Gerrit-Jan Weverling

Improvement of chronic diarrhoea in patients with advanced HIV-1 infection during potent antiretroviral therapy

Background:A substantial number of patients with advanced HIV infection suffer from intractable diarrhoea. The aim of this study was to evaluate whether potent antiretroviral therapy could alleviate such diarrhoea. Methods:In an open randomized study the effect of the HIV protease inhibitor indinavir in combination with nucleoside analogue reverse transcriptase inhibitors on chronic HIV-related diarrhoea was investigated in 14 late-stage (CD4+ lymphocyte count ≤ 50 × 106 cells/l) HIV-infected patients. Data concerning stool frequency, stool consistency and antidiarrhoeal drug use were collected in daily diaries over a 24-week period. Endpoints of the study were reduction of stool frequency, improvement of stool consistency, weight gain, and in case of diarrhoea due to Enterocytozoon bieneusi or Cryptosporidium sp. disappearance of these parasites from stool. Results:Thirteen patients started the study drug indinavir. One patient died after 1 week and one patient withdrew prematurely after 18 weeks. Median stool frequency declined from 5.8 daily at baseline to 2.3 daily after 24 weeks (P = 0.04). Stool consistency improved considerably over the study period: before treatment 56% of stools were watery and 0% were formed; at week 24 these figures were 0 and 35%, respectively. Body weight increased significantly with a median increment of 6.6 kg at week 24 (P = 0.0006). In two out of six patients with microsporidiosis and both patients with cryptosporidiosis, stools were free of parasites at week 24. Five out of six patients who used non-specific antidiarrhoeal medication on a regular basis prior to the study had ceased to do so at the end. Conclusion:The use of potent antiretroviral therapy in patients with advanced HIV infection can improve chronic HIV-related diarrhoea and in some cases lead to disappearance of E. bieneusi and Cryptosporidium sp. from the stools.

Local activation of coagulation and inhibition of fibrinolysis in the lung during ventilator associated pneumonia

Background: Fibrin deposition is a hallmark of pneumonia. To determine the kinetics of alterations in local coagulation and fibrinolysis in relation to ventilator associated pneumonia (VAP), a single centre prospective study of serial changes in pulmonary and systemic thrombin generation and fibrinolytic activity was conducted in patients at risk for VAP. Methods: Non-directed bronchial lavage (NBL) was performed on alternate days in patients expected to require mechanical ventilation for more than 5 days. A total of 28 patients were studied, nine of whom developed VAP. Results: In patients who developed VAP a significant increase in thrombin generation was observed in the airways, as reflected by a rise in the levels of thrombin-antithrombin complexes in NBL fluid accompanied by increases in soluble tissue factor and factor VIIa concentrations. The diagnosis of VAP was preceded by a decrease in fibrinolytic activity in NBL fluid. Indeed, before VAP was diagnosed clinically, plasminogen activator activity levels in NBL fluid gradually declined, which appeared to be caused by a sharp increase in NBL fluid levels of plasminogen activator inhibitor 1. Conclusion: VAP is characterised by a shift in the local haemostatic balance to the procoagulant side, which precedes the clinical diagnosis of VAP.

The effect of plasma drug concentrations on HIV-1 clearance rate during quadruple drug therapy

Objective:To investigate the relationship between exposure to antiretroviral drugs and the initial decline of plasma HIV-1 RNA. Design:Open-label study in antiretroviral-naive HIV-1 infected patients using a quadruple drug regimen [nelfinavir (NFV), saquinavir (SQV), stavudine, and lamivudine]. Methods:The elimination rate constant (k) for HIV-1 clearance was calculated during the first 2 weeks of treatment in 29 patients. Exposure to NFV and SQV was quantified on each study visit. Observed NFV and SQV concentrations were related to those expected in a reference population and a concentration ratio was calculated. The median concentration ratios for NFV and SQV, the baseline CD4+ lymphocyte count and baseline log10 HIV-1 RNA were correlated with k. Results:A significant positive correlation was observed between k and the median NFV (P = 0.001) or SQV concentration ratio (P = 0.016) in univariate analysis. In multivariate analyses, the median NFV concentration ratio remained significantly correlated with k. Conclusions:The variation in the rate of decline of plasma HIV-1 RNA between patients after the initiation of a quadruple drug regimen could be explained by differences in exposure to NFV or SQV. Determination of k could be used to optimise further antiretroviral drug therapy and may be a first tool to assess antiretroviral activities of new or increasing doses of drugs administered in combination regimens. Furthermore, our data suggest that exposure to antiretroviral drugs should be incorporated in mathematical models to describe HIV-1 dynamics in more detail.

HIV-1 viral load, phenotype, and resistance in a subset of drug-naive participants from the Delta trial

BACKGROUNDnThe Delta trial showed that combination therapy (zidovudine plus didanosine and zidovudine plus zalcitabine) substantially lengthened life and reduced disease progression compared with zidovudine monotherapy. We did a nested virological study in three countries (France, the Netherlands, and the UK) to investigate changes in markers for viral load and antiretroviral-drug resistance during therapy.nnnMETHODSn240 zidovudine-naive HIV-1-infected patients were randomly assigned zidovudine only (n = 87), zidovudine plus didanosine (n = 80), or zidovudine plus zalcitabine (n = 73). Viral load in peripheral-blood mononuclear cells and plasma was measured by quantitative culture. Plasma HIV-1 RNA was measured by reverse-transcriptase PCR amplification, and serum p24 antigen by ELISA. Resistance to antiretroviral drugs was measured phenotypically by culture and genotypically by detection and quantification of drug-related point mutations in the pol gene. Analyses were done by intention to treat.nnnFINDINGSnThe reduction in viral load was greatest 4-12 weeks after the start of therapy and was most pronounced in the combination-therapy study groups (median reductions of RNA at 4 weeks 1.58, 1.28, and 0.49 log10 copies/mL for zidovudine plus didanosine, zidovudine plus zalcitabine, and zidovudine only, respectively). RNA levels at 8 weeks were predictive of disease progression and death after allowance for baseline values. At 48 weeks, the proportion of participants with phenotypic zidovudine resistance was similar in all three groups: didanosine and zalcitabine resistance were rare; zidovudine genomic resistance correlated with phenotypic resistance (r = 0.54, p < 0.0001) and developed earlier in the combined-therapy groups. However, participants in the zidovudine monotherapy group had higher circulating loads of resistant virus than those in the combined-therapy groups.nnnINTERPRETATIONnCombined antiretroviral therapy was more efficient at lowering virus load than monotherapy. Although zidovudine resistance was common in monotherapy and combined-therapy groups, circulating concentrations of resistant virus were substantially lower in the combination groups, which is likely to be a result of the continued antiviral activity of didanosine or zalcitabine.

Is there a difference in the efficacy of peripartum antiretroviral regimens in reducing mother-to-child transmission of HIV in Africa?

Background:Peripartum antiretroviral regimens have been shown to prevent mother-to-child transmission of HIV (MTCT) in randomized clinical trials; however, direct comparison of published results is impossible given methodological and population differences. Objective:To directly compare the efficacy of different antiretroviral regimens in reducing the risk of 6-week MTCT rate in African breastfeeding populations. Methods:Pooled analysis including all mother–infant pairs from any relevant trial: West African ZDV-placebo trials, Petra ZDV+3TC [two regimens A (pre/intra/post-partum) and B (intra/post-partum), placebo from Uganda and Tanzania], SAINT (NVP and Petra arm B), HIVNET012 (NVP, ultra short ZDV pp) and the Vitamin A trial (as placebo arm in South Africa). Peripartum HIV infection was any positive RNA or DNA polymerase chain reaction test < day 60. The MTCT risk was estimated at 6 weeks for each treatment arm and compared with placebo or single-dose NVP using logistic regression adjusting for maternal CD4 cell count, breastfeeding and birthweight. Results:Overall, 4125 singleton live-births were included; 3629 (88%) were assessed for HIV status at 6 weeks of age. In comparison with placebo, zidovudine + lamivudine (ZDV+3TC) arm A [adjusted odds ratio (AOR), 0.23; P < 0.0001], ZDV+3TC arm B (AOR, 0.49; P < 0.001), antenatal ZDV short (AOR, 0.55; P = 0.006) and nevirapine (NVP) (AOR, 0.60; P = 0.0007) significantly reduced MTCT. In comparison with NVP, only the longest regimen of ZDV+3TC (AOR, 0.39, P < 0.0005) was significantly more effective. Conclusion:These results are in line with current World Health Organisation guidelines suggesting equivalence of choice between single-dose NVP and short-course ZDV, and confirm the greater efficacy of ZDV+3TC than with any single antiretroviral drug.

Determinants of recurrent toxicity-driven switches of highly active antiretroviral therapy. The ATHENA cohort

Background Toxicity is the most important reason for premature switching of highly active antiretroviral therapy (HAART). In order to optimize the benefit–risk ratio of HAART, guidelines for toxicity management are needed. Objective An observational cohort study to estimate the incidence and identify determinants of toxicity-driven switches on second-line HAART after having switched first-line HAART despite successful viral suppression. Methods Patients were selected from those in the ATHENA cohort (n = 2470) who switched the initial HIV protease inhibitor (PI)-containing HAART while plasma HIV-1 RNA was ⩽ 500 copies/ml (n = 775). One-year cumulative incidences of subsequent toxicity-driven switches and adjusted relative risks (RR) for potential determinants were calculated. Results The 1-year cumulative incidence of toxicity-driven switches of the second regimen was 24% [95% confidence interval (CI), 21–28], mostly because of gastrointestinal toxicity and neuropathy. Those who had switched from first HAART because of toxicity were at an increased risk of a recurrent toxicity-driven switch (RR, 2.5; 95% CI, 1.7–3.5). Switching from PI to nevirapine while continuing the other antiretroviral drugs was more protective against a subsequent switch because of further toxicity than changing to another PI-containing regimen (RR, 0.2; 95% CI, 0.1–0.6). Conclusions As for first-line HAART, toxicity is responsible for the majority of switches during second-line HAART. Prior switching for toxicity increased the risk of having to switch the subsequent regimen for toxicity, but this risk is reduced when switching to nevirapine rather than to an alternative PI. The latter should be taken into account when designing toxicity-management guidelines.

High-dose nevirapine in previously untreated human immunodeficiency virus type 1-infected persons does not result in sustained suppression of viral replication

High-dose nevirapine treatment has been reported to confer sustained antiretroviral effects, despite a rapid development of resistance. The use of this strategy was evaluated in 20 previously untreated human immunodeficiency virus type 1 (HIV-1) p24 antigenemic persons with CD4 cell counts between 100 and 500/mm3. Treatment consisted of 400 mg of nevirapine, after a 2-week lead-in dose of 200 mg. Rash was the most frequently reported adverse event, occurring in 25%. While sustained declines in p24 antigen levels were observed in the majority, serum HIV-1 RNA load and CD4 cell counts returned to baseline values within 12 weeks in virtually all subjects. The resistance-conferring tyrosine-to-cysteine substitution at reverse transcriptase position 181 was detected after 4 weeks in most subjects. These observations suggest that plasma drug levels attained with high-dose nevirapine were not sufficient to inhibit nevirapine-resistant virus, although they were approximately 2-fold higher than reported IC50 values of resistant virus.

A randomized, dose-finding study with didanosine plus stavudine versus didanosine alone in antiviral-naive, HIV-infected Thai patients.

ObjectivesTo evaluate the safety and efficacy of four different regimens of didanosine (ddI)u2004+u2004stavudine (d4T) in HIV-infected Thais. DesignProspective, open-label, randomized study. MethodsPatients were randomized to four regimens of high and low doses of ddI and d4T or to ddI alone. D4T was added to the ddI-alone arm after week 24. The duration of study was 48 weeks. ResultsSeventy-eight patients were randomized (mean CD4 cell count, 255u2004×u2004106/l; mean plasma HIV-1 RNA; 4.3 log10 copies/ml). In the intent-to-treat analysis, 78% of patients in the pooled combination arms and 20% of the patients in the ddI alone arm (to which d4T was added after 24 weeks) showed plasma HIV-1 RNA <u2004500u2004copies/ml at week 24 (P u2004<u20040.001), and 59% versus 53% at week 48, respectively. In addition, the proportion of patients with <u200450 HIV-1 RNA copies/ml was 13% versus 7% at week 24 (P u2004=u20040.5) and 17% versus 20% at week 48 respectively. At week 24, median CD4 cell count increases from baseline were 101u2004×u2004106/l in the pooled combination versus 76u2004×u2004106/l in the ddI alone arm (P u2004=u20040.78). Logistic regression modeling suggested a correlation between receiving high dose ddI and achieving HIV-1 RNA <u2004500u2004copies/ml at week 48 (P u2004=u20040.07). ConclusionsThe d4T/ddI combination was superior to ddI alone in producing HIV-1 viral suppression. At week 48, >u200460% of patients treated with this combination reached HIV-1 RNA levels <u2004500u2004copies/ml. Receiving high dose ddI but not d4T may correlate with a better viral suppression.

Cerebrospinal fluid β2-microglobulin, monocyte chemotactic protein-1, and soluble tumour necrosis factor α receptors before and after treatment with lamivudine plus zidovudine or stavudine

CSF levels of beta2-microglobulin (b2m), monocyte chemotactic protein-1 (MCP-1), soluble tumor necrosis factor receptors (sTNFRs), and HIV-1 RNA were determined in 16 neurologically asymptomatic HIV-1 infected patients before and 12 weeks after treatment with lamivudine plus zidovudine or stavudine. b2m levels were significantly higher in patients (1.7 mg/l) compared with controls (0.8 mg/l) (P < 0.001), and decreased to 1.1 mg/l during treatment (P = 0.001). MCP-1 levels were low, and did not change during treatment. Levels of sTNFR type I were elevated in patients (0.92 ng/ml) compared to controls (0.30 ng/ml) (P = 0.03), but did not change during treatment. Levels of sTNFR type II were below the limit of detection in most patients and controls. In conclusion, CSF levels of b2m and HIV-I RNA, but not sTNFRs or MCP-1, are candidate surrogate markers of treatment efficacy in early CNS infection.

Soluble tumor necrosis factor receptors as surrogate markers for the assessment of zidovudine treatment in asymptomatic HIV-1 infection

In untreated, asymptomatic human immunodeficiency virus type 1 (HIV-1) infection, elevated serum concentrations of soluble receptors for tumor necrosis factor (sTNFR) types I and II are associated with progression to AIDS. To assess the utility of sTNFRs as markers for the assessment of antiretroviral treatment, sTNFRs were sequentially determined in 47 asymptomatic HIV-1-infected men, who participated in a double-blind, randomized, placebo-controlled study. Progression to AIDS or severe AIDS-related complex occurred in six zidovudine (ZDV)- and six placebo-treated subjects. During ZDV treatment (n = 28) both types of sTNFRs declined compared with baseline and placebo, whereas they increased during placebo treatment (n = 19). A sustained decline of sTNFRs occurred only in subjects who experienced no disease progression. During the first 3 months of ZDV treatment, the hazard ratio for disease progression when sTNFR type II rose above the baseline value plus 5% was significantly increased (hazard ratio: approximately 25; 95% confidence interval: approximately 1.5-400; p < 0.03). Simultaneously determined CD4+ counts and serum neopterin levels showed a similar pattern in progressors and nonprogressors. Thus, in contrast to CD4+ counts and neopterin levels, sTNFR concentrations, especially those of the type II STNFR, appear to be valuable surrogate markers for monitoring the efficacy of ZDV treatment in asymptomatic HIV-1 infection.