Rectal cell-associated HIV-1 RNA: a new marker ready for the clinic.

Gut-associated lymphoid tissue is a huge reservoir for HIV-1. Developing new strategies to target "residual" HIV-1 in patients on effective therapy brings the need for an evaluation of tissue reservoirs in the clinic. We measured cell-associated HIV-1 RNA and DNA in blood and rectal biopsies from 23 patients, including 14 with undetectable viremia on HAART, by using an adaptation of commercially available tests. Rectal cell HIV-1 RNA was detected in all viremic patients, with median levels of 4.90 log(10) copies/million CD4. Although plasma viremia was found at a median of 3 copies/mL in "aviremic" patients, rectal cell HIV-1 RNA was detected in 28.5% with median levels of 5.17 log(10) copies/million CD4. Consequently, we propose to use this marker in future clinical trials targeting "residual" HIV-1 in patients with viremia below the detection limit.

Metabolic evaluation of HIV-infected patients receiving a regimen containing lopinavir/ritonavir (Kaletra).

PURPOSE: We have analyzed retrospectively the evolution of metabolic parameters in a cohort of 159 HIV-infected patients taking a lopinavir/ritonavir-containing regimen during a mean period of 15 months. METHOD: This study was completed by an additional evaluation after strict 12 hours fasting of total cholesterol (TC), HDL-c, LDL-c, triglycerides (TG), glucose, and insulin levels in a subset of 100 patients from the cohort. RESULTS: TC and TG levels increased early after introduction of lopinavir/ritonavir, but remained subsequently stable. After a median of 15 months, TC was greater than normal laboratory range in 46% of cases and TG levels were greater than normal laboratory range in 52% of cases. However, in nearly 90% of these cases, elevations were less than or equal to grade 2. These increases were dependant on CDC stage and lipid levels at lopinavir/ritonavir initiation. No impact on glucose metabolism was found. CONCLUSION: These results are particularly reassuring for the use of lopinavir/ritonavir in everyday practice.

Discrepancies between protease inhibitor concentrations and viral load in reservoirs and sanctuary sites in human immunodeficiency virus-infected patients.

The variable penetration of antiretroviral drugs into sanctuary sites may contribute to the differential evolution of human immunodeficiency virus (HIV) and the emergence of drug resistance. We evaluated the penetration of indinavir, nelfinavir, and lopinavir-ritonavir (lopinavir/r) in the central nervous system, genital tract, and lymphoid tissue and assessed the correlation with residual viral replication. Plasma, cerebrospinal fluid (CSF), semen, and lymph node biopsy samples were collected from 41 HIV-infected patients on stable highly active antiretroviral therapy regimens to determine drug concentrations and HIV RNA levels. When HIV RNA was detectable, sequencing of the reverse transcriptase and protease genes was performed. Ratios of the concentration in semen/concentration in plasma were 1.9 for indinavir, 0.08 for nelfinavir, and 0.07 for lopinavir. Only indinavir was detectable in CSF, with a concentration in CSF/concentration in plasma ratio of 0.17. Differential penetration into lymphoid tissue was observed, with concentration in lymph node tissue/concentration in plasma ratios of 2.07, 0.58, and 0.21 for indinavir, nelfinavir, and lopinavir, respectively. HIV RNA levels were <50 copies/ml in all CSF samples of patients in whom HIV RNA was not detectable in plasma. HIV RNA was detectable in the semen of three patients (two patients receiving nelfinavir and one patient receiving lopinavir/r), and its detection was associated with multiple resistance mutations, while the viral load in plasma was undetectable. HIV RNA was detectable in all lymph node tissue samples. Differential drug penetration was observed among the three protease inhibitors in the sanctuary sites, but there was no correlation between drug levels and HIV RNA levels, suggesting that multiple factors are involved in the persistence of viral reservoirs. Further studies are required to clarify the role and clinical relevance of drug penetration in sanctuaries in terms of long-term efficacy and drug resistance.

The HYDILE trial: efficacy and tolerance of a quadruple combination of reverse transcriptase inhibitors versus the same regimen plus hydroxyurea or hydroxyurea and interleukin-2 in HIV-infected patients failing protease inhibitor-based combinations.

PURPOSE: To compare the efficacy and tolerance of a stavudine (d4T), didanosine (ddI), efavirenz (EFV), and abacavir (ABC) combination regimen with an identical regimen plus hydroxyurea (HU), or plus HU and interleukin-2 (IL-2), in patients failing protease inhibitor-based combinations and naive of EFV and ABC. METHOD: This was a randomized prospective trial in 69 HIV-infected patients recruited in one clinical center. Antiretroviral drugs were administered at standard doses according to weight. HU was added at week 6 at 500 mg twice daily. Three courses of IL-2 were given subcutaneously at 4.5 MU twice daily for 5 consecutive days, between weeks 24 and 40. The proportion of patients reaching plasma HIV-1 RNA <200 and <50 copies/mL was compared in the three trial groups at weeks 6, 24, and 48 using intent-to-treat and as-treated analyses. CD4+ T-cell count changes from baseline were also assessed at the same time points, along with anthropometric and metabolic measurements. RESULTS: After 48 weeks, only 25% of patients receiving antiretrovirals had plasma HIV-1 RNA <200 copies/mL versus 59.1% in the group receiving HU and 56.5% in the group receiving HU and IL-2 (intent-to-treat; p <.01). At the 50 copies/mL cutoff, the results were 20.8%, 54.5%, and 47.8%, respectively. Most treatment discontinuations were due to failure in the first group and adverse events in the two others. A median decline of 27 CD4+ cells was observed in patients receiving antiretrovirals plus HU, against a gain of 78-118 cells at week 48 in patients receiving antiretrovirals alone or in combination with HU and IL-2. More patients were affected by clinical fat atrophy symptoms at week 48 than at baseline. Additionally, a trend toward increased cholesterol levels was observed throughout the study. CONCLUSION: During this trial, virologic response in patients failing previous regimens was clearly enhanced by the addition of HU, despite d4T and ddI recycling. Although adverse events were more frequent in the HU-containing arms, no unexpected toxicity was observed and the blunted CD4 response prompted by HU was corrected by the addition of IL-2. The combination of HU with reverse transcriptase inhibitors can therefore be regarded as a valuable alternative for patients with few remaining therapeutic options.

Differences in the detection of three HIV-1 protease inhibitors in non-blood compartments: clinical correlations.

PURPOSE: To study the presence of three HIV-1 protease inhibitors (PIs) in the cerebrospinal fluid (CSF), semen, and lymph nodes and to assess the correlations with residual viral replication in these compartments. METHOD: We performed a cross-sectional analysis of sanctuary samples from 41 HIV-infected patients on stable highly active antiretroviral therapy (HAART) regimens containing indinavir, nelfinavir, or lopinavir combined with ritonavir (lopinavir/r) and a longitudinal analysis of PI levels and HIV-1 RNA in plasma and CSF of 6 additional patients on nelfinavir or lopinavir/r monotherapy (3 cases each). Plasma, CSF, semen, and a lymph node (LN) biopsy were taken on the same day. Samples were assayed for PI concentrations, HIV-1 RNA levels, and, when detectable, sequencing of the reverse transcriptase and protease genes on seminal viral RNA. RESULTS: In the cross-sectional analysis, the CSF/plasma ratio was 0.14 for indinavir. Nelfinavir and lopinavir/r were consistently undetectable in CSF. The semen/plasma ratio was 1.9 for indinavir, 0.07 for nelfinavir, and 0.07 for lopinavir. The LN/plasma ratio was 2.07 for indinavir, 0.58 for nelfinavir, 0.21 for lopinavir, and 0.64 for ritonavir. Plasma HIV-1 RNA was <50 copies/mL in 28 patients and was detectable in 13 patients. HIV-1 RNA was <50 copies/mL in CSF samples when plasma RNA was undetectable. Three semen samples taken from patients with viremia <50 copies/mL showed detectable HIV-1 RNA with resistance mutations. HIV-1 RNA was detectable in all LNs, with no differences in patients on indinavir compared with those on nelfinavir or lopinavir/r. In the longitudinal analysis, HIV-1 RNA decreased in the plasma of the 6 patients on nelfinavir or lopinavir/r monotherapy, although CSF HIV-1 RNA decreased only in patients on lopinavir/r. CONCLUSION: Major differences exist between PIs in terms of detection in non-blood compartments. An undetectable PI level in CSF does not rule out drug activity in the brain for lopinavir/r, although this is not the case for nelfinavir. Poor penetration of PIs in semen in some patients can lead to double nucleoside therapy in this compartment. The persistence of HIV-1 RNA in LNs does not seem to be related to PI levels in this tissue.