Saquinavir exposure in HIV-infected patients with chronic viral hepatitis

OBJECTIVES

The aim of this study was to assess the influence of hepatitis B virus or hepatitis C virus co-infection and the extent of liver fibrosis on saquinavir and ritonavir pharmacokinetics in HIV-infected subjects without liver function impairment.

METHODS

A cross-sectional, comparative study enrolling HIV-infected adults receiving saquinavir/ritonavir 1000/100 mg twice daily or 1500/100 mg once daily was conducted. Patients with chronic viral hepatitis (HEP+) were grouped as having advanced liver fibrosis (HEP+/FIB+) or not (HEP+/FIB-) based on the FIB-4 index. Saquinavir and ritonavir trough concentrations (C(trough)) in plasma were determined by HPLC. The geometric mean ratio (GMR) was used to compare saquinavir and ritonavir C(trough) between HEP- and HEP+ patients, and the influence of the extent of liver fibrosis on saquinavir and ritonavir pharmacokinetics was explored using analysis of variance.

RESULTS

One hundred and thirty-eight patients on twice-daily saquinavir/ritonavir (67 HEP-, 71 HEP+) and 36 patients on once-daily saquinavir/ritonavir (12 HEP-, 24 HEP+) were included. Saquinavir C(trough) was comparable between HEP- and HEP+ patients receiving either saquinavir/ritonavir 1000/100 mg twice daily [GMR 0.91, 95% confidence interval (CI) 0.60-1.37; P = 0.655] or 1500/100 mg once daily (GMR 0.88, 95% CI 0.39-1.97; P = 0.752). Similarly, ritonavir C(trough) was also comparable between HEP- and HEP+ patients. The extent of liver fibrosis was not significantly related to saquinavir or ritonavir C(trough) in patients receiving either of the two studied doses.

CONCLUSIONS

Saquinavir C(trough) was not increased in HIV-infected patients with chronic viral hepatitis in the absence of liver function impairment. These results confirm that no specific dose modification of saquinavir/ritonavir should be recommended in this setting.

Pneumocystis jirovecii pneumonia in Spanish HIV-infected patients in the combined antiretroviral therapy era: prevalence of dihydropteroate synthase mutations and prognostic factors of mortality

The incidence of Pneumocystis jirovecii pneumonia (PCP) in HIV-infected patients has decreased thanks to sulfa prophylaxis and combined antiretroviral therapy. The influence of P. jirovecii dihydropteroate synthase (DHPS) gene mutations on survival is controversial and has not been reported in Spain. This prospective multicenter study enrolled 207 HIV-infected patients with PCP from 2000 to 2004. Molecular genotyping was performed on stored specimens. Risk factors for intensive care unit (ICU) admission and mortality were identified using a logistic regression model. Seven patients (3.7%; 95% confidence interval [CI], 1.5-7.5%) had DHPS mutations. Overall mortality was 15% (95% CI, 10-21%), rising to 80% (95% CI, 61-92%) in patients requiring mechanical ventilation. None of the patients with DHPS mutants died, nor did they need ICU admission or mechanical ventilation. PaO(2) <60 mm Hg at admission was a predictor of ICU admission (P = 0.01), and previous antiretroviral therapy predicted non-ICU admission (P = 0.009). PaO(2) <60 mm Hg at admission and ICU admission during the 1st week were predictors of mortality (P = 0.03 and P < 0.001, respectively). The prevalence of DHPS mutants in Spain is low and is not associated with a worse outcome. Severe respiratory failure at admission is the strongest predictor of PCP outcome.

Bacterial pneumonia in HIV-infected patients: use of the pneumonia severity index and impact of current management on incidence, aetiology and outcome

OBJECTIVES

Despite a recent decrease, bacterial pneumonia (BP) is still the most common admission diagnosis in HIV patients. We analyse BP incidence, characteristics and prevention measures.

METHODS

Observational study of all patients hospitalized for BP in a tertiary hospital in Barcelona, Spain, from January 2000 to December 2005. Demographic and HIV-related data, BP risk factors, characteristics of BP and outcomes are analysed.

RESULTS

One hundred and eighty-six BP episodes in 161 patients were included; patients were mainly male (73.7%) and intravenous drug users (73.7%). A decrease in BP incidence was seen during the study period, especially in vaccinated patients. The most commonly isolated microorganism was Streptococcus pneumoniae (31.7%), followed by Legionella pneumophila (5.9%). Legionella pneumophila was more likely in patients with undetectable viral load, higher CD4 cell counts or prior vaccination. Highly active antiretroviral therapy, cotrimoxazole prophylaxis and pneumococcal vaccination did not have a significant influence on bacteraemia rate, in-hospital complications or BP mortality. High Pneumonia Severity Index (PSI) predicted mortality accurately [relative risk 15.2, 95% confidence interval 3.2-71.7; P=0.001]. Mortality was 9.1%, but was significantly higher in patients with CD4 counts under 200 cells/microL (P=0.022).

CONCLUSIONS

A decline in BP incidence was seen during the study period. Combining CD4 cell count and PSI score could become a good strategy in deciding which patients have to be hospitalized.

Leishmania infantum DNA detection in urine from patients with visceral leishmaniasis and after treatment control

A urine-polymerase chain reaction (PCR) assay was validated for diagnosis of human visceral leishmaniasis (VL), taking advantage of the accessibility of urine samples. Leishmania infantum DNA presence was examined in 17 urine samples from 17 patients with VL during a clinical episode and in 55 urine samples from 17 patients with VL monitored after treatment at different intervals. Fifty-nine urine samples from 59 controls with no history of VL were also studied. The urine-PCR test was positive in 15/17 samples obtained during the episode (sensitivity, 88%). None of the controls tested were urine-PCR positive (specificity, 100%). During the monitoring period, 25% of the samples gave a positive urine-PCR. Results were compared with other diagnostic methods, such as urine antigen detection and peripheral blood-PCR and culture, with good concordance during the clinical episode and differences in the follow-up period. This study suggests that urine-PCR is sensitive for diagnosis and may be useful to monitor treatment efficacy.

Efficacy of recombinant interleukin-2 (rIL-2) in patients with advanced HIV-1 infection and blunted immune response to HAART

OBJECTIVE

The efficacy of recombinant interleukin-2 (rIL-2) was assessed in HIV-infected patients with advanced immune suppression and a discordant immune response to highly active antiretroviral therapy (HAART). The primary endpoint was median change in CD4+ T-cell counts at the end of treatment as compared to baseline. Secondary endpoints were safety and changes in the various T-cell subpopulations.

MATERIAL AND METHODS

In a prospective cohort study, 19 patients with HIV-RNA < 50 copies/mL and < 200 CD4+ T cells/mm3 without a significant increase in the previous 12 months were scheduled to receive 6 cycles of 4.5 x 10(6) IU subcutaneous rIL-2 daily for 5 consecutive days, every 4 weeks.

RESULTS

Median age was 43 years, and 64% had a previous AIDS-defining event. Median nadir and baseline CD4+ cell counts were 36 and 99 cells/mm3, respectively. Three patients discontinued treatment and one experienced grade 4 side effects. CD4+ T-cell counts increased to 147 cells/mm3 (range, 24-285) at 1 month following completion of treatment (P = 0.002), and 180 cells/mm3 (range, 38-280) at 18 months (P < 0.001). This improvement was associated with a significant decrease in expression rates of the activation markers, HLA-DR and CD38.

CONCLUSION

Our results suggest that in patients with advanced HIV-infection showing a blunted immune response to HAART, rIL-2 might increase the pool of CD4+ T-cells by down-regulating the status of immune activation.

First-line antiretroviral therapy with efavirenz or lopinavir/ritonavir plus two nucleoside analogues: the SUSKA study, a non-randomized comparison from the VACH cohort

BACKGROUND

Efavirenz and lopinavir/ritonavir are both recommended antiretroviral agents for combination first-line therapy, although information on direct comparisons between them is scarce. A retrospective longitudinal study from the VACH cohort comparing both regimens was performed.

METHODS

Efficacy was examined comparing time to virological failure, CD4 recovery and clinical progression. Tolerability was examined comparing time to treatment discontinuation for any reason and for toxicity. Survival analysis was conducted using the Kaplan-Meier method, and standard and weighted Cox regression models.

RESULTS

A total of 1550 antiretroviral-naive patients starting a two-nucleoside reverse transcriptase inhibitor regimen plus either efavirenz (n = 1159) or lopinavir/ritonavir (n = 391) were included in the study. At baseline, patients starting lopinavir/ritonavir had higher HIV-1 RNA and lower CD4+ cell counts. There was no difference in the adjusted hazards of virological failure [efavirenz versus lopinavir/ritonavir hazard ratio (HR) = 0.93, 95% confidence interval (CI): 0.77-1.12, P = 0.43], CD4 recovery (HR = 1.11, 95% CI: 0.95-1.30, P = 0.19) and clinical progression (HR = 0.71, 95% CI: 0.39-1.31, P = 0.27). There was an increased risk of discontinuation for any reason or for toxicity for lopinavir/ritonavir (HR = 2.10, 95% CI: 1.40-3.15, P = 0.0003). CD4 recovery with both drugs was also similar in the lowest CD4 strata. A higher risk of early hypertriglyceridaemia was associated with lopinavir/ritonavir-based regimens.

CONCLUSIONS

Our study suggests similar virological efficacy for efavirenz- or lopinavir/ritonavir-based first-line antiretroviral regimens, but an increased risk of discontinuation because of toxicity in case of lopinavir/ritonavir-based therapy. Immunological outcome appeared similar with both regimens.

Early Monitoring of Ribavirin Serum Concentration is not Useful to Optimize Hepatitis C Virus treatment in HIV-Coinfected Patients

Background

Emerging data suggest that higher ribavirin (RBV) exposure could improve early hepatitis C virus (HCV) response. Furthermore, interindividual RBV bioavailability shows high variation, and dose-limiting haemolytic anaemia is a common adverse event. Therefore, it has been suggested that monitoring RBV serum levels could be used to drive dose modification and to optimize management of HCV-infected patients receiving combination treatment.

Methods

To assess the effect of RBV serum levels on HCV RNA clearance at week 4 and 12 of treatment, and to determine the correlation between RBV serum concentration and haemoglobin decrease, RBV trough levels were measured by HPLC in stored serum samples obtained from 94 HCV-HIV-coinfected patients at week 4 and 12 of treatment with peginterferon-α2b (1.5 μg/kg/weekly) plus ribavirin (800–1,200 mg/day).

Results

The median RBV levels increased from 1.70 μg/ml at week 4 to 1.97 μg/ml at week 12 of treatment ( P=0.001) and were independently predicted by weight-adjusted dose of RBV and co-administration of tenofovir. Haemoglobin drop was higher among patients who received zidovudine and weakly correlated with RBV level. Although RBV concentration was lower in genotype 1 or 4 HCV-infected patients who cleared the virus at treatment week 4, the ability of this parameter to discriminate between responders and non-responders at treatment week 4 and 12 was poor.

Conclusion

Intracellular RBV accumulation early in treatment might improve the kinetics of HCV response in difficult to treat patients. Although this hypothesis and the potential interaction between RBV and tenofovir warrant further research, our data do not support RBV serum monitoring as a tool to optimize treatment in HCV-HIV-coinfected patients.

Efficacy of liposomal amphotericin B for secondary prophylaxis of visceral leishmaniasis in HIV-infected patients

BACKGROUND AND OBJECTIVES

Visceral leishmaniasis (VL) is characterized by frequent relapses in HIV-infected patients, even in those who receive secondary prophylaxis. The aim of our study was to evaluate the efficacy of liposomal amphotericin B (L-AMB) for secondary prophylaxis of VL in HIV-infected patients.

METHODS

From January 2001 to December 2005, 17 HIV patients, with at least one previous episode of VL who received L-AMB as secondary prophylaxis for VL, were included in the study. Efficacy was measured as the proportion of patients remaining free (non-relapse) of VL at different time points. Relapses were analysed as time-to-relapse distribution and were evaluated by survival analysis using the Kaplan-Meier method.

RESULTS

Twenty-one episodes of VL were diagnosed and nine relapsed. The median follow-up time was 14 (5-44) months. The probability of remaining free of relapse at 6 months was 89.7% (95% CI, 76.2-100); at 12 months, the probability was 79.1% (95% CI, 61-97.2) and at 24 and 36 months, the probability was 55.9% (95% CI, 30.5-81.3). In the non-relapsing group, patients had a significant increase in CD4 cell levels of 102 (10-174) and 126 (4-159) cells/mm(3) at 12 and 24 months, respectively (P = 0.037), whereas in the relapsing group, no significant increase was observed. Prophylaxis with L-AMB was well tolerated and only three patients had a mild impairment of renal function without requiring any change in treatment.

CONCLUSIONS

L-AMB is well tolerated and useful for secondary prophylaxis of VL.

Systematic review of clinical trials evaluating low doses of stavudine as part of antiretroviral treatment

Stavudine is a nucleoside analogue used for the treatment of HIV-1 infection, as part of highly active antiretroviral treatment. In developing countries, stavudine is used widely, owing to low cost and inclusion in generic fixed-dose combinations. In developed countries, stavudine is now rarely used, although it is highly effective. This is because newer drugs show lower rates of mitochondrial toxicities, such as lipoatrophy, peripheral neuropathy and lactic acidosis. In the development of stavudine, there was evidence that a dosage of 20-30 mg b.i.d. was effective, but the 40-mg b.i.d. dose gained regulatory approval. This review analyses the clinical trials conducted before and after the regulatory approval of stavudine, and shows that the dose of 30 mg b.i.d. has equivalent antiviral efficacy (given the caveats of meta-analysis), with some evidence of lower rates of peripheral neuropathy and lipoatrophy. With limited resources for HIV-1 treatment in developing countries, and only 25% of eligible patients receiving highly active antiretroviral treatment, low-cost treatment options such as stavudine still need to be pursued, if safety can be improved by dose optimisation.