Anti-HBV DNA vaccination does not prevent relapse after discontinuation of analogues in the treatment of chronic hepatitis B: a randomised trial--ANRS HB02 VAC-ADN

OBJECTIVE

The antiviral efficacy of nucleos(t)ide analogues whose main limitation is relapse after discontinuation requires long-term therapy. To overcome the risk of relapse and virological breakthrough during long-term therapy, we performed a phase I/II, open, prospective, multicentre trial using a HBV envelope-expressing DNA vaccine.

DESIGN

70 patients treated effectively with nucleos(t)ide analogues for a median of 3 years (HBV DNA <12 IU/mL for at least 12 months) were randomised into two groups: one received five intramuscular injections of vaccine (weeks 0, 8, 16, 40 and 44) and one did not receive the vaccine. Analogues were stopped after an additional 48 weeks of treatment in patients who maintained HBV DNA <12 IU/mL with no clinical progression and monthly HBV DNA for 6 months. The primary endpoint was defined as viral reactivation at week 72 (HBV DNA >120 IU/mL) or impossibility of stopping treatment at week 48.

RESULTS

Reactivation occurred in 97% of each group after a median 28 days without liver failure but with an HBV DNA <2000 IU/mL in 33%; 99% of adverse reactions were mild to moderate. Immune responses were evaluated by enzyme-linked immunosorbent spot and proliferation assays: there was no difference in the percentage of patients with interferon-γ secreting cells and a specific T-cell proliferation to HBcAg but not to HBsAg after reactivation in each group.

CONCLUSIONS

Although it is fairly well tolerated, the HBV DNA vaccine does not decrease the risk of relapse in HBV-treated patients or the rate of virological breakthrough, and does not restore the anti-HBV immune response despite effective viral suppression by analogues.

TRIAL REGISTRATION NUMBER

NCT00536627.

Archived HIV-1 DNA resistance mutations to rilpivirine and etravirine in successfully treated HIV-1-infected individuals pre-exposed to efavirenz or nevirapine

OBJECTIVES

Efavirenz and nevirapine failure is associated with a rapid selection of resistance-associated mutations (RAMs), which may impact on etravirine or rilpivirine susceptibility. However, RAMs for rilpivirine and etravirine cannot be reported on previous resistance genotypes because these specific RAMs were not analyzed at that time. Therefore, our objective was to determine, in virologically suppressed HIV-1-infected individuals, the presence of RAMs to rilpivirine, etravirine and the combination of tenofovir/emtricitabine/rilpivirine in HIV-1 DNA from individuals previously exposed to efavirenz and/or nevirapine.

METHODS

The studied population included 169 treatment-experienced individuals enrolled in the ANRS 138-EASIER trial who previously failed on and/or were intolerant to efavirenz and/or nevirapine and who had plasma HIV-1 RNA<400 copies/mL. Resistance to rilpivirine, etravirine, tenofovir and emtricitabine by bulk sequencing was performed on extracted HIV-1 DNA from whole blood collected at the time of trial inclusion.

RESULTS

Reverse transcriptase gene amplification was successful in 128/169 (76%) individuals and 95% of HIV-1 were infected with subtype B. Rilpivirine RAMs were detected in 41 (32%) individuals, with highest frequency for the mutations Y181C/I/V (18%), K101E/P (7%) and E138A/G/K/Q/R/S (6%) and the association L100I+K103N/S (5%). Etravirine RAMs were detected in five (4%) individuals. Resistance to emtricitabine, tenofovir and at least one drug included in the combination of tenofovir/emtricitabine/rilpivirine were detected in 72 (56%), 12 (9%) and 88 (69%), respectively.

CONCLUSIONS

In individuals with suppressed viraemia under antiretroviral therapy (ART), but who had been previously exposed to an efavirenz and/or nevirapine-based regimen, rilpivirine RAMs are frequent and etravirine RAMs are rare. This finding suggests that the switch to a rilpivirine-based regimen should not be recommended.

Comparison of resistance mutation patterns in historical plasma HIV RNA genotypes with those in current proviral HIV DNA genotypes among extensively treated patients with suppressed replication

OBJECTIVES

Heavily treatment-experienced patients with good virological control could be at risk of virological failure on switching to a new regimen if pre-existing drug resistance is not taken into account. We examined whether genotyping based on cellular HIV-1 DNA during controlled viraemia identifies resistance mutations detected in plasma HIV-1 RNA during treatment with previous antiretroviral regimens.

PATIENTS AND METHODS

All 169 patients enrolled in the Agence Nationale de Recherche sur le SIDA (ANRS) 138-intEgrase inhibitor MK_0518 to Avoid Subcutaneous Injections of EnfuviRtide (EASIER) trial had already received three antiretroviral drug classes [nucleoside reverse transcriptase inhibitor (NRTI), nonnucleoside reverse transcriptase inhibitor (NNRTI) and protease inhibitor (PI)] and had plasma HIV-1 RNA<400 copies/ml at baseline. The results of previous resistance genotyping of plasma HIV-1 RNA in individual patients were compared with those of resistance genotyping of whole-blood HIV-1 DNA at randomization.

RESULTS

A median of 4 plasma RNA genotypes were available for the 169 patients. The median numbers of resistance mutations in HIV-1 RNA and DNA were, respectively, 5 and 4 for NRTIs, 2 and 1 for NNRTIs, and 10 and 8 for PIs. The difference was significant for all three drug classes (P=0.001). Resistance to at least one antiretroviral drug was detected exclusively in HIV-1 RNA or in DNA in 63% and 13% of patients for NRTI, 47% and 1% of patients for NNRTI, and 50% and 7% of patients for PI, respectively.

CONCLUSION

This study shows that, among highly treatment-experienced patients on effective highly active antiretroviral therapy, resistance genotyping of HIV-1 DNA detects fewer resistance mutations than previous analyses of HIV-1 RNA. These results have implications for patient management and for the design of switch studies.

Virological and immunological outcomes at 3 years after starting antiretroviral therapy with regimens containing non-nucleoside reverse transcriptase inhibitor, protease inhibitor, or both in INITIO: open-label randomised trial

BACKGROUND

Antiretroviral therapy has greatly reduced HIV mortality and morbidity. However, the best sequence of regimens and implications of initial regimen for long-term therapeutic success are not well defined.

METHODS

In INITIO, a large international randomised trial, we compared antiretroviral therapy with two nucleoside analogue reverse transcriptase inhibitors (didanosine+stavudine) plus either a non-nucleoside reverse transcriptase inhibitor (efavirenz, EFV) or a protease inhibitor (nelfinavir, NFV), or both (EFV/NFV), in patients with HIV-1 infection who had not previously received antiretroviral drugs. Primary outcomes were proportion with undetectable HIV RNA in plasma, and change in CD4 count from baseline at 3 years. Analyses were by intention-to-treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN44582462.

FINDINGS

We followed up 911 participants (297 EFV, 311 NFV, 303 EFV/NFV). At 3 years, the proportion with HIV RNA less than 50 copies per mL was highest in the EFV group (188 [74%] EFV, 162 [62%] NFV, 155 [62%] EFV/NFV; p=0.004). Mean (95% CI) increases in CD4 count were 316x10(6) cells per L (288-343) for EFV, 289x10(6) cells per L (262-316) for NFV, and 274x10(6) cells per L (231-291) for EFV/NFV (p=0.1). Fewer participants in the EFV group than in the other groups stopped adequate antiretroviral therapy for more than 30 days (p=0.005). Participants in the EFV/NFV group had shorter time to stopping the initial regimen (p<0.0001) and to a treatment modifying adverse event (p=0.04) than those in the other groups.

INTERPRETATION

Starting antiretroviral therapy with a three-drug/two-class regimen including efavirenz was better than starting with regimens including nelfinavir or efavirenz plus nelfinavir in terms of virological suppression and durability of the initial regimen. The shorter time on adequate antiretroviral therapy or to a treatment-modifying adverse event might explain the absence of additional benefit for the four-drug regimen.

Adverse reactions to cotrimoxazole in HIV-infected patients: predictive factors and subsequent HIV disease progression

The relationship between the onset of adverse events to cotrimoxazole in HIV-infected patients and the subsequent development of toxoplasmosis, other AIDS-defining events and survival was studied in 592 French patients who first received cotrimoxazole during the Delta trial. Low CD4+ cell count at cotrimoxazole introduction was the only factor associated with the onset of adverse reactions. The occurrence of toxoplasmosis and first AIDS-defining events were significantly and independently linked to a low CD4+ cell count at cotrimoxazole introduction (p < 0.0001) and to previous cotrimoxazole withdrawal for adverse events (p = 0.004 and p < 0.0001, respectively), but not to previous cotrimoxazole withdrawal for reasons other than adverse events, as compared to patients who did not discontinue taking cotrimoxazole during this survey. The survival rate was significantly shorter among both patients who stopped taking cotrimoxazole for adverse events and for other reasons (p = 0.03 and p = 0.0001, respectively), as compared to patients who continued to take cotrimoxazole.

CD4 T cell recovery is slower in patients experiencing viral load rebounds during HAART

To determine whether viral load rebounds during HAART impact on CD4+ T cell recovery and immune reconstitution, we studied a prospective cohort of 355 antiretroviral naive patients enrolled to be randomized in a trial of three strategies of induction/maintenance HAART. The extent of immune reconstitution in blood through 72 weeks of antiretroviral treatment was evaluated. Lymphocyte subset markers (CD4, CD8, CD45RA, CD62L, CD16, CD19), activation markers (HLA-DR, CD38, CD25) were performed by cytometry analysis. Our results showed that plasma HIV-1 RNA was suppressed to below 500 copies per ml through week 72 in 240 patients (group 1) while the remaining 115 patients experienced at least one viral rebound (group 2). At baseline, CD4 cell count was higher and HIV-1 RNA was lower in group 1 than in group 2. Over 72 weeks, mean increase in CD4+ T cell count was 0.32 cell/mm3/day in group 1 and only 0.14 cell/mm3/day in group 2 (P < 0.0001). However, the patterns of changes in CD4+ and CD8+ T cell subsets during therapy were very similar across the two groups with only subtle and very limited differences. We conclude that permanent control of HIV replication could be necessary for faster immune reconstitution.

[Clinical trials: principles of the method]

Comparative judgement, which is seminal to any kind of science performing measurements, has been applied to clinical reasoning for many centuries. The need for systematizing the observational methods used in medicine in order to draw more reliable inferences about the effects of therapies has been active all along the 19th century. This has resulted in controlled studies which yielded important advances in clinical and therapeutic knowledge, although their designs were not fully satisfactory. Clinical trials have gained their status of "hard science", methodology allowing causal inference, by the end of the 1940s after having adopted the statistical theories developed in the 1930s by Fisher for experimental design in agronomy. A long way has been run since the first controlled randomized trial. However, half a century later, modern clinical trial remains essentially a controlled randomized prospective study using methods to limit potential biases and to establish statistical significance.

Zidovudine resensitization and dual HIV-1 resistance to zidovudine and lamivudine in the delta lamivudine roll-over study

OBJECTIVE

To study zidovudine resensitization and dual resistance to zidovudine/lamivudine in HIV-1 isolates from nucleoside reverse transcriptase (RT) inhibitor-experienced patients during selective pressure exerted by zidovudine/lamivudine combination therapy.

DESIGN AND METHODS

HIV-1 isolates from 29 patients receiving zidovudine/lamivudine combination therapy in the Delta roll-over study were analysed at entry and during a 1 year follow-up period for phenotypic susceptibility to zidovudine and lamivudine in the ANRS PBMC assay. The RT gene from codon 20 to 230 and at codon 333 was analysed by nucleotide sequencing of the corresponding isolates.

RESULTS

HIV-1 isolates from 23 of the 29 patients were phenotypically resistant to zidovudine at baseline; 61% of these patients showed significant zidovudine resensitization during follow-up. The zidovudine IC50 value correlated positively with log10 plasma HIV-1 RNA (P = 0.02) and negatively with the CD4 cell count (P = 0.004). Zidovudine resensitization (related to acquisition of the M184V mutation) was transient, with evolution towards dual resistance to zidovudine and lamivudine in 20 of the 29 patients. The phenotype of certain dually resistant isolates coincided with the emergence of multiple mutations in the 5' part of the RT gene.

CONCLUSIONS

M184V-mediated zidovudine resensitization of HIV-1 is transient in most patients who are given zidovudine/lamivudine combination therapy when zidovudine resistance has already emerged. The subsequent evolution towards dual phenotypic resistance to zidovudine/lamivudine corresponds to complex genotypic profiles.

Mechanisms of virologic failure in previously untreated HIV-infected patients from a trial of induction-maintenance therapy. Trilège (Agence Nationale de Recherches sur le SIDA 072) Study Team)

CONTEXT

In the Trilège trial, following induction with a zidovudine, lamivudine, and indinavir regimen, human immunodeficiency virus (HIV) replication was less suppressed by 2-drug maintenance therapy than by triple-drug therapy.

OBJECTIVE

To identify mechanisms of virologic failure in the 3 arms of the Trilège trial.

DESIGN

Case-control study conducted from February to October 1998.

SETTING

Three urban hospitals in Paris, France.

PATIENTS

Fifty-eight case patients with virologic failure (HIV RNA rebound to >500 copies/mL in 2 consecutive samples) randomized to 3 therapy groups: triple drug (zidovudine, lamivudine, and indinavir), 8; zidovudine-lamivudine, 29; and zidovudine-indinavir, 21; the case patients were randomly matched with 58 control patients with sustained viral suppression.

MAIN OUTCOME MEASURES

At virologic failure (S1 sample) and 6 weeks later (S2 sample), assessment of protease and reverse transcriptase gene mutations, plasma indinavir level, and degree of viral load rebound; pill count during induction and maintenance periods.

RESULTS

Only 1 primary resistance mutation, M184V, was detected in S1 plasma samples from 4 of 6 patients in the triple-drug and in all 22 in the zidovudine-lamivudine therapy groups and in S2 plasma samples from 3 of 6 in the triple-drug and 20 of 21 in the zidovudine-lamivudine groups. Of controls, M184V was detected in 11 of 13 S1 plasma samples and in 10 of 11 S2 plasma samples. Indinavir levels were undetectable in all S1 samples but 2 in 7 triple-drug cases tested and in the expected range in 11 of 18 S1 and 5 of 12 S2 zidovudine-indinavir case plasma samples tested. Maintenance adherence rates were lower for cases vs controls for zidovudine (P = .05) and indinavir (P = .05). Low indinavir levels, lower adherence rates for zidovudine (P = .04) and lamivudine (P = .03), and rebound to near-baseline values suggested adherence as cause of early failure for 4 of 8 triple-drug cases. In the zidovudine-lamivudine arm, for which case and control adherence rates did not differ significantly (P = .96), most failures occurred late with low rebound, suggesting suboptimal drug potency. In the zidovudine-indinavir arm, virologic failures may be related to both mechanisms.

CONCLUSIONS

During the maintenance phase early and late virologic failures appeared to be related more to problems of adherence and antiretroviral treatment potency, respectively, than to selection of resistant mutant viruses.

Comparison of subcutaneous and intravenous interleukin-2 in asymptomatic HIV-1 infection: a randomised controlled trial. ANRS 048 study group

BACKGROUND

Intermittent interleukin-2 therapy for HIV-1 by continuous intravenous infusion leads to sustained increase of CD4 T cells. This method of administration is, however, inconvenient and has limiting toxic effects. We did a randomised study to compare safety and efficacy of antiviral treatment alone or combined with various interleukin-2 regimens in HIV-1-infected patients.

METHODS

94 symptom-free patients, naïve to antiretroviral treatment, with CD4-T-cell counts of 250-550 cells/microL at baseline were randomly assigned zidovudine and didanosine alone (n=26) or combined with interleukin-2 administered intravenously (12 million IU/day, n=22) or subcutaneously (3 million IU/m2 twice daily, n=24) for 5 days, or were given polyethylene-glycol-modified (PEG) interleukin-2 (2 million IU/m2 intravenous bolus, n=22) administered every 2 months from week 2 to week 50 (seven cycles). Safety and immunological and virological results were monitored until week 56.

FINDINGS

CD4-T-cell count increased to higher than baseline by a mean of 564 cells/microL (subcutaneous group), 676 cells/microL (intravenous group), 105 cells/microL (PEG group), and 55 cells/microL (antiretroviral-therapy group, p=0.0001). 68% and 77% of patients in the subcutaneous and intravenous groups, respectively, achieved an 80% increase of CD4 T cells (p<0.001). In these two groups, 50% of patients restored a CD4/CD8-T-cell ratio of more than 1. The groups did not differ significantly for changes in plasma HIV-1 RNA loads throughout the study. The duration of common side-effects of interleukin-2 was shorter in the subcutaneous group, which enabled outpatient treatment. Naïve and memory CD4 T cells, CD28 expression on CD4 and CD8 T cells, and restoration of in-vitro proliferative response to mitogens and recall antigens increased in the intravenous and subcutaneous groups.

INTERPRETATION

Subcutaneous interleukin-2 is a convenient regimen that, as well as intravenous therapy, improves immunological function in HIV-1-infected patients receiving two nucleosides. Larger studies are needed to show whether immunological improvements translate into clinical benefit.

Specific anti-toxoplasmic IgG antibody immunoblot profiles in patients with AIDS-associated Toxoplasma encephalitis

Among 186 suspected cases of Toxoplasma encephalitis (TE) in HIV-infected patients, 113 were classified as TE and 73 as non-TE. Serum Toxoplasma gondii (T.g.) antibodies were detected by ELISA in 97% of TE vs 71% of non-TE cases (p < 0.001). In the 164 patients positive for T. g. antibodies, the IgG 27 and 32 bands were more frequently present in TE than in non-TE (p = 0.003, p = 0.002, respectively). Among patients with positive T.g. serology, multivariate analysis showed that the presence of an IgG 32 (OR 3.1) or IgG 27 band (OR 2.7) on Western blot was highly indicative of TE independently of each other. Positive T.g. serology, but not anti-T.g. IgG antibody titres, was predictive. Thus, the positivity of IgG 27 and 32 bands on Western blot analysis provides useful data for improving the diagnosis of presumptive TE in HIV-infected patients with suspected TE and positive Toxoplasma serology.

Effect of a 14-day course of foscarnet on cytomegalovirus (CMV) blood markers in a randomized study of human immunodeficiency virus-infected patients with persistent CMV viremia. Agence National de Recherche du SIDA 023 Study Group

A randomized open-label phase 2 trial compared the virological and clinical effects on cytomegalovirus (CMV) infection of a 14-day course of intravenous foscarnet (100 mg/[kg x 12 h]) or no treatment in 42 HIV-infected patients with < 100 CD4 cells/mm3 and persistent asymptomatic CMV viremia. All CMV markers (blood culture, pp65 antigenemia, plasma and leukocyte DNA) either became negative or decreased significantly at day 14 in the foscarnet group. CMV blood culture results at day 14 were positive in 14% of those receiving foscarnet versus 60% of control patients (P = .004). However, after the end of treatment, all markers reappeared or the virus load rapidly increased. The probability of CMV disease at 6 months was 43% in both groups. Patients who had or who achieved a negative blood culture at any time had a reduced risk of CMV disease (RR = 2.64; 95% CI = 1.24-5.62; P = .02). This study suggests that sequential courses of intravenous foscarnet might not be a good strategy for preemptive therapy in this population and that in patients with a positive blood marker, treatment able to induce and maintain negative CMV blood cultures could constitute an effective intervention.

Zidovudine Resensitization and Dual HIV-1 Resistance to Zidovudine and Lamivudine in the Delta Lamivudine Roll-Over Study

Objective

To study zidovudine resensitization and dual resistance to zidovudine/lamivudine in HIV-1 isolates from nucleoside reverse transcriptase (RT) inhibitor-experienced patients during selective pressure exerted by zidovudine/lamivudine combination therapy.

Design and methods

HIV-1 isolates from 29 patients receiving zidovudine/lamivudine combination therapy in the Delta roll-over study were analysed at entry and during a 1 year follow-up period for phenotypic susceptibility to zidovudine and lamivudine in the ANRS PBMC assay. The RT gene from codon 20 to 230 and at codon 333 was analysed by nucleotide sequencing of the corresponding isolates.

Results

HIV-1 isolates from 23 of the 29 patients were phenotypically resistant to zidovudine at baseline; 61% of these patients showed significant zidovudine resensitization during follow-up. The zidovudine IC50 value correlated positively with log10 plasma HIV-1 RNA ( P=0.02) and negatively with the CD4 cell count ( P=0.004). Zidovudine resensitization (related to acquisition of the M184V mutation) was transient, with evolution towards dual resistance to zidovudine and lamivudine in 20 of the 29 patients. The phenotype of certain dually resistant isolates coincided with the emergence of multiple mutations in the 5’ part of the RT gene.

Conclusions

M184V-mediated zidovudine resensitization of HIV-1 is transient in most patients who are given zidovudine/lamivudine combination therapy when zidovudine resistance has already emerged. The subsequent evolution towards dual phenotypic resistance to zidovudine/lamivudine corresponds to complex genotypic profiles.

A randomized trial of three maintenance regimens given after three months of induction therapy with zidovudine, lamivudine, and indinavir in previously untreated HIV-1-infected patients. Trilège (Agence Nationale de Recherches sur le SIDA 072) Study Team

BACKGROUND

The long-term effectiveness of potent three-drug antiretroviral regimens for the treatment of human immunodeficiency virus type 1 (HIV-1) infection is limited by problems related to compliance and tolerability. We investigated whether two-drug maintenance therapy would suppress viral replication after a three-month period of aggressive triple-drug induction therapy.

METHODS

A total of 378 HIV-1-infected adults who had not received previous antiretroviral treatment received three months of induction therapy consisting of 300 mg of zidovudine every 12 hours, 150 mg of lamivudine every 12 hours, and 800 mg of indinavir every 8 hours. The 279 patients in whom the plasma HIV-1 RNA titer fell below 500 copies per milliliter after two months of triple-drug therapy, and who completed the induction phase, were randomly assigned at month 3 to one of the following three open-label maintenance regimens: zidovudine, lamivudine, and indinavir; zidovudine and lamivudine; or zidovudine and indinavir. The primary end point was an increase in HIV-1 RNA levels to 500 copies or more per milliliter during the maintenance phase.

RESULTS

The proportion of patients who reached the primary end point was significantly higher among patients receiving zidovudine plus lamivudine (29 of 93 patients, P<0.001) or zidovudine plus indinavir (21 of 94, P=0.01) than among patients receiving continued triple-drug therapy (8 of 92). This higher failure rate in the groups treated with the two-drug maintenance regimens was also observed in the subgroup of patients with maximally suppressed HIV-1 RNA (below 50 copies per milliliter) at the time of randomization to maintenance therapy.

CONCLUSIONS

In HIV-1-infected adults not previously treated with antiretroviral drugs whose plasma HIV-1 RNA levels fell below 500 copies per milliliter after three months of induction therapy with zidovudine, lamivudine, and indinavir, two-drug maintenance therapy was less effective in sustaining a reduced viral load than continued three-drug therapy.

Intention-to-treat vs. on-treatment analyses of clinical trial data: experience from a study of pyrimethamine in the primary prophylaxis of toxoplasmosis in HIV-infected patients. ANRS 005/ACTG 154 Trial Group

Randomized clinical trials analyzed by the intent-to-treat approach provide unbiased comparisons among treatment groups. To avoid dilution of treatment effect, many people also perform an analysis by treatment actually received, although this method may introduce bias into the results. This paper presents several approaches used for analyzing data of a recent trial and the difficulties encountered in interpreting the results of each approach. The ANRS 005/ACTG 154 Study was a double-blind, placebo-controlled, randomized, international (French, U.S., and Spanish) multicenter trial designed to assess the effectiveness of pyrimethamine for the primary prophylaxis of cerebral toxoplasmosis (CT) in HIV-infected patients with advanced immunodeficiency. In the intention-to-treat analysis, the cumulative probability of CT at 1 year did not differ significantly between the pyrimethamine arm (11.9%) and the placebo arm (13.1%), Hazard Ratio (HR) = 0.94 (95% Confidence Interval (CI) = 0.62-1.42), whereas an on-treatment analysis resulted in a significant difference: 4.2% in the pyrimethamine arm and 12.4% in the placebo arm, HR = 0.44 (95% CI = 0.24-0.80). The data showed a significant interaction between compliance and treatment outcome; and side effects were more frequently cited as reasons for compliance violations in the pyrimethamine group. Several different analytic approaches (censoring data at the time patients discontinued the study medication only for selected reasons) failed to explain the disparity between the estimation of effect of pyrimethamine by the intention-to-treat and on-treatment analyses. This experience led us to believe that comparing the results of both analyses was the best method to convince clinicians that intention-to-treat was the only interpretable analysis. We were concerned that even if pyrimethamine had a beneficial effect, it was very difficult (1) to quantify and (2) to apply to clinical practice unless one could predict the occurrence of study drug discontinuation for each patient at the time of treatment assignment. Although exploratory analyses may yield clinically relevant information and useful clarifications in the evaluation of treatments, intention-to-treat remains the only interpretable analysis of clinical trials.

Discrepant responses to triple combination antiretroviral therapy in advanced HIV disease

OBJECTIVES

To determine the clinical, virological and immunological outcome in a cohort of unselected patients receiving triple combination therapy for more than 1 year.

METHODS

Prospective follow-up of a cohort of 162 unselected, protease inhibitor-naive, antiretroviral-experienced patients with advanced HIV disease, treated with indinavir combined with two nucleoside analogues.

RESULTS

The mean CD4 cell count and plasma HIV RNA level in the study group at baseline were 69+/-5 x 10(6)/l and 4.75+/-0.07 log10 copies/ml, respectively. Five per cent of patients died prematurely or were lost to follow-up. Fifty-seven per cent of patients responded to therapy, as assessed by a sustained increase in CD4 cell counts above 50 x 10(6)/l and a decrease in plasma HIV RNA greater than 1 log10 copies/ml, throughout 12.1 months of follow-up. Seventeen per cent of patients were immunological and virological non-responders. Twenty-one per cent of patients exhibited discrepant virological and immunological responses to treatment, of whom one-half failed to exhibit significant increases in CD4 cells despite a virological response to therapy and one-half exhibited increased CD4 cell counts in the absence of significant decrease in plasma viral load. The incidence of AIDS-defining events in the latter group of patients was similar to that of responder patients, whereas their incidence was higher in patients who failed to exhibit a virological and immunological response and those who failed to increase CD4 cells despite a significant decrease in viral load.

CONCLUSION

Our observations of discrepant immunological and virological responses to treatment raise the issue of the significance of persistent elevated levels of plasma HIV RNA and of the relevance of measurements of plasma viral load for assessing the efficacy of antiretroviral therapy in patients whose CD4 cell counts increase despite the absence of significant decrease in plasma HIV viral load.

A prospective study of criteria for the diagnosis of toxoplasmic encephalitis in 186 AIDS patients. The BIOTOXO Study Group

OBJECTIVE

To define the factors associated with diagnosis of toxoplasmic encephalitis (TE) in AIDS patients; and to establish a rational procedure for the clinician faced with a decision concerning empiric antitoxoplasma therapy.

DESIGN

A 15-month prospective multicentre cohort study in France.

METHODS

One hundred and eighty-six consecutive HIV-positive inpatients undergoing empiric antitoxoplasma therapy for a first episode of presumed TE were monitored. The clinician's initial estimation of the probability of response to antitoxoplasma therapy was recorded. In addition, a validation committee classified cases as TE or non-TE.

RESULTS

Among the 186 patients, the following variables were significantly more frequent in TE (n = 113) than non-TE (n = 73) patients: fever (59% versus 40%). headache (55% versus 33%), seizures (22% versus 11%), suggestive lesions on the brain scan (98% versus 76%), positive Toxoplasma serology (97% versus 71%). Median CD4+ lymphocyte count was significantly higher in TE than in non-TE (27 x 10(6)/l versus 11 x 10(6)/l). The rate of TE in patients on systemic antiprotozoal prophylaxis at entry was 43% as compared with 75% in patients without previous prophylaxis. Pre-therapy estimation of response to empiric therapy was highly correlated with final diagnosis. Multivariate logistic regression analysis showed that the following variables contributed independently to the diagnosis of TE: clinician's estimation of response to treatment at entry > 75%; absence of systemic antiprotozoal prophylaxis; seizures; headache; suggestive lesions on CT or MRI brain scan; and positive Toxoplasma serology.

CONCLUSIONS

A linear logistic model is proposed which uses significant variables, which are readily available. This model gives good accuracy to classify suspected cases of TE.

Randomized comparison of amphotericin B deoxycholate dissolved in dextrose or Intralipid for the treatment of AIDS-associated cryptococcal meningitis

We conducted a randomized, open-labeled clinical trial to compare the tolerability and efficacy of amphotericin B deoxycholate, prepared in 5% dextrose or Intralipid (Kabi Pharmacia, Saint-Quentin-en-Yvelines, France), in the treatment of AIDS-associated cryptococcal meningitis in Burundi. Forty-four patients were assigned to receive amphotericin B/dextrose (0.7 mg/[kg.d]) for 14 days; the dose was then reduced to 1 mg/kg every other day for 28 days (infused over 6 hours). Forty-six patients were assigned to receive Intralipid/amphotericin B at a 50% higher dosage (1 mg/[kg.d]) for 14 days; the dose was then reduced to 1.5 mg/kg every other day for 28 days (infused over 2 hours). Intralipid significantly decreased the incidence of fever (P = .02) and chills (P = .0001) related to the infusion of amphotericin B deoxycholate. Analysis of the time to the onset of increased levels of serum creatinine (creatinine level, > 150 mumol/L) showed that Intralipid/amphotericin B was more nephrotoxic (P = .03). The percentage of patients who were clinically cured or had improvement in their conditions and successful mycological outcome was similar in both therapeutic groups, but analysis of the time to the first negative cerebrospinal fluid culture showed a nearly significant difference that favored Intralipid/amphotericin B (P = .07). Intralipid reduced the infusion-related toxicity of amphotericin B deoxycholate without altering its antifungal efficacy but did not confer substantial benefit against renal toxicity that would allow the unitary dosage of amphotericin B deoxycholate to be increased safely.

Lower survival in AIDS patients receiving dapsone compared with aerosolized pentamidine for secondary prophylaxis of Pneumocystis carinii pneumonia. Study Group

A randomized, unblinded study compared aerosolized pentamidine, 300 mg every month, and dapsone, 50 mg/day, for secondary prophylaxis of pneumocystosis in 196 AIDS patients. The study was prematurely discontinued due to excess mortality in the dapsone group. After a mean follow-up of 13 +/- 6.4 months, 22 (21%) of 103 patients in the pentamidine group were dead compared with 39 (42%) of 93 receiving dapsone; the estimated mortality rates at 18 months were 24.6% and 53.1%, respectively (P < .003, log-rank test). A negative interaction was observed between zidovudine and dapsone (P < .049, interaction test of Cox model), and the mean CD4 cell count during the study was lower in the dapsone (49 +/- 61/mm3) than in the pentamidine group (83 +/- 88/mm3; P < .002, t test). The lower survival might also be related to the oxidative effect of dapsone or to the addition of iron protoxalate to dapsone in this study. These results suggest caution in using dapsone as long-term therapy in advanced human immunodeficiency virus infection, especially in those receiving zidovudine.

[Antiretroviral treatments in human immunodeficiency virus infection]

Antiretroviral drugs already registered or currently in clinical trials are shortly described, including dideoxynucleosides, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, tat inhibitors and antisens molecules. In a second part, the treatment of patients with the nucleosides already on the market or in a pre-registration phase is reviewed, on the basis of an analysis of available phase III clinical trials. The third part describes the strategy of clinical trials and explains why "surrogate markers" including markers of viral replication cannot yet be the main criteria to evaluate the efficacy of a new drug in a phase III trial.

Toxoplasma gondii infection in advanced HIV infection

OBJECTIVE

To study Toxoplasma encephalitis (TE) in advanced HIV infection, including predictive factors, possible prophylactic regimens and impact on survival.

DESIGN

Epidemiological analysis of data collected prospectively during the Alpha study, a double-blind, randomized clinical trial, comparing two doses of dideoxyinosine in patients with advanced HIV disease.

PATIENTS

First episode of TE occurred in 75 out of 499 patients participating in the trial.

METHODS

Kaplan-Meier estimates and semi-parametric Cox's model were used.

RESULTS

A low CD4 cell count and a positive Toxoplasma serology were strongly predictive of the occurrence of TE. In patients with CD4 counts < 100 x 10(6)/l and a positive Toxoplasma serology at entry to the study, the 12-month TE incidence was 25.4%. Patients who were receiving at entry any of the following potentially antitoxoplasmic drugs: trimethoprim-sulphamethoxazole, pyrimethamine, dapsone, pyrimethamine-sulphadoxine or sulphadiazine, had a lower TE incidence than those who were not; 6.2 versus 18.8%, respectively (P < 0.001). The rate of survival 12 months after TE was 29.6%. Even after adjusting the major prognostic covariates, TE was predictive of death (P < 0.001; relative risk, 1.8).

CONCLUSIONS

The high HIV incidence, morbidity and mortality in high-prevalence areas suggests that primary prophylaxis should be given in patients at high risk for toxoplasmic reactivation.

Consistency of routine measurements of CD4+, CD8+ peripheral blood lymphocytes

In order to evaluate the reliability of CD4 and CD8 T lymphocyte counts in large scale studies, a quality control study was performed in 12 French laboratories. CD4 and CD8 counts, assessed by various haematological and immunological techniques, were compared in order to assess possible differences between the laboratories and the techniques used. Our data showed that (a) the consistency of CD4 measurements was satisfactory since the between-laboratory coefficient of variation for absolute CD4 cell numbers above 200/mm3 was around 15% instead of 5-10% for all laboratories but one; (b) the major sources of variability arose from the use of automatic devices in the two-step measurement procedure: immunophenotyping and haematological counting. These data suggest that multicentre assays of CD4 and CD8 counts result in some increase in their variability. Nevertheless the results of large multicentric trials can be extrapolated with confidence in the routine care of HIV+ patients. Together, the results justified the involvement of several experienced laboratories in a clinical trial of HIV-related disease.

[Ecology of leishmaniasis in the south of France. 21. Influence of temperature on the development of Leishmania infantum Nicolle, 1908 in Phlebotomus ariasi Tonnoir, 1921. Experimental study]

The influence of temperature on the life-cycle of Leishmania infantum Nicolle, 1908 (isolated from a dog in the Cévennes) in a known vector (Phlebotomus ariasi Tonnoir, 1921) was studied with special reference to the proportion of flies infected and the intensity and localization of parasites in the sandfly. Wild female sandflies were caught at night by active searches and were put with a heavily infected dog in a mosquito net on the night of capture. On the following morning, engorged females were tubed individually and were then maintained at 10, 15, 20, or 25 degrees C (+/- 1.5 degrees). The temperatures were chosen after preliminary experiments which showed that temperatures of 30 degrees C or less than 5 degrees C were lethal to both the sandfly and, usually, the parasite. Midguts of the flies were dissected and examined 6 to 10 days after the infective feed. Although there were no obvious differences in the proportions of infected sandflies at different temperatures, a statistical analysis of the finding (chi 2 test) showed that raising the temperature: significantly increased the overall proportion of infected sandflies; speeded up the multiplication of promastigotes in the midgut; controlled the movement of parasites forwards into the thoracic midgut (from 15 degrees C); encouraged the attachment of the flagellates to the wall of the stomodaeal valve (from 20 degrees C). The use of an exponential model to deduce the size of the parasite population at the different temperatures led to the conclusion that the optimum temperature for L. infantum is in the region of 25 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)