[Therapeutic strategies for HIV infection: early response to antiretroviral treatment, predictive factor for the longer term response]

Despite the wide armamentarium available against the human immunodeficiency virus, the efficacy of therapeutic molecules is reduced by the selection of resistant viral strains. Several data argue in favour of an early control of viral replication ever since the first treatment: the intensity of the initial viral replication, as well as results of studies on antiretroviral drugs given as first line treatment and on the early inhibitory response of viral replication. Although an early control is essential for long-term antiviral success, the optimal time limit for the virologic response still needs to be established early knowledge of the virologic response could prove useful in the evaluation of new and more successful therapeutic combinations. Nevertheless, the impact of an earlier control of viral replication on long-term treatment efficacy and on the prevention of resistance emergence deserves further investigation.

Impact of Newly Available Drugs on Clinical Progression in Patients with Virological Failure after Exposure to Three Classes of Antiretrovirals

Objective

To study the prognosis of HIV-infected patients with virological failure after exposure to three classes of antiretroviral drugs (ARVs).

Design

Cohort study. Setting: French Hospital Database on HIV.

Patients

Patients previously exposed to at least two nucleoside reverse transcriptase inhibitors (NRTIs), two protease inhibitors and one non-NRTI, with viral load (VL) values of >5000 copies/ml after the exposure criteria were met and a new treatment initiated between 1998 and 2001 with VL >5000 copies/ml.

Main outcome measures

Risk of new AIDS-defining-events (ADEs) or death from first introduction of a drug never used before occurring between 1998 and 2001 defined as baseline.

Results

The main baseline characteristics of the 1092 patients were: previous ADE in 49% of cases, median CD4 cell count 181 μl, median VL 4.9 log10 copies/ml, median duration of ARV therapy 5.0 years and previous exposure to a median of nine ARVs. The crude progression rates were 20.1/100 patient-years among patients included in 1998, 15.1 in 1999, 11.1 in 2000 and 8.6 in 2001. After adjustment for baseline characteristics, the calendar year of inclusion was associated with the risk of clinical progression ( P<0.001). When the types of newly available drugs used at baseline or during follow-up were introduced into the model, year of inclusion was no longer associated with the risk of clinical progression ( P=0.42), while exposure to amprenavir/r, lopinavir/r, abacavir or tenofovir was associated with a lower risk.

Conclusions

The clinical prognosis of heavily pretreated patients experiencing virological failure improved between 1998 and 2001, mainly thanks to the use of newly available drugs with more favourable resistance profiles.

Impact of Insertions in the HIV-1 P6 Ptapp Region on the Virological Response to Amprenavir

We evaluated the impact of genetic changes within p6Gag gene on the virological response (VR, mean decrease in plasma viral load at week 12) to unboosted amprenavir (APV). Gag-protease fragments, including gag p2, p7, p1, p6 regions and whole protease (PR) were sequenced from baseline plasma specimens of 84 highly pre-treated but APV-naive patients included in the NARVAL (ANRS 088) trial. The correlation between baseline p6Gag polymorphism, PR mutations, baseline characteristics and VR to APV was analysed in univariate analysis. Insertions (P459Ins) within p6 protein, leading to partial or complete duplication of the PTAPP motif, were significantly associated with a decreased VR (P459Ins versus wild-type; –0.3 ±0.8 vs –1.1 ±1.2 log copies/ml, P=0.007) and were more frequent when the V82A/F/T/S PR mutation was present ( P=0.020). In multivariate analysis, after adjustment on the predictive factors of the VR in the NARVAL trial and on the PR mutations linked with response, there was a strong trend to an association ( P=0.058) between the presence of P459Ins and an altered VR. In conclusion, these results suggest that insertions in the p6 region of HIV-1 gag gene may affect the VR, in highly pre-treated patients receiving an unboosted APV-containing regimen.

Triple Nucleoside Combination Zidovudine/Lamivudine/Abacavir versus Zidovudine/Lamivudine/Nelfinavir as First-Line Therapy in HIV-1-Infected Adults: A Randomized Trial

Objective

To compare the efficacy and safety of a triple nucleoside combination to a protease inhibitor-containing triple regimen as first-line antiretroviral therapy (ART) in HIV-1-infected patients.

Design

Open-label study in HIV-1-infected ART-naive adults, randomized to receive either Combivir® (lamivudine 150 mg/zidovudine 300 mg twice daily) + abacavir (300 mg twice daily), or Combivir® + nelfinavir (750 mg every 8 h) for 48 weeks. Plasma HIV-1 RNA, CD4 cell count and adverse events were assessed at baseline and weeks 4, 8, 16, 24, 32, 40 and 48.

Results

195 subjects (131 men, 64 women), median age 34 years, were randomized: 98 received combivir/abacavir and 97 combivir/nelfinavir. Baseline median plasma HIV-1 RNA was 4.2 log10 copies/ml [Interquartile range (IQR): 3.7-4.5.2] and 4.1 log10 copies/ml (IQR: 3.8–4.6), respectively. Baseline median CD4 cell count was 387 cells/mm3 (IQR: 194–501) and 449 cells/mm3 (IQR: 334–605), respectively. Nine patients (3 vs 6, respectively) did not start treatment or did not have any available efficacy data. At week 48, using the intent to treat analysis (switch/missing equals failure), plasma HIV-1 RNA was <50 copies/ml in 54/95 (57%) and 53/91 (58%) of subjects, respectively. Median CD4 increase was +110 and +120 cells/mm3, respectively. Possible hypersensitivity reactions to abacavir were reported in four subjects (4%).

Conclusion

The triple nucleoside combination combivir/abacavir is well tolerated as a first-line ART regimen in HIV-1-infected adults, with comparable antiviral activity to a nelfinavir-containing regimen at week 48.

Immunological and virological features of HIV-infected patients with increasing CD4 cell numbers despite virological failure during protease inhibitor-based therapy

OBJECTIVES

To investigate the extent of functional T cell recovery and to characterize plasma virus and virus producing cells in patients with increasing CD4 cell counts despite virological failure during protease inhibitor (PI) based therapy.

METHODS

The study group included 13 patients who were treated for at least 12 months with a PI based regimen and were selected on the basis of a sustained immunological response (increase of > 70 CD4 cells/microL) despite virological failure (< 1 log10 copies/mL decrease in HIV-1 RNA plasma levels).

RESULTS

Compared to a historical series of 11 complete responders with less advanced disease, the proportion of memory CD4 T cells was significantly higher (67.8+/-17.8 vs. 52.8+/-11.0; P=0.045) and the proportion of naive CD4 T cells significantly lower (30.5+/-14.8 vs. 45.0+/-10.4, P=0.021) in patients who were immunological responders/virological nonresponders. In those patients, ongoing viral replication was associated with a strong activation of circulating CD8 T lymphocytes; interleukin-2 production remained decreased. CD4 T cell reactivity to cytomegalovirus proteins was observed in nine of 11 patients tested. In the study group, the proportion of infectious virus present in plasma as well as the levels of intracellular viral replication were similar to those measured in untreated patients. Virological failure in this group of patients probably resulted from pre-existing mutations in the reverse transcriptase gene.

CONCLUSIONS

This study of patients with increasing CD4 cell numbers despite virological failure shows the persistence of immune activation and partial immune restoration with no evidence of specific viral dynamics in vivo.

Sequential occurrence of thyroid autoantibodies and Graves' disease after immune restoration in severely immunocompromised human immunodeficiency virus-1-infected patients

We analyzed the kinetics of CD4 cells, human immunodeficiency virus (HIV) viral load, and autoantibodies in acquired immune deficiency syndrome patients with Graves' disease (GD) after immune restoration on highly active antiretroviral therapy (HAART; retrospective study). Five patients (median age, 41 yr) were diagnosed with GD after 20 (range, 14-22) months on HAART on the basis of clinical and biological hyperthyroidism, diffuse hyperfixation of thyroid scan, and the presence of anti-TSH receptor (anti-TSHR) antibodies (Ab). GD was diagnosed several months after the plasma HIV ribonucleic acid load became undetectable, when the CD4+ cell count had risen from 14 (range, 0-62) to 340 (range, 163-460) x 10(6) cells/L. Antithyroid peroxidase (anti-TPO) and anti-TSHRAb appeared 14 (range, 9-18) and 14 (range, 11-20) months after starting HAART and 12 (range, 6-15) and 11 (range, 9-17) months after the increase in CD4+ cells. In 3 patients, TPOAb preceded TSHRAb by 3-10 months. No other autoantibodies were detected. Thyroid antibodies were absent in a group of 55 HIV-1-positive patients with comparable response to HAART and no symptoms of hyperthyroidism (cross-sectional study). Thyroid-specific autoimmunity can occur upon immune restoration with HAART. Our observations suggest a relationship between thymus-dependent immune reconstitution after immunosuppression and autoimmunity and may provide insight into the pathophysiology of GD.

Monitoring plasma levels of ganciclovir in AIDS patients receiving oral ganciclovir as maintenance therapy for CMV retinitis

OBJECTIVES

To investigate whether low ganciclovir serum levels in patients on maintenance oral ganciclovir therapy are associated with recurrence of CMV retinitis.

METHODS

A prospective study of the plasma concentration of ganciclovir after initiation of maintenance oral ganciclovir therapy in 14 AIDS patients who had recovered from acute cytomegalovirus (CMV) retinitis.

RESULTS

Five of the 14 patients exhibited a mean time to recurrence of 37 days. The mean trough plasma concentration of ganciclovir in these patients after 1 month of oral ganciclovir therapy, was 0.40 +/- 0.30 mg/L. Nine patients had a mean time of progression of 263 days. The mean trough plasma concentration of ganciclovir in the latter patients was 0.80 +/- 0.60 mg/L.

CONCLUSIONS

Patients exhibiting trough plasma levels of ganciclovir below 0.6 mg/L may be at higher risk of progression than patients who exhibited levels above 0.6 mg/L.

The sequential occurrence of pol 215 and pol 41 zidovudine resistance mutations is associated in an additive fashion with low CD4 cell counts and high plasma and cellular HIV viral load

We report on a cross-sectional study of virological and immunological surrogate markers of HIV infection in 115 patients for whom a determination of the pol 215 and pol 41 zidovudine (ZDV) resistance mutations had been described between January 1995 and February 1996. The patients received ZDV alone or a combination of ZDV and zalcitabine or didanosine. A total of 55, 15 and 45 patients exhibited a wild (W), a mixed (MIX) or a mutant (M) genotype at codon pol 215, respectively; 85, 10 and 20 patients exhibited a W, a MIX or a M genotype at codon pol 41, respectively. Patients exhibiting the pol 215 M genotype had lower CD4 cells, higher plasma viral load and higher proviral burden than patients exhibiting the pol 215 W genotype. Patients who had variants exhibiting both pol 215 M and pol 41 M or MIX genotypes had significantly worsened surrogate marker values than patients having variants only carrying the pol 215 M genotype. These observations demonstrate that the two mutations additively associate with pejorative surrogate markers.

Genetically related human immunodeficiency virus type 1 in three adults of a family with no identified risk factor for intrafamilial transmission

A small number of cases of human immunodeficiency virus (HIV) infection have been reported in individuals with no identified risk factors for transmission. We report on the seroconversion of the 61-year-old mother and the subsequent finding of HIV seropositivity in the 66-year-old father of a 31-year-old AIDS patient. Extensive investigation failed to identify any risk factor for intrafamilial transmission. We conducted a genetic analysis and determined the amino acid signature patterns of the V3, V4, and V5 hypervariable domains and flanking regions in the HIV-1 gp120 env gene of 26 clones derived from proviral DNA in peripheral blood mononuclear cells of the members of the family. env sequences of the viruses isolated from the patients were compared with sequences of HIV-1 subtype B viruses from Europe and local field isolates. Phylogenetic analysis revealed that the sequences of the viruses isolated from the patients were genetically related and formed an intrafamilial cluster of HIV-1 distinct from other subtype B viruses. Interindividual nucleotide variability in the C2-V3 and V4-C4-V5 domains ranged between 1.2 and 5.0% and between 2.2 and 7.5%, respectively, whereas divergence between HIV strains from the patients and control viral strains ranged from 6.6 to 29.3%. The amino acid signature patterns of viral clones from the three patients were closely related. In the C2-V3 region, two minor clones derived from the son's virus showed less nucleotide divergence (mean, 3.5 and 3.9%) than did the clones derived from the viruses of both parents or the seven other predominant clones derived from the virus from the son (mean, 5.4%). The top of the V3 loop of the last two clones and of all viral clones from the parents exhibited an unusual GPGG sequence. This is the first report of genotypic relatedness of HIV-1 in three adults of the same family in the absence of identified risk factor for transmission between the members of the family. Our findings suggest that atypical transmission of HIV may occur.

[Lactic acidosis and hepatic mitochondrial changes during a treatment with zidovudine]

Adverse effects of zidovudine, which mainly result in myopathies and hematological disorders, could be due to multitissular mitochondrial toxicity of the drug. During zidovudine treatment, most cases of lactic acidosis have been attributed to mitochondrial myopathy. We report a case of hepatocellular failure with lactic acidosis in a 33 year-old patient with the human immunodeficiency virus infection and treated with zidovudine for 8 months. Liver biopsy showed massive macrovacuolar steatosis and ultrastructural mitochondrial abnormalities similar to those previously described in the skeletal muscle. This is the second reported case of lactic acidosis and hepatocellular failure which is probably related to hepatic mitochondrial dysfunction caused by zidovudine.

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.

Low plasma concentrations achieved with conventional schedules of administration of ganciclovir in patients with AIDS

Plasma concentration of ganciclovir was studied prospectively in 15 AIDS patients treated for acute cytomegalovirus (CMV) retinitis. Ganciclovir was administered at a mean dose of 10.3 +/- 0.6 mg/kg/day. The mean trough plasma concentration was 0.6 +/- 0.3 mg/L (n = 24), and the mean peak concentration was 7.2 +/- 2.4 mg/L (n = 6). In 12 patients, trough concentrations were below the range that has been associated with effective treatment. Low trough concentrations were associated with treatment failure in 6 patients. Following an increase in the daily dose, improvement was observed in 4 of the 6 patients. These results suggest that low plasma ganciclovir levels are associated with the failure of therapy. Monitoring the plasma concentration of ganciclovir may thus be useful before considering the virus to be resistant to the drug or before switching from ganciclovir to foscarnet.

Comparison of cervicovaginal humoral immunity in clinically asymptomatic (CDC A1 and A2 category) patients with HIV-1 and HIV-2 infection

Paired sera and cervicovaginal secretions (CVS) from 11 HIV-1- and 11 HIV-2-infected women, all clinically asymptomatic (CDC A1 and A2 categories), were analyzed for total IgG, IgA, albumin (HSA), IgG, and IgA antibodies to env-encoded surface glycoproteins of HIV-1 (gp160) and of HIV-2 (gp105), by comparison to 15 age-matched healthy controls. Secretion rates of IgG and IgA into CVS were evaluated by calculation of their relative coefficients of excretion (RCE) by reference to HSA. Cervicovaginal production of anti-HIV antibodies was evaluated by comparison between specific antibody activities of IgG and of IgA to HIV in CVS were, respectively, 6- and 4-fold increased, whereas the secretion rate of total IgG was 2.1-fold increased and that of total IgA was 2.5-fold reduced. In contrast, total IgG and IgA as well as their secretion rates were normal in HIV-2-infected women. In HIV-1- but not in HIV-2-infected women, HSA levels in cervicovaginal washings were twofold increased, demonstrating alteration of the mucosal barrier in HIV-1 infection. In HIV-1-infected patients, IgG and IgA to gp160 were detected in all sera and CVS. In HIV-2-infected patients, IgG to gp105 was detected in all sera and CVS, whereas IgA to gp105 could be detected in only half of sera and one-third of CVS. Cross-reactivity by IgG and/or IgA to HIV-1 or HIV-2 against the surface glycoprotein of the other HIV type was observed in sera as well as in CVS, and more frequently in HIV-2- than in HIV-1-infected women. Finally, the mean specific activities of IgG and of IgA to gp160 or gp105 were higher in CVS than in sera, evidencing a possible local synthesis of both isotypes in HIV-1 as well as in HIV-2 infections. As early as the asymptomatic stages, HIV-1 affects the cervicovaginal mucosa more than HIV-2 does, suggesting higher viral replication within the female genital tract in HIV-1 infection than in HIV-2 infection.

[Spinal cord toxoplasmosis and AIDS]

Toxoplasmosis is the most common brain parasitic infection in acquired immunodeficiency syndrome (AIDS). Spinal cord localisations are still rare (2 cases with cerebral involvement, 2 cases without). A case of both spinal cord and cerebral involvement is reported. MR imaging was performed because of sensory level (L1). A focal conus medullaris enlargement was seen, iso intense on T1 weighted images. This lesion was hyperintense on T2 weighted sequence, and was homogeneously enhanced after Gadolinium on T1 weighted images. A medullary oedema was noted. A toxoplasmosis treatment was initiated, without corticotherapy. MR imaging performed one month later (D30), while important clinical improvements were seen, pointed out normal thickness of conus medullaris, without enhancement after Gadolinium. Disease lesions in AIDS with focal spinal cord processes are reviewed, and diagnostic work-up is discussed. Spinal cord single lesion, associated or not with brain involvements should be treated as a toxoplasmic infection, with MR imaging follow up. This work up should avoid medullary biopsy, still required in case of treatment failure. Cerebral involvements, with multiples lesions, can mask medullary localisation.

Chicken pox and acute monocytic leukaemia skin lesions in an HIV-seropositive man

Lymphoid neoplasia is now well known to occur in patients with human immunodeficiency virus (HIV) infection but the first case of acute monocytic leukaemia in an HIV-seropositive man has been only recently described. We report the case of an HIV-infected patient who simultaneously developed skin lesions of acute monocytic leukaemia and chicken pox. We suggest that HIV may produce a malignant transformation of monocytic cells.

Zidovudine inhibits functional extracellular monocytic interleukin-1

Zidovudine (AZT) penetrates human monocytes to exert its antiretroviral activity at the level of reverse transcriptase in infected cells. Stimulation of normal human monocytes with lipopolysaccharide (LPS) results in the transcription of interleukin-1 (IL-1) genes, the intracellular accumulation of IL-1 alpha and IL-1 beta precursors, and the subsequent extracellular release of functional IL-1 beta. The present study demonstrates that zidovudine inhibits the extracellular release of IL-1 activity without affecting the generation of intracellular IL-1 or the amount of released IL-1 beta protein. Similar results were observed with monocytes from normal individuals and monocytes from patients with AIDS. Since IL-1 may upregulate the expression of HIV genes in infected cells, the inhibitory effect of zidovudine on the release of functional IL-1 may be relevant for the beneficial effect of the drug in HIV infection.

HIV infection is associated with the spontaneous production of interleukin-1 (IL-1) in vivo and with an abnormal release of IL-1 alpha in vitro

Interleukin-1 (IL-1) is not constitutively produced by normal human monocytes. We have investigated the production of cell-associated IL-1 in uncultured unstimulated adherent monocytes from HIV-infected patients, which reflects ongoing generation of IL-1 by the cells in vivo. High levels of cell-associated IL-1 activity and of cell-associated IL-1 alpha and IL-1 beta antigens were found in monocytes from HIV-infected patients as compared with those found in monocytes from normal individuals. Amounts of cell-associated IL-1 were high in patients with AIDS and in patients from Centers for Disease Control groups II and III. Serum-free culture for 24 h of monocytes from HIV-infected individuals in the absence of lipopolysaccharides (LPS) resulted in spontaneous release of IL-1 activity from the cells whereas no release occurred upon culture of normal cells. Stimulation of monocytes with LPS induced the release of IL-1 alpha and IL-1 beta from cells of infected patients. Only IL-1 beta was released from cells of normal individuals. Thus, circulating monocytes from HIV-infected patients are triggered to produce IL-1 in vivo. The present study also indicates that HIV infection is associated with an acquired defect in the intracellular processes regulating IL-1 secretion.