Nuclisens assay before and 1 month after ART introduction. RESULTS: HIV-1 viral load in cervicovaginal lavage was significantly correlated with HIV-1 blood plasma viral load (n = 27, Spearman rho = 0.73, p<0.001). In the longitudinal study, antiretroviral therapy was associated with a reduction of 1.44 log10 on genital HIV-1 viral load (95% CI = 0.57-2.30, p = 0.004, Student's t-test). CONCLUSIONS: HIV-1 viral load in female genital secretions is correlated with blood plasma HIV-1 viral load. Antiretroviral therapy substantially reduces HIV-1 viral load in the female genital tract.

HIV-1 genotypes related to failure of nelfinavir as the first protease inhibitor treatment.

Combined antiretroviral therapy results in sustained viral suppression and a decrease in mortality and morbidity due to HIV infection. Intrinsic strength, durability and absence of cross-resistance are key factors in the selection of antiretrovirals. Failure with nelfinavir has been associated with two protease gene mutations, D30N and L90M. The D30N mutation does not result in cross-resistance with other protease inhibitors, and it decreases viral fitness. In order to check for this mutation after failure with nelfinavir, the 246 HIV-1 genotyping test was performed on virus samples from 55 patients with failure of nelfinavir as the first protease inhibitor. Most (84%) of the viral strains were of subtype B. Nucleosides associated with mutations (NAM) were observed in 80% of the tests; no INS69, complex 151, K65R and L74V mutations, which give multi-resistance to nucleoside analogue reverse transcriptase inhibitors to tenofovir and DDI, respectively, were observed. In the tests for protease gene mutations, the D30N mutation was found in 57%, L90M in 18% and the wild-type virus in 25%. These data are similar to published reports, showing that alternative therapies used after failure with nelfinavir may be more successful, as the D30N mutation does not cause cross-resistance to other protease inhibitors.

HIV-1 genotypes related to failure of nelfinavir as the first protease inhibitor treatment

Combined antiretroviral therapy results in sustained viral suppression and a decrease in mortality and morbidity due to HIV infection. Intrinsic strength, durability and absence of cross-resistance are key factors in the selection of antiretrovirals. Failure with nelfinavir has been associated with two protease gene mutations, D30N and L90M. The D30N mutation does not result in cross-resistance with other protease inhibitors, and it decreases viral fitness. In order to check for this mutation after failure with nelfinavir, the 246 HIV-1 genotyping test was performed on virus samples from 55 patients with failure of nelfinavir as the first protease inhibitor. Most (84 percent) of the viral strains were of subtype B. Nucleosides associated with mutations (NAM) were observed in 80 percent of the tests; no INS69, complex 151, K65R and L74V mutations, which give multi-resistance to nucleoside analogue reverse transcriptase inhibitors to tenofovir and DDI, respectively, were observed. In the tests for protease gene mutations, the D30N mutation was found in 57 percent, L90M in 18 percent and the wild-type virus in 25 percent. These data are similar to published reports, showing that alternative therapies used after failure with nelfinavir may be more successful, as the D30N mutation does not cause cross-resistance to other protease inhibitors.

Effect of antiretroviral drugs on maternal CD4 lymphocyte counts, HIV-1 RNA levels, and anthropometric parameters of their neonates.

PURPOSE: To study the effect of antiretroviral drugs administered during pregnancy on CD4 lymphocyte counts and HIV-1 RNA levels of pregnant women and on the anthropometric parameters of their neonates. METHODS: A prospective study was conducted on 57 pregnant women and their neonates divided into 3 groups: ZDV Group, HIV-infected mothers taking zidovudine (n=20); triple therapy (TT) Group, mothers taking zidovudine+lamivudine+nelfinavir (n=25), and Control Group, normal women (n=12). CD4 lymphocyte counts and HIV-1 RNA levels of pregnant women were analyzed during two periods of pregnancy. The perinatal prognosis took into account preterm rates, birth weight, intrauterine growth restriction, perinatal death, and vertical transmission of HIV-1. Data were analyzed statistically using the nonparametric chi-square, Mann-Whitney, Friedman, Kruskal-Wallis, and Wilcoxon matched pairs tests, with the level of significance set at P<.05. RESULTS: The major maternal demographic and anthropometric data were homogeneous for the various groups. HIV-1 viral burden, which was initially elevated, median of 14,370 copies/mL, was significantly reduced in the TT group, reaching 40 copies/mL. With respect to T-CD4+ lymphocyte counts, there was a significant recovery in Group TT at the end of pregnancy, this value being significantly different from that for the ZDV group (P=0052). There was no difference between groups regarding gestation length, Apgar scores, or neonatal anthropometric classification. There was no case of vertical HIV-1 transmission. CONCLUSIONS: The results obtained for the present series demonstrate the efficiency and suggest safety of the use of antiretroviral drugs during pregnancy as revealed by anthropometric parameters of the neonate.

Effect of antiretroviral drugs on maternal CD4 lymphocyte counts, HIV-1 RNA levels, and anthropometric parameters of their neonates

OBJETIVOS: Estudar o efeito das drogas anti-retrovirais sobre a quantificação dos linfócitos TCD4 e RNA do HIV-1 de gestantes portadoras do HIV-1 e parâmetros antropométricos de seus neonatos. MÉTODOS: Estudo prospectivo avaliando 57 gestantes e seus neonatos em três grupos: Grupo AZT, gestantes portadoras do HIV utilizando zidovudina (n=20); Grupo TT, mães utilizando zidovudina+lamivudina+nelfinavir (n=25), e Grupo Controle, mulheres saudáveis (n=12). A quantificação dos linfócitos TCD4 e RNA do HIV-1 de gestantes portadoras do HIV foi analisada em dois períodos durante a gestação. O prognóstico perinatal levou em consideração as taxas de pré-termos, restrição de crescimento intra-útero, mortalidade perinatal e transmissão vertical do HIV-1. Os dados foram analisados utilizando-se testes não paramétricos de qui-quadrado, Mann-Whitney, Friedman, Kruskal-Wallys e Wilcoxon para amostras pareadas, considerando-se significativos valores associados a p<0,05. RESULTADOS: Observou-se homogeneidade entre os dados demográficos e antropométricos de realce. A carga viral, inicialmente elevada (14.370 cópias/ml), reduziu-se significativamente no grupo com tratamento tríplice , chegando a 40 cópias/ml. Quanto à contagem de linfócitos CD4, observou-se recuperação significativa nas pacientes do grupo TT, no final da gestação, sendo esse valor significativamente diferente em comparação ao grupo AZT (p = 0,0052). Não se observou diferença entre os grupos quanto à duração da gestação, aos índices de Apgar, e à classificação antropométrica neonatal. Não houve nenhum caso de transmissão vertical do HIV-1. CONCLUSÕES: Os resultados obtidos na presente casuística demonstram eficiência e sugerem segurança no uso de anti-retrovirais na gestação sobre parâmetros antropométricos dos neonatos.

Alternative, age- and viral load-related routes of nelfinavir resistance in human immunodeficiency virus type 1-infected children receiving highly active antiretroviral therapy.

To assess prevalence of nelfinavir resistance mutations in children receiving highly active antiretroviral therapy, sequencing of protease gene from plasma of 53 human immunodeficiency virus-infected children was performed. The prevalence of L90M was similar to that of D30N. There was a significant correlation with a higher viral load and lower age and the occurrence of L90M. These findings suggest differential molecular age- and viral load-related routes for nelfinavir resistance.

Maintaining the nelfinavir trough concentration above 0.8 mg/L improves virologic response in HIV-1-infected children.

Differences in virologic response were compared in 32 HIV-infected children with a nelfinavir trough concentration either below (n=7) or above (n=25) 0.8 mg/L. Virologic response at week 48 was observed in 29% of children with subtherapeutic nelfinavir troughs versus 80% in children with therapeutic nelfinavir troughs (P=.02).

The NEAT study: a 48-week open-label study to compare the antiviral efficacy and safety of GW433908 versus nelfinavir in antiretroviral therapy-naive HIV-1-infected patients.

OBJECTIVE: To compare the efficacy, durability, and tolerability of GW433908 (908), 1400 mg twice-daily (BID), with nelfinavir (NFV), 1250 mg BID. METHODS: This was an international, multicenter, randomized, open-label study (NEAT) in antiretroviral therapy (ART)-naive HIV-infected adults with plasma HIV-1 RNA (vRNA) at screening > or =5000 copies/mL (c/mL). Patients were randomly assigned to 908 or NFV (2:1) for a minimum of 48 weeks, with a background of abacavir (ABC) and lamivudine (3TC). RESULTS: A total of 166 patients received randomized treatment with 908 BID and 83 received NFV BID. The population was diverse with regard to race and gender (76% Hispanics and blacks, 31% female) and had advanced HIV disease at screening (45% had vRNA >100,000 c/mL, 48% had CD4 cell counts <200 cells/mm3, 20% had a history of Centers for Disease Control class C events). After 48 weeks of study by an intention-to-treat rebound or discontinuation = failure analysis, a greater proportion of patients in the 908 BID group (66%) than the NFV BID group (51%) achieved vRNA <400 c/mL. Furthermore, more patients with screening vRNA >100,000 c/mL (67 vs. 35%) or CD4 <50 cells/mm3 (48 vs. 24%) achieved undetectable viral loads taking 908 BID compared with NFV BID, respectively. Favorable immunologic responses were observed for both groups. Diarrhea, which was more common in the NFV BID group (18 vs. 5%), was the only drug-related grade 2-4 adverse event with a significant difference (P = 0.002) in incidence between groups. CONCLUSION: Administration of 908 BID resulted in a potent and sustained antiretroviral response, notably in ART-naive patients with advanced HIV disease. GW433908 was generally well tolerated and provides a convenient dosing option without food or fluid restrictions.

Genotype and phenotype at baseline and at failure in human immunodeficiency virus-infected antiretroviral-naive patients in a randomized trial comparing zidovudine and lamivudine plus nelfinavir or nevirapine.

For the 127 Spanish patients enrolled in the Combine Study, a resistance substudy was performed with 100 (79%) plasma samples obtained at baseline and with 18 samples obtained from 19 patients at the time they experienced treatment failure. At baseline, primary mutations to nonnucleoside reverse-transcriptase inhibitors and protease inhibitors were not detected, whereas mutations to nucleoside reverse-transcriptase inhibitors were observed in 10% of patients. At failure, mutations were detected in 7 of 16 patients. An agreement in the results of virtual and real phenotypes was observed in the 93 samples in which both tests were performed.

Estimating the length of the first antiretroviral therapy regiment durability in Säo Paulo, Brazil

Brazil was the first country to provide unrestricted, cost-free access to antiretroviral (ARV) medicine for AIDS treatment. However, there is little data about the benefits of such a policy for these patients. We evaluated the duration of benefit obtained with the introduction of ARVs, defined as the durability of the first ARV regiment. We reviewed the medical charts of patients attended from 1996-2000, at the outpatient clinics of the Federal University of Säo Paulo, Brazil. A total of 120 drug-naive HIV-1 infected patients were eligible to participate in the study. About half of the individuals (53 percent) presented with disease symptoms; 59 percent of them had CD4 count below 200 cells/mm³. Mean estimated duration of the benefit of therapy was 14.1 months. The most used regimen in this cohort was Zidovudine/3TC/Indinavir (26 percent), followed by Zidovudine/DDI (17 percent), and Zidovudine/3TC/Nelfinavir (13 percent). The most frequent cause of interruption of therapy was gastrointestinal intolerance. Use of treatment regimens with three drugs was more effective than with two drugs, but only for patients with CD4<200 cells/mm³ or CV>100,000 copies RNA/mL. However, the use of triple therapy was associated with a significantly higher probability of reaching maximum viral suppression, during a longer period (p<0.05).The patients enrolled in the study benefitted from therapy for a limited time, after the introduction of double or triple antiretroviral therapy. The incidence of adverse events was significantly associated with loss of the benefits provided by the initial therapeutic regimen.

A randomized clinical trial comparing nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients (the Combine Study).

BACKGROUND: Non-nucleoside reverse transcriptase inhibitor-containing regimens may be a valid alternative to protease inhibitor-containing regimens for initial antiretroviral therapy, but to date few studies comparing these two strategies have been performed. OBJECTIVE: To evaluate the efficacy and safety of nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients. DESIGN: Randomized, open-label, multicentre trial. SETTING: Twelve centres in Spain (9) and Argentina (3). PATIENTS: One hundred and forty-two HIV-infected naive patients without AIDS. INTERVENTIONS: Patients received combivir (zidovudine 300 mg/lamivudine 150 mg, twice-daily) plus either nelfinavir (1250 mg) twice-daily (zidovudine/lamivudine/nelfinavir, n=70) or nevirapine (200 mg) twice-daily (zidovudine/lamivudine/nevirapine, n=72), and were followed for 12 months. The primary endpoint was the proportion of patients with a plasma HIV-1 RNA (pVL) of less than 200 copies/ml by PCR at 12 months. pVL of less than 20 copies/ml (PCR), changes in CD4 counts, clinical progression and adverse events were also evaluated. Efficacy was assessed using intent-to-treat (ITT) (missing=failure) and on-treatment analysis. RESULTS: At 12 months in the ITT analysis the proportion of patients with pVL below 200 copies/ml was 60% (95% CI 48.5-71.5) in the zidovudine/lamivudine/nelfinavir arm and 75% (95% CI 65-85) in the zidovudine/lamivudine/nevirapine arm (P=0.06), and the proportion below 20 copies/ml was 50% (95% CI 38.3-61.7) and 65% (95% CI 54.2-76.2), respectively (P=0.06). No differences were found when comparing the subgroup of patients with baseline pVL of more than 100,000 copies/ml. A gain of +173 and +162 CD4 cells/mm3, respectively, was observed. Zidovudine/lamivudine/nelfinavir was discontinued in 21% of patients, and zidovudine/lamivudine/nevirapine in 25%, due to toxicity (P>0.2). CONCLUSIONS: Our results suggest that zidovudine/lamivudine/nevirapine is at least as effective as zidovudine/lamivudine/nelfinavir as first-line therapy for HIV disease.