Hamid Hasson

Lamivudine monotherapy in HIV-1-infected patients harbouring a lamivudine-resistant virus: a randomized pilot study (E-184V study).

Objective:We compared the immunological and clinical outcomes of lamivudine monotherapy and complete therapy interruption in the treatment of HIV-1-infected patients harbouring lamivudine-resistant virus. Methods:This 48-week, open-label pilot study randomly assigned HIV-infected patients receiving lamivudine-containing HAART and harbouring the M184V mutation to monotherapy with lamivudine 300 mg once daily (lamivudine group) or the discontinuation of all antiretroviral drugs (TI group). The primary endpoint was the occurrence of immunological or clinical failure; immunological failure was defined as the first report of a CD4 T-cell count less than 350 cells/μl, and clinical failure as the occurrence of a Centers for Disease Control and Prevention grade B or C event. The data were analysed on the basis of the intention-to-treat principle. Results:By week 48, 20 of 29 patients in the TI group (69%; 95% CI 51–83%) and 12 of 29 in the lamivudine group (41%; 95% CI 26–59%) had discontinued the study because of immunological or clinical failure, which was significantly delayed in the lamivudine group (P = 0.018). Only patients in the TI group (6/29, 20.7%) experienced grade 3–4 clinical adverse events at least possibly related to HIV-1 (P = 0.02). The mean decline in CD4 cell percentage, viral rebound and recovery of HIV-1 replication capacity were significantly lower in the lamivudine group. The 24-week virological and immunological response after therapy resumption in patients who prematurely discontinued the study was similar in the two groups. Conclusion:In HIV-1-infected patients harbouring a lamivudine-resistant virus, lamivudine monotherapy may lead to a better immunological and clinical outcome than complete therapy interruption.

Genotype and Phenotype Patterns of Human Immunodeficiency Virus Type 1 Resistance to Enfuvirtide during Long-Term Treatment

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) fusion inhibitor enfuvirtide has recently been introduced into clinical practice and has exhibited efficient anti-HIV-1 activity in combination with other antiretroviral agents. In the present study, we addressed the effect of long-term treatment with enfuvirtide on the intrahost evolution of HIV-1. The genotype and phenotype patterns and the relative replication capacity (rRC) of enfuvirtide-resistant HIV-1 mutants were evaluated in samples from 11 subjects (7 virological nonresponders and 4 responders) who received the compound for more than 1 year in combination with different regimens. Selection of one or more mutations clustering in a sequence (amino acids 36 to 45) of the gp41 N-terminal heptad repeat was observed in samples from the seven virological nonresponders but not in those from responders. In two subjects who discontinued enfuvirtide, reversion of the resistant genotype was detected within 3 months. Recombinant clones bearing mutated gp41 sequences displayed reduced susceptibilities to enfuvirtide, with the 50% inhibitory concentrations (IC50s) ranging from 0.6 to 12.8 μg/ml, whereas the IC50 for isolates with baseline sequences was 0.013 ± 0.010 μg/ml. Interestingly, long-term monitoring of resistant variants provided evidence that ongoing adaptation to the drug is paralleled by phenotypic changes. A limited drop in the rRC in the absence of drug was observed for clones from four of the seven nonresponders bearing mutations associated with resistance. Overall, the data indicate that the different genotype patterns associated with a detectable degree of HIV-1 resistance to enfuvirtide generated during long-term treatments are characterized by a substantially low genetic barrier, possible ongoing adaptation with increased degrees of resistance, and limited influence on the viral rRC.

Osteoprotegerin and bone turnover markers in heavily pretreated HIV‐infected patients

To characterize osteoprotegerin (OPG) levels, bone remodelling and bone mineral density (BMD) in heavily pretreated HIV‐infected patients on antiretroviral therapy, and to evaluate the clinical factors associated with bone density decline.

Resistance to amprenavir before and after treatment with lopinavir/ritonavir in highly protease inhibitor-experienced HIV patients

Anti-hepatitis C virus (HCV) treatment combining IFN-alpha and ribavirin (IFN+R) has still poorly defined effects on immune responses. Frequencies of T helper (Th) type 1 cells specific for HCV, cytomegalovirus (CMV) and HIV were measured in chronically HCV-infected patients with or without HIV co-infection during IFN+R treatment. Although scarce, peripheral blood HCV-specific Th1 cells did not change significantly, while frequencies of HIV and CMV-specific Th1 cells decreased in co-infected patients independently of CD4 cell count changes. This suggests that IFN+R therapy might compromise virus-specific immune defenses in immunosuppressed patients.

Evolutionary Characteristics of HIV Type 1 Variants Resistant to Protease Inhibitors in the Absence of Drug-Selective Pressure

To understand the evolutionary characteristics of HIV-1 variants resistant to protease inhibitors (PI), the replicating plasma virus was analyzed in three patients shifted to PI-sparing regimen after virological failure. The dynamic features of carryover mutations associated with PI resistance in the absence of selective pressure on the protease gene indicate that viral variants resistant to reverse transcriptase inhibitors and bearing mutations of the protease sequence can maintain efficient replication capacity in vivo.

Relation between CD4 cell counts and HIV RNA levels at onset of opportunistic infections.

Objective: To evaluate the relation between CD4 and HIV RNA levels at the onset of specific opportunistic infections (OIs) in HIV‐infected patients. Design and Methods: The OIs occurring between June 1996 and December 1998 were retrospectively reviewed, considering only the episodes of major and minor OIs in patients with simultaneously available CD4 and plasma HIV RNA determinations before clinical onset who had been untreated or on stable antiretroviral therapy (ART) for at least 2 months. Results: Two hundred seventy‐four episodes of different OIs were considered in 216 patients; the median CD4 count was 35 cells/mm3 (range: 0‐1154 cells/mm3), and the median HIV RNA count was 5.1 log cp/mL (range: <1.9‐6.7 log copies/ml). The different HIV RNA levels were significantly associated with different OIs regardless of CD4 and ART (p < .0001), even when only those occurring in patients with a CD4 count of ≤50 cells/mm3 were considered (p = .0049). Kaposi sarcoma, esophageal candidiasis, oropharyngeal candidiasis, and Mycobacterium avium complex disease were associated with significantly above‐average median HIV RNA levels, and varicella‐zoster virus infection was associated with below‐average levels. Conclusions: Different OIs are associated at their onset with significantly different HIV RNA levels, regardless of CD4 cell counts and ART.

Non-invasive fibrosis biomarkers - APRI and Forns - are associated with liver stiffness in HIV-monoinfected patients receiving antiretroviral drugs.

HIV‐monoinfected patients are susceptible to liver injury by different factors and may develop liver fibrosis, which requires adequate clinical management in terms of therapy and disease monitoring. We aimed to evaluate the presence of liver fibrosis identified by transient elastography (TE), its relationships with indirect biochemical markers [the aspartate aminotransferase/platelet ratio index (APRI), the Forns index and FIB‐4] and its predictive factors in HIV‐monoinfected patients receiving antiretroviral therapy (ART).

Pharmacokinetic and pharmacodynamic determinants of early virological response to enfuvirtide-based regimens in HIV-positive patients

BACKGROUND Early virological response (VR) to enfuvirtide-based salvage regimens at week 12 has been described as a predictor of long-term therapeutic success. The relationship between enfuvirtide plasma exposure and VR has not yet been investigated in the clinical setting. Our aim was to investigate the role of enfuvirtide plasma exposure as a determinant of early VR in the clinical setting. METHODS Forty-two multidrug-experienced patients starting a salvage enfuvirtide-based regimen were prospectively evaluated over a 12 week period. HIV-RNA levels and enfuvirtide C(trough) were regularly measured. VR was considered as achievement of viral load (VL) undetectability and/or a decrease of more than 1 log at week 12. RESULTS Optimized background score (OBS) and enfuvirtide C(trough) concentrations were associated with VL decrease at week 12. An OBS > or =2 and enfuvirtide C(trough) >2100 ng/mL were associated with VR. The pharmacokinetic/pharmacodynamic (PK/PD) analysis confirmed this exposure-response relationship both in the total population and in different groups according to OBS <2 or > or =2. Higher estimates of IC(50) were calculated for the OBS <2 group when compared with the OBS > or =2 group (7551 versus 2330 ng/mL, respectively), without a marked difference in I(0) (0.31 versus 0.21 log) and I(max) (-2.64 versus -3.33 log). CONCLUSIONS Enfuvirtide plasma exposure and OBS were found to significantly influence the magnitude and rate of early VR. The PK/PD modelling of enfuvirtide concentrations was different in our clinical setting, compared with previous data obtained under trial conditions. Therefore, optimization of enfuvirtide plasma exposure could deserve further evaluation as a determinant of therapeutic response in HIV-positive patients.

Selective granulocyte/monocyte apheresis in the treatment of HIV-infected patients: short-term and long-term effects on immunological and virological parameters.

CD4 T cells constitute the major cellular target of HIV infection and, in the natural evolution of the disease, are gradually lost, leading to severe immunodeficiency. Highly active antiretroviral therapy (HAART) is generally effective in reducing HIV replication to undetectable levels and allows the recovery of CD4 T cells in the majority of patients treated. However, some sanctuaries of HIV replication persist even after years of effective HAART and are responsible for the rebound of viral replication when treatment is interrupted. Monocytes/macrophages are also infectable by HIV and are less susceptible to its cytopathic effects compared to CD4 T cells. Replication- competent HIV DNA is detectable in peripheral monocytes of patients under HAART. These cells may therefore contribute to the maintenance of HIV replication during treatment. In addition, both monocytes and granulocytes are abnormally activated during HIV infection and this results in overproduction of some pro-inflammatory cytokines, among them TNF-. For these reasons we tested whether the renewal of the pool of circulating monocytes and granulocytes by selective apheresis (G1 apheresis) could influence some key immunological and virological parameters in HAART-treated patients. The results showed that treatment with G1 apheresis without discontinuation of HAART results in an accelerated immune reconstitution with sustained increases in CD4 T cell counts in those patients who respond virologically to HAART. G1 apheresis is also followed by a strong reduction of TNF- and a reduction of cells bearing integrated HIV DNA. Taken together, the results indicate that G1 apheresis could be used to improve the immunological and virological response to HAART.

Ombitasvir/Paritaprevir/Ritonavir and Dasabuvir Combination Treatment in Patients with HIV/HCV Co-Infection: Results of an Italian Compassionate Use Program.

Patients co-infected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are at high risk of liver disease progression. We report a favorable safety profile and SVR12 rates of 96.7% among HIV/HCV co-infected patients participating in an Italian compassionate-use program of ombitasvir/paritaprevir/ritonavir + dasabuvir (OBV/PTV/r + DSV) ± ribavirin (RBV).