Are Specific Antiretrovirals associated with an Increased Risk of Discontinuation due to Toxicities or Patient/Physician Choice in patients with Hepatitis C Virus Coinfection?

Background

Liver damage associated with hepatitis C (HCV) may influence the likelihood of experiencing discontinuation due to toxicities or patient/physician choice (TOXPC) in patients taking combination antiretroviral therapy (cART). Little information to address this concern is available from clinical trials as patients with HCV are often excluded.

Aims

To compare incidence rates of discontinuation due to TOXPC associated with specific antiretrovial drugs in patients with or without HCV.

Patients/methods

A total of 4929 patients from EuroSIDA under follow-up from January 1999 on a specific nucleoside pair (zidovudine/lamivudine, didanosine/stavudine, stavudine/lamivudine, or other) with a third drug (abacavir, nelfinavir, indinavir, nevirapine, efavirenz, lopinavir/ ritonavir or other boosted-protease inhibitor (PI)-containing regimen) and with known HCV serostatus were studied for the incidence of discontinuation of any nucleoside pair or third drug due to TOXPC. Incidence rate ratios were derived from Poisson regression models.

Results

In total 1358 patients had HCV (27.5%). During 12 799 person-years of follow-up there were 2141 discontinuations due to TOXPC for nucleoside pairs and 2501 for third drugs. The incidence of discontinuation due to TOXPC was consistently higher in patients with HCV after stratification by nucleoside pair or third drug. After adjustment for CD4+ count, gender, exposure group, time on HAART, region and treatment regimen, there were few differences in the rate of discontinuation due to TOXPC in those with HCV compared with those without for any nucleoside pairs or third drugs. Similar results were seen when concentrating on discontinuation due to toxicities alone.

Conclusions

Although patients with HCV generally had higher rates of discontinuation due to TOXPC compared with patients without HCV, there was little evidence to suggest that this was associated with any specific nucleoside pair or third drug used as part of cART. Our results do not suggest that any specific component of cART is more poorly tolerated in patients with HCV or that the presence of HCV should influence the choice between antiretrovirals used as part of a cART regimen.

Thymidine Analogue Mutation Profiles: Factors Associated with Acquiring Specific Profiles and their Impact on the Virological Response to Therapy

Background

Studies have suggested that HIV-1 may develop thymidine analogue mutations (TAMs) by one of two distinct pathways – the TAM1 pathway (including mutations 41L, 210W and 215Y) or the TAM2 pathway (including mutations 67N, 70R and 219E/Q) – under the pressure of a not fully suppressive thymidine-analogue-containing regimen.

Methods

Frozen plasma samples stored in the EuroSIDA repository were selected and sent to two central laboratories for genotypic analysis. We considered 733 patients with at least one genotypic test showing ≥1 TAMs (the first of these tests in chronological order was used). TAM1 and TAM2 genotypic profiles were defined in accordance with previous literature. Statistical modelling involved logistic regression and linear regression analysis for censored data.

Results

The observed frequencies of patterns classifiable as TAM1 or TAM2 profiles were markedly higher than the probabilities of falling into these classifications by chance alone. The chance of detecting a TAM2 profile increased by 25% per additional year of exposure to zidovudine. We found that mutations 67N and 184V were not associated with a particular TAM profile. In the presence of TAM2 profiles, the adjusted mean difference in the 6-month viral reduction was 0.96 log10 copies/ml (95% confidence interval: 0.20; 1.73) higher in patients who started stavudine-containing regimens instead of zidovudine-containing regimens.

Conclusions

This study provides evidence that the suggested TAM clustering is a real phenomenon and that it may be driven by which thymidine analogue the patients has used. In patients with TAM2-resistant viruses, stavudine appears to retain greater viral activity than zidovudine.

Baseline Resistance and Virological Outcome in Patients with Virological Failure who Start a Regimen Containing Abacavir: Eurosida Study

Objectives

To investigate the ability of several HIV-1 drug-resistance interpretation systems, as well as the number of pre-specified combinations of abacavir-related mutations, to predict virological response to abacavir-containing regimens in antiretroviral therapy-experienced, abacavir-naive patients starting an abacavir-containing regimen in the EuroSIDA cohort.

Patients and methods

A total of 100 HIV-infected patients with viral load (VL) >500 copies/ml who had a plasma sample available at the time of starting abacavir (baseline) were included. Resistance to abacavir was interpreted by using eight different commonly used systems that consisted of rules-based algorithms or tables of mutations. Correlation between baseline abacavir-resistance mutations and month 6 virological response was performed on this population using a multivariable linear regression model accounting for censored data.

Results

The baseline VL was 4.36 log10 RNA copies/ml [interquartile range (IQR): 3.65–4.99 log10 RNA copies/ml] and the median CD4 cell count was 210 cells/μl (IQR: 67–305 cells/μl). Our patients were pre-exposed to a median of seven antiretrovirals (2–12) before starting abacavir therapy. The median (range) number of abacavir mutations (according to the International AIDS Society-USA) detected at baseline was 3.5 (0–8). Overall, the Kaplan–Meier estimate of the median month 6 VL decline was 0.86 log10 RNA copies/ml [95% confidence intervals (95% CI): 0.45–1.24]. The VL in those patients ( n=31) who intensified treatment by adding only abacavir decreased by a median 0.20 log10 RNA copies/ml (95% CI: -0.18; +0.94). The proportion of patients who harboured viruses fully resistant to abacavir among the eight genotypic resistance interpretation algorithms ranged from 12% [Agence Nationale de Recherches sur le SIDA (ANRS)] to 79% [Stanford HIV RT and PR Sequence Database (HIVdb)]. Some interpretation systems showed statistically significant associations between the predicted resistance status and the virological response while others showed no consistent association. The number of active drugs in the regimen was associated with greater virological suppression (additional month 6 VL reduction per additional sensitive drug=0.51, 95% CI: 0.15–0.88, P=0.006); baseline VL was also weakly associated (additional month 6 VL reduction per log10 higher=0.30, 95% CI: -0.02; +0.62, P=0.06). In contrast, the number of drugs previously received was associated with diminished viral reduction (additional month 6 VL reduction per additional drug=-0.14, 95% CI: -0.28; 0.00, P=0.05).

Conclusions

Our results revealed a high degree of variability among several genotypic resistance interpretation algorithms currently in use for abacavir. Therefore, the interpretation of genotypic resistance for predicting response to regimens containing abacavir remains a major challenge.

Response to Antiretroviral Therapy among Patients Exposed to Three Classes of Antiretrovirals: Results from the Eurosida Study

There is an increasing proportion of HIV-positive patients exposed to all licensed classes of antiretrovirals, and the response to salvage regimens may be poor. Among over 8500 patients in EuroSIDA, the proportion of treated patients exposed to nucleosides, protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitor (NNRTI) increased from 0% in 1996 to 47% in 2001. Four-hundred-and-thirteen patients, who had failed virologically two highly active antiretroviral therapy (HAART) regimens and experienced all three main drug classes, started a salvage regimen of at least three drugs, in which at least one new PI or NNRTI was included. Median viral load was 4.7 log copies/ml [Interquartile range (IQR) 4.2–5.2], CD4 lymphocyte count 150/mm3 (IQR 60–274/mm3) and follow-up 14 months. Of these patients, 283 (69%) subsequently experienced at least a 1 log decline in viral load and 202 (49%) achieved a viral load <500 copies/ml. Conversely, the CD4 count halved from the baseline value in 88 (21%), and 45 (11%) experienced a new AIDS-defining disease. In multivariable analyses, a 1 log viral load reduction was related to baseline viral load [relative hazard (RH) 1.27 per 1 log higher; P=0.008], a previous viral load of less than 500 copies/ml (RH 1.69; P=0.002), more recent initiation of the regimen (RH 1.36 per year more recent; P=0.02), number of new drugs in the regimen (RH 1.20 per drug; P=0.02), time since start of antiretroviral therapy (RH 0.94 per extra year; P=0.035) and time spent on HAART with viral load >1000 copies/ml (RH 0.96 per extra month; P=0.0001). Analysis of factors associated with CD4 count decline and new AIDS disease also indicated improved outcomes in more recent times and a tendency for a better response in those starting more new drugs, but no relationship with the total number of drugs. Outcomes in people starting salvage regimens appear to depend on the number of new drugs started but not on the total number of drugs being used.

Kinetics of beta-chemokine levels during anti-HIV therapy

Chemokines are pro-inflammatory cytokines that inhibit human immunodeficiency virus type 1 (HIV-1) replication in vitro. We studied the kinetics of the beta-chemokines, macrophage inhibitory protein (MIP)-1 alpha, MIP-1 beta, RANTES, and monocyte chemotactic protein (MCP)-1 in plasma during 12 months of antiretroviral therapy in 26 HIV-1-infected patients and in 11 untreated subjects. Eleven patients with moderate immunodeficiency had HIV-1 RNA levels < 50 copies/ml after 1 year, whereas 12 out of 15 patients with severe immunodeficiency had detectable virus. At baseline, MCP-1 levels correlated positively with HIV-1 RNA and DNA levels and inversely with CD4 cell counts. A reverse pattern was seen for the MIP-1 beta levels. No correlation was seen between MIP-1 alpha or RANTES and any of the parameters. Also, there was a dichotomy between the different beta-chemokines in response to therapy. Decreases of MCP-1 and RANTES levels were found, but no durable changes of MIP-1 alpha and MIP-1 beta. The MCP-1 levels rebounded back to baseline after 1 year in the patients who responded virologically, which could possibly reflect an increased immune activation. The biological consequences of the changes in beta-chemokines levels during antiretroviral treatment are still unknown and deserve further studies.

Entamoeba gingivalis in human immunodeficiency virus type 1-infected patients with periodontal disease

Necrotic periodontal disease is a progressive painful oral lesion in human immunodeficiency virus type 1 (HIV-1)-infected patients, and the etiology is unknown. Earlier studies of HIV-1-infected patients have shown significant changes in the viral and fungal oral microflora. The aim of this study was to relate the occurrence of protozoa to clinical symptoms and immunosuppression. Oral symptoms were registered in 45 patients at different stages of the HIV-1 infection and in 15 HIV-seronegative healthy controls. Saliva and dental plaque were analyzed for the presence of protozoa. Entamoeba gingivalis was the only protozoa found in the oral cavities of HIV-1-infected patients with periodontal disease. Its presence was not related to the degree of immunodeficiency but to the HIV diagnosis. This study describes for the first time the findings of E. gingivalis in the oral cavities of HIV-1 infected patients.

Longer survival after HIV infection for injecting drug users than for homosexual men: implications for immunology

BACKGROUND

Comparisons of progression in HIV-1 infection between injecting drug users (IDU) and homosexual men have been inconclusive due to the short follow-up periods, often with less well-defined starting points and endpoints. In addition, comparisons of survival after injection have been to some extent obscured by higher non-AIDS mortality in IDU.

METHOD

In a retrospective cohort study, homo-/bisexual men and IDU were followed, with dates of seroconversion defined within +/- 1 year by a previously negative HIV antibody test. Endpoints were CD4 cell count below 200 x 10(6)/l, AIDS and death from AIDS.

RESULTS

Sixty-three homo-/bisexual men and 125 IDU fulfilled the entry criteria, with no significant differences in age at or date for seroconversion. Mean follow-up times were 6.7 and 7.0 years, respectively. The homo-/bisexual group had a significantly accelerated progression rate to all three endpoints: time to CD4 cell count below 200 x 10(6)/l (P = 0.002), to AIDS (P = 0.0003), and to death from AIDS (P < 0.0001). Adjusting for age and sex only made marginal alterations. Ten years after infection, 54% of homosexual men had developed an AIDS-defining condition and 51% had died from AIDS, whereas the corresponding precentages in the IDU group were 26 and 15, respectively. There was, however, no difference in overall mortality due to almost constant, non HIV-related, yearly mortality of some 4% in IDU.

CONCLUSIONS

In our cohort there was a highly significant difference in disease progression and death from AIDS between homo-/bisexual men and IDU. This difference was proposed to be due to the transmission route determining the initial immune response and suggested that this route may have played a more important role than virus variability of the subsequent prognosis.

Epidemiology of AIDS-related Kaposi's sarcoma in Europe over 10 years. AIDS in Europe Study Group

OBJECTIVES

To determine the incidence and risk factors associated with Kaposi's sarcoma (KS) occurrence as an AIDS-defining condition or after the diagnosis of AIDS.

DESIGN

Multicentre retrospective cohort study of AIDS in Europe database from 52 clinical centres in 17 European countries.

METHODS

Patients' charts (n = 6546) were reviewed and collected in the database of the AIDS in Europe Study Group from 1979 to 1989. At the time of AIDS diagnosis 1394 patients had KS, whereas an additional 525 others developed KS after AIDS diagnosis. Univariate analysis and development of multivariate models determined factors associated with KS occurrence.

RESULTS

Frequency of KS as an AIDS-defining condition significantly declined over time (P < 0.0001). In our cohort of patients, homo-/bisexual men from central Europe with CD4 cell counts > 150 x 10(6)/l were statistically more likely to develop KS at the time of AIDS diagnosis (P < 0.0001). For patients with an AIDS diagnosis other than KS, the probability of developing KS during the follow-up was 10 and 24% after 12 and 36 months, respectively. Variables significantly associated with a further KS development were transmission group, central European residence, previous herpes simplex infection other than ulcers, and low CD4 cells (< 150 x 10(6)/l). Previous zidovudine therapy had no influence on KS appearance. For patients who developed KS subsequent to AIDS diagnosis, there was no significant decline of the incidence over the 10-year time period.

CONCLUSIONS

This large cohort study clearly shows that demographic data such as sex, transmission group and region of Europe have a major influence on KS development. It also suggests that KS as an AIDS-defining disease occurs earlier in the course of the chronic HIV infection than other opportunistic diseases. Reasons for geographical variations and its declining frequency as an initial AIDS diagnosis remain undetermined.

Factors associated with the development of Pneumocystis carinii pneumonia in 5,025 European patients with AIDS. AIDS in Europe Study Group

This study examined the factors associated with the development of a first episode of Pneumocystis carinii pneumonia (PCP) in 5,025 patients with AIDS, including 1,976 patients with primary PCP at the time of AIDS diagnosis and 635 with primary PCP occurring subsequently. Compared with untreated patients, patients treated with zidovudine were at similar risk of developing PCP during the first year of therapy but were at greater risk after longer intervals of treatment. The following factors were associated with an increased risk of PCP (either at the time of AIDS diagnosis or thereafter): lack of primary PCP prophylaxis, male homosexuality/bisexuality, diagnosis of AIDS in northern Europe, and CD4 cell count below 200 x 10(6)/L at the time of AIDS diagnosis. Patients with severe weight loss had a 60% higher risk of developing PCP during follow-up than those without such weight loss. Thus, the occurrence of PCP depended on geographic location, mode of acquisition of human immunodeficiency virus and AIDS, degree of immunodeficiency, and use of various treatment regimens.

[HIV-infected drug addicts in a clinic for infectious diseases are dissatisfied and desire more treatment]

In structured interviews with 171 HIV-positive iv drug abusers at the HIV clinic of Roslagstull Hospital in Stockholm, were investigated their current drug abuse and any wishes they might have as to their treatment. Over 75 per cent reported drugs abuse in the past 12-month period-chiefly iv heroin. Half of them reported that they lacked any form of counselling for their addiction, and something over 40 per cent wanted treatment- the predominant choice being methadone treatment. Despite methadone treatment having been found effective in cases of opiate-dependence, and in many cases a prerequisite of rehabilitation, the queues for it are very long in Sweden--up to two years. Adequate treatment for these patients needs to be made more rapidly available, and greater attention paid to the patients' own views. This is of the utmost importance, both epidemiologically and from the individual patient's point of view, and is a prerequisite in preventing the spread of HIV infection.

Treatment of non-invasive amoebiasis--a comparison between tinidazole and metronidazole

In a small pilot study the parasite cure rate (PCR) of non-invasive amoebiasis was compared after treatment with metronidazole 800 mg three times daily or tinidazole 600 mg twice daily for five days. Both treatment regimens were found to be highly unfavourable with PCRs of 44 and nil respectively, in contrast to previous published results showing PCR over 80%.

Treatment of non-invasive amoebiasis. A comparison between tinidazole alone and in combination with diloxanide furoate

Tinidazole (40 mg/kg body-weight in one daily dose for five days) and tinidazole (same dose) plus diloxanide furoate (20 mg/kg body-weight divided into three daily doses for 10 days) were compared as treatments for amoebiasis. The parasitic cure rates were 44 and 91% respectively. We cannot, therefore, recommend tinidazole alone in this dosage as a treatment for non-invasive amoebiasis.