Alessandra Fantauzzi

Idiopathic CD4+ Lymphocytopenia May Be due to Decreased Bone Marrow Clonogenic Capability

Background: Idiopathic CD4+ lymphocytopenia is defined by a stable decrease of CD4+ T cells in the absence of any known cause of immune deficiency. The mechanisms responsible for the immunological impairment are still unknown, but a regenerative failure of hematopoietic stem/progenitor cells has been hypothesized. Methods: We evaluated in the bone marrow (BM) of 5 patients with idiopathic CD4+ lymphocytopenia the phenotype of BM progenitor cells, their differentiation capacity with colony-forming cells and long-term culture-initiating cell assays, in parallel with the spontaneous IL-7 production in the patient sera. Results: Compared with controls, a regenerative failure of hematopoietic stem cells has been observed, both in ‘committed’ and in ‘uncommitted’ progenitor cells, despite high IL-7 serum levels. The percentage of phenotypically primitive CD34+CD38–DR+ cells (this includes the lymphoid precursor cells) was decreased, suggesting an involvement of the more primitive BM compartment in the de novo T cell generation. Conclusions: Despite the low number of patients, due to the low incidence of the disease, the decrease of primitive precursors sustains the possibility that diminished stem cell precursors might contribute to the development of CD4+ T cell depletion.

Decreased apoptosis of bone marrow progenitor cells in HIV-1-infected patients during highly active antiretroviral therapy

Impaired haematopoiesis during HIV-1 infection may be caused by the overproduction of inflammatory cytokines by immune cells at the bone marrow level inducing Fas-mediated apoptosis of stem progenitors. In this study, we evaluated the effects of highly active antiretroviral therapy on apoptosis of CD34+ stem cells derived from the bone marrow of HIV-1-infected patients, and observed decreased Fas expression on progenitor cells, in parallel with the diminution of TNF-alpha levels and the amelioration of clonogenic parameters.

Potential benefit of dolutegravir once daily: efficacy and safety.

The viral integrase enzyme has recently emerged as a primary alternative target to block HIV-1 replication, and integrase inhibitors are considered a pivotal new class of antiretroviral drugs. Dolutegravir is an investigational next-generation integrase inhibitor showing some novel and intriguing characteristics, ie, it has a favorable pharmacokinetic profile with a prolonged intracellular half-life, rendering feasible once-daily dosing without the need for ritonavir boosting and without regard to meals. Moreover, dolutegravir is primarily metabolized via uridine diphosphate glucuronosyltranferase 1A1, with a minor component of the cytochrome P450 3A4 isoform, thereby limiting drug–drug interactions. Furthermore, its metabolic profile enables coadministration with most of the other available antiretroviral agents without dose adjustment. Recent findings also demonstrate that dolutegravir has significant activity against HIV-1 isolates with resistance mutations associated with raltegravir and/or elvitegravir. The attributes of once-daily administration and the potential to treat integrase inhibitor-resistant viruses make dolutegravir an interesting and promising investigational drug. In this review, the main concerns about the efficacy and safety of dolutegravir as well as its resistance profile are explored by analysis of currently available data from preclinical and clinical studies.

Safety and therapeutic efficacy of the switch to maraviroc+darunavir/ritonavir in HIV/HCV coinfected patients: initial results from GUSTA study.

HIV/HCV coinfection is a risk factor for hepatic injury in patients receiving HAART and previous studies support a favourable effect of antiretroviral regimens including maraviroc (MVC) on the course of coinfection compared with other antiretroviral drugs. There are few observations about MVC use in simplified treatment of coinfected patients.Objective: To evaluate the efficacy and the safety of simplification to darunavir (DRV)/ritonavir (r)/maraviroc (MVC) in virologically HIV‐suppressed patients and to explore the effect of simplified treatment on coinfected patients.

Switch to maraviroc with darunavir/r, both QD, in patients with suppressed HIV-1 was well tolerated but virologically inferior to standard antiretroviral therapy: 48-Week results of a randomized trial

Objectives Primary study outcome was absence of treatment failure (virological failure, VF, or treatment interruption) per protocol at week 48. Methods Patients on 3-drug ART with stable HIV-1 RNA <50 copies/mL and CCR5-tropic virus were randomized 1:1 to maraviroc with darunavir/ritonavir qd (study arm) or continue current ART (continuation arm). Results In June 2015, 115 patients were evaluable for the primary outcome (56 study, 59 continuation arm). The study was discontinued due to excess of VF in the study arm (7 cases, 12.5%, vs 0 in the continuation arm, p = 0.005). The proportion free of treatment failure was 73.2% in the study and 59.3% in the continuation arm. Two participants in the study and 10 in the continuation arm discontinued therapy due to adverse events (p = 0.030). At VF, no emergent drug resistance was detected. Co-receptor tropism switched to non-R5 in one patient. Patients with VF reported lower adherence and had lower plasma drug levels. Femoral bone mineral density was significantly improved in the study arm. Conclusion Switching to maraviroc with darunavir/ritonavir qd in virologically suppressed patients was associated with improved tolerability but was virologically inferior to 3-drug therapy.

Rate and determinants of treatment response to different antiretroviral combination strategies in subjects presenting at HIV-1 diagnosis with advanced disease

BackgroundThe optimal therapeutic strategies for patients presenting with advanced disease at HIV-1 diagnosis are as yet incompletely defined.MethodsAll patients presenting at two outpatient clinics in 2000-2009 with an AIDS-defining clinical condition or a CD4+ T cell count < 200/μL at HIV-1 diagnosis were analyzed for the presence of combined immunovirological response, defined by the concomitant presence of an absolute number of CD4+ T cells > 200 cells/μL and a plasma HIV-1 RNA copy number < 50/mL after 12 months of HAART.ResultsAmong 102 evaluable patients, first-line regimens were protease inhibitors [PI]-based in 78 cases (77%) and efavirenz-based in 24 cases (23%). The overall response rate was 65% (95% CI: 55-74), with no differences by gender, age, nationality, route of transmission, hepatitis virus coinfections, presence of AIDS-defining clinical events, baseline HIV-1 viral load, or type of regimen (response rates with PI-based and efavirenz-based therapy: 63% and 71%, respectively, p = 0.474). Response rate was significantly better with higher baseline CD4+ T cell counts (78% with CD4+ ≥ 100/μL, compared to 50% with CD4+ < 100/μL; odds ratio: 3.5; 95% CI: 1.49-8.23, p = 0.003). Median time on first-line antiretroviral therapy was 24 months (interquartile range: 12-48). Switch to a second line treatment occurred in 57% of patients, mainly for simplification (57%), and was significantly more common with PI-based regimens [adjusted hazard ratios (AHR) with respect to efavirenz-based regimens: 3.88 for unboosted PIs (95% CI: 1.40-10.7, p = 0.009) and 4.21 for ritonavir-boosted PI (95%CI 1.7-10.4, p = 0.002)] and in older subjects (≥ 50 years) (AHR: 1.83; 95% CI: 1.02-3.31, p = 0.044). Overall mortality was low (3% after a median follow up of 48 months).ConclusionsOur data indicate that a favorable immunovirological response is possible in the majority of naive patients presenting at HIV-1 diagnosis with AIDS or low CD4+ T cell counts, and confirm that starting HAART with a more compromised immune system may be associated with a delayed and sometimes partial immune recovery. Simpler regimens may be preferable in this particular population.

Mutational Resistance Pattern of HIV Type 1 in CD14+ Monocytes, CD4+ T Cells, and Plasma from Treated Patients

It is necessary to understand the molecular nature of the virus population that persists in cellular reservoirs. To achieve this we planned to characterize the patterns of resistance of HIV-1 in CD14(+) monocytes, CD4(+) T cells, and plasma. Blood samples were collected from 42 patients treated for HIV: 32 were in virological failure and in 10 viremia was undetectable. CD14(+) and CD4(+) T cells were isolated using magnetic beads. Genotyping of the reverse transcriptase and protease gene of HIV-1 was undertaken using the fluorescent dideoxy-terminator method. Of the 32 patients in virological failure, 24 (75%) had resistance mutations in at least one compartment. The numbers and types of mutations from monocytes were the same as those detected in both CD4(+) T cell-associated virus and plasma in only 8% whereas in 71% monocytes exhibited a different mutation pattern. In 21% of patients, the profile of drug-resistant mutations in the virus from blood monocytes was identical to that in plasma but differed from that in CD4. In the 71% of patients with virological suppression, the genotypic resistance pattern differed between monocytes and CD4(+) T cells. Circulating monocytes may harbor a viral dominant population different from those viruses circulating in blood and archived in CD4(+) T cells. Hence, monocytes and other cellular reservoirs might serve as an indirect source of a drug-resistant viral variant.

Trends in drug resistance-associated mutations in a real-life cohort of Italian patients infected with HIV-1

Recent studies support the idea that human immunodeficiency virus type 1 (HIV-1) drug resistance is declining in developed countries. To help assess the current situation in Italy, the dynamics of drug resistance mutations in pol and integrase genes in plasma samples from HIV-1-positive patients attending Sapienza University Hospital, Rome, from 2003 to 2014 were analysed. In total, 1730 genotype resistance tests (GRTs) were retrospectively analysed. The prevalence of major drug resistance mutations (DRMs) was evaluated over time in the global population and in patients with antiretroviral therapy (ART) failure. Population dynamics, changes in ART administration, and HIV-1 RNA levels were analysed in combination with DRM trends. The global population showed a strong reduction in major DRMs to all drug classes. Over the 2003-2014 decade, resistance to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) declined from 80.0% to 18.7%, from 42.8% to 20.1% and from 74.2% to 8.3%, respectively (P<0.005 for all comparisons). However, only PI-associated mutations showed a significant decrease in patients experiencing ART failure. Interestingly, analysis of the integrase gene disclosed an increased resistance to integrase inhibitors, mainly regarding N155H, detected in 32.6% of raltegravir-treated patients in 2012-2014. In conclusion, in line with previous findings, this study shows that drug resistance is declining in Italy. However, the persistence of DRMs to NRTIs and NNRTIs suggests that despite adherence and treatment optimisation, some patients still experience therapy failure, emphasising the need for GRTs both in naïve and ART-failed patients.

Analysis of intracellular human immunodeficiency virus (HIV)‐1 drug resistance mutations in multi‐failed HIV‐1‐infected patients treated with a salvage regimen: 72‐week follow‐up

The human immunodeficiency virus (HIV) mutational archive of proviral DNA was monitored during a 72-week follow-up in 20 multidrug-experienced HIV-1-infected patients treated with a darunavir/ritonavir-based salvage therapy. At the beginning of the study, all patients harboured a number of intracellular drug resistance-associated mutations (RAMs) in peripheral blood mononuclear cells. In some patients, a significant fluctuation in the number of RAMs was observed during the observation period. However, all patients, notwithstanding the presence or the fluctuation of intracellular RAMs, showed a persistently undetectable viraemia. The data suggest that the archived resistant viral variants change during suppressive therapy, but that the variants are unable to re-emerge and to affect virological response.

No evidence of autoimmune disorders in antiretroviral-experienced HIV-1-infected individuals after long-term treatment with raltegravir

BACKGROUND The HIV integrase inhibitor raltegravir (RAL) can exacerbate autoimmune diseases in genetically predisposed mice. To evaluate whether this may occur in clinical practice, we clinically monitored HIV-positive patients treated with RAL and measured a panel of autoantibodies (auto-Abs) during the first year of RAL treatment. METHODS This was a longitudinal study in 109 antiretroviral-experienced patients who started a RAL-based regimen and were followed up for more than 2 years. A total of 45 patients were tested at baseline (before starting RAL) and after 12 months for the presence of the following auto-Abs: anti-nuclear antibodies, anti-double-stranded DNA, anti-smooth-muscle antibodies, anti-thyreoglobulin and anti-thyroid peroxidase antibodies, anti-cardiolipin immunoglobulin G and immunoglobulin M and anti-nuclear extractable antigens, including anti-SM ribonucleoprotein antigen, anti-Ro antigen and anti-La antigen. RESULTS A low rate of clinically relevant autoimmune diseases was observed at study entry (3/109; 2.8%; 95% CI 0.004, 0.059). No exacerbations were observed during follow-up. During the second year of RAL-based therapy a previously healthy patient developed psoriasis. At baseline, 17/45 (37.8%) patients tested for the presence of auto-Abs were positive. Most patients (n=13) were positive for anti-cardiolipin. After 12 months of RAL exposure, 9/45 patients were positive (20%; P=0.063). A positive correlation was found between HIV-1 RNA and anti-cardiolipin antibody concentration (P=0.010). CONCLUSIONS According to these results, RAL does not promote antibody-mediated immune disorders, at least not in the mid-term. A prolonged follow-up and an extension of the panel of auto-Abs are recommended to support these results.