Peter Gute

Virological and immunological effects of treatment interruptions in HIV-1 infected patients with treatment failure.

ObjectiveTo analyse the immunological and virological effects of treatment interruptions in HIV-1-infected patients with treatment failure and multidrug-resistant virus. MethodsDrug susceptibility was assessed using Antivirogram and genotypic analysis was based on population and clonal sequencing for 48 patients who had interrupted treatment (⩾ 2 months). ResultsTreatment interruption resulted in viral load increases (mean 0.7 log10 copies/ml;P = 0.0001) and CD4 cell count decreases (mean 89 × 106 cells/l;P = 0.0001). A complete shift to wild-type virus at the phenotypic, genotypic and clonal level was observed in 28/45 patients. These patients differed from those that did not show a shift to wild type in baseline CD4 cell counts (192 versus 59 × 106 cells/l;P = 0.007) and in the relationship between baseline viral load and CD4 cell count (no correlation versus a significant negative correlation;P = 0.008). Response to re-initiation of treatment fell with increasing viral load [relative hazard (RH) 0.33;P = 0.001] and with increasing total number of drugs with reduced susceptibility (RH 0.51;P = 0.0003); it improved with the number of new drugs received (RH 2.12;P = 0.0002) and a shift to wild type (RH 5.22, P = 0.006). ConclusionsChanges in surrogate markers suggest that treatment provided benefit in spite of virological failure and resistant virus. Although patients with a shift to wild-type virus responded better in the short term to treatment re-initiation, the long-term effects are not known and the risk of immune deterioration needs to be carefully considered.

Determinants of sustainable CD4 lymphocyte count increases in response to antiretroviral therapy.

OBJECTIVE HIV-induced CD4 lymphocyte depletion is partially reversed by antiretroviral therapy but it is unclear if the degree to which the CD4 count rises depends on viral suppression (if so, the extent of viral suppression required to achieve a maximal CD4 count rise), whether the rise is sustainable and whether it occurs in patients with CD4 count <10 x 10(6) cells/l. We aimed to address these issues. METHODS We studied CD4 count and plasma HIV RNA values every 4 weeks for 72 weeks in 154 patients starting indinavir-containing regimens. RESULTS Mean baseline HIV RNA and CD4 count were 4.8 log10 copies/ml and 180 x 10(6) cells/l, respectively. Overall, there was a mean increase in CD4 count of 143 x 10(6) cells/l by 72 weeks. The adjusted mean increase (adjusted for initial viral load, CD4 count and age) was strongly related to the mean viral suppression over the follow-up period (P < 0.0001). Importantly, there was a highly significant difference (P = 0.0004) in the rise in CD4 count between those with 2-3 log suppression (161 x 10(6) cells/l) and those with > 3 log suppression (314 x 10(6) cells/l; mean 3.6 log suppression in this group), suggesting that with even greater suppression the rise in CD4 lymphocytes may be still larger. We also studied whether CD4 counts were still rising after 72 weeks in patients with sustained suppression of at least 3 log in viral load. There was a significant (P = 0.004; paired t-test) rise in count of 43 x 10(6) cells/l between weeks 64 and 72 in these patients, suggesting that regeneration continues at least up to 72 weeks after therapy, provided virus replication continues to be suppressed. Patients with initial CD4 counts < 10 x 10(6) cells/l experienced no smaller rises than those at higher levels, even after adjustment for other factors. CONCLUSION These results strongly support a direct causal relationship between HIV replication and CD4 lymphocyte count depletion. The rise in those with > 3 log suppression provides the best available indicator of the potential for natural CD4 regeneration in HIV-infected patients. However, since still greater CD4 count rises may be seen with more suppressive regimens, it may not be possible to study the intrinsic CD4 regenerative capacity until such regimens are available.

End‐stage renal disease and dialysis in HIV‐positive patients: observations from a long‐term cohort study with a follow‐up of 22 years

Renal disease is a common and serious complication in HIV‐infected patients.

Use of viral load measured after 4 weeks of highly active antiretroviral therapy to predict virologic outcome at 24 weeks for HIV-1-positive individuals.

SummaryEarly prediction of suboptimal viral response to highly active antiretroviral therapy (HAART) is vital to prevent early development of drug resistance. We used logistic regression to predict the odds of achieving virologic suppression (<50 copies/mL) after 24 weeks of HAART in 656 antiretroviral-naive patients starting HAART at the J.W. Goethe University, Chelsea and Westminster, and Royal Free Hospitals according to their week 4 viral load. Therapy changes involving the switch of a single antiretroviral were assumed to have occurred for toxicity reasons and ignored. Because complete regimen changes or additions of new antiretrovirals could be due to virologic failure, patients were counted as virological failures at week 24. Three hundred sixty (84%) of 430 patients with viral loads of <1000 copies/mL, 106 (61%) of 175 with viral loads between 1001 and 10,000 copies/mL, 11 (37%) of 30 with viral loads between 10,001 and 100,000 copies/mL, and 5 (24%) of 21 with viral loads of >100,000 copies/mL at week 4 subsequently attained virologic suppression at 24 weeks. The odds of attaining virologic suppression at 24 weeks was 65% lower for every 1-log higher viral load at week 4 (odds ratio, 0.35; 95% confidence interval, 0.27–0.45). The proportion of patients with an undetectable viral load at 24 weeks among those who have not attained a viral load of <1000 copies/mL by 4 weeks is quite low. We suggest that this group of patients should be particularly closely monitored.

Long-term effects of chemoradiotherapy for anal cancer in patients with HIV infection: oncological outcomes, immunological status, and the clinical course of the HIV disease.

BACKGROUND: Despite the increasing evidence for chemoradiotherapy as standard treatment for anal cancer in patients with HIV infection, there is still some uncertainty regarding increased toxicity and adverse effects on the immune status. OBJECTIVE: We report the clinical outcome of 5-fluorouracil/mitomycin C-based concurrent chemoradiotherapy for anal carcinoma in patients with HIV infection with an emphasis on the long-term course of CD4 counts and the HIV-related morbidity during follow-up. DESIGN AND SETTINGS: A retrospective single-institution chart review was performed. PATIENTS: Between 1997 and 2012, 36 HIV-positive patients were treated with standard chemoradiotherapy (median tumor dose, 54 (range, 50.4–60.4) Gy at 1.8 Gy/fraction; 5-fluorouracil, 800–1000 mg/m2, days 1–4 or 1–5; mitomycin C, 10 mg/m2, day 1, in the first and fifth week). MAIN OUTCOME MEASURES: A retrospective analysis was performed with respect to tumor response, local control, cancer and overall survival, and toxicity. Immunological parameters, including pre- and posttreatment CD4 counts, viral load, and HIV-specific morbidity were recorded during follow-up. RESULTS: Chemoradiotherapy could be completed in all patients. Acute grade 3 toxicities occurred in 17/36 patients (47%). Complete response was achieved in 31 patients (86%). Five-year local control, colostomy-free, cancer-specific, and overall survival were 72%, 87%, 77%, and 74%. The median pretreatment CD4 count significantly decreased from 367 cells/&mgr;L to 139 cells/&mgr;L, 3 to 7 weeks after completion of chemoradiotherapy (p < 0.001). Four patients (11%) experienced opportunistic illnesses during the follow-up (median, 66; range, 10–164 months). LIMITATIONS: This study is limited by its retrospective design and its small sample size. CONCLUSIONS: Our data confirm again that, in the highly active antiretroviral therapy era, anal cancer can be treated in HIV-positive patients with standard chemoradiotherapy, with a clinical outcome similar to their HIV-negative counterparts. The chemoradiotherapy-related decline of the CD4 counts, which remain decreased up to 6 years after chemoradiotherapy, was not associated with increased HIV-related clinical morbidity.

Acute kidney injury caused by tenofovir disoproxil fumarate and diclofenac co-administration

The renal elimination of tenofovir (TFV) may be subject to renal drug−drug interactions that may increase the risk of kidney injury. Case reports indicated that diclofenac might increase TFV‐associated nephrotoxicity via a drug−drug interaction, leading to an increased intracellular TFV concentration in proximal tubular cells.

Assessment of liver fibrosis and associated risk factors in HIV-infected individuals using transient elastography and serum biomarkers

BackgroundLiver fibrosis in human immunodeficiency virus (HIV)-infected individuals is mostly attributable to co-infection with hepatitis B or C. The impact of other risk factors, including prolonged exposure to combined antiretroviral therapy (cART) is poorly understood. Our aim was to determine the prevalence of liver fibrosis and associated risk factors in HIV-infected individuals based on non-invasive fibrosis assessment using transient elastography (TE) and serum biomarkers (Fibrotest [FT]).MethodsIn 202 consecutive HIV-infected individuals (159 men; mean age 47 ± 9 years; 35 with hepatitis-C-virus [HCV] co-infection), TE and FT were performed. Repeat TE examinations were conducted 1 and 2 years after study inclusion.ResultsSignificant liver fibrosis was present in 16% and 29% of patients, respectively, when assessed by TE (≥ 7.1 kPa) and FT (> 0.48). A combination of TE and FT predicted significant fibrosis in 8% of all patients (31% in HIV/HCV co-infected and 3% in HIV mono-infected individuals). Chronic ALT, AST and γ-GT elevation was present in 29%, 20% and 51% of all cART-exposed patients and in 19%, 8% and 45.5% of HIV mono-infected individuals. Overall, factors independently associated with significant fibrosis as assessed by TE (OR, 95% CI) were co-infection with HCV (7.29, 1.95-27.34), chronic AST (6.58, 1.30-33.25) and γ-GT (5.17, 1.56-17.08) elevation and time on dideoxynucleoside therapy (1.01, 1.00-1.02). In 68 HIV mono-infected individuals who had repeat TE examinations, TE values did not differ significantly during a median follow-up time of 24 months (median intra-patient changes at last TE examination relative to baseline: -0.2 kPa, p = 0.20).ConclusionsChronic elevation of liver enzymes was observed in up to 45.5% of HIV mono-infected patients on cART. However, only a small subset had significant fibrosis as predicted by TE and FT. There was no evidence for fibrosis progression during follow-up TE examinations.

Platelet–leucocyte adhesion markers before and after the initiation of antiretroviral therapy with HIV protease inhibitors

INTRODUCTION Thromboembolic complications under antiretroviral therapy (ART) have been described in the past. In particular, the influence of protease inhibitors (PIs) on platelet activation and coagulation is currently under discussion. METHODS HIV-1-infected, PI-naive adults (n = 18) were investigated before and 4 weeks after the start of the ART, consisting either of boosted PI regimens (n = 13) plus reverse transcriptase inhibitors (RTIs) or a double PI regimen (n = 5) without RTI co-medication. Administered PIs were saquinavir (n = 15), lopinavir (n = 4), fosamprenavir (n = 2) and atazanavir (n = 2). Platelet CD62P, CD40L (%+ cells) and PAC-1 binding [mean fluorescence intensity (MFI)] as well as monocyte CD11b (MFI) and monocyte-associated CD41 (%+ cells and MFI) expression were assessed by flow cytometry with or without platelet stimulation. To investigate the influence of platelets on coagulation, the endogenous thrombin potential (ETP) [render fluorescence units (RFI)] was determined. RESULTS CD62P, PAC-1 binding and CD11b expression remained unchanged. In contrast, the mean+/-SD MFI of CD40L (from 18.2+/-9.0 to 25.5+/-10.4, P = 0.038) and CD41 (from 446.1+/-213.8 to 605.0+/-183.8, P = 0.010) as markers for increased platelet-leucocyte interaction increased significantly. The collagen-induced ETP time-to-peak was altered significantly from 23.8+/-11.4 to 17.0+/-4.2 min (P = 0.028), although the ETP RFI peak showed no evidence for increased procoagulatory capacity (47.1+/-18.6 to 57.3+/-19.9, P = 0.085). CONCLUSIONS Effects of the evaluated PI HIV therapy on platelet function assessed under field conditions seem to be minor, not affecting all investigated parameters. We found no evidence for increased platelet activation under PI-containing ART. However, CD41 as a marker for increased platelet-leucocyte interaction and CD40L, which can contribute to atherosclerosis, increased significantly.

Quadruple Nucleos(t)ide Reverse Transcriptase Inhibitors-Only Regimen of Tenofovir Plus Zidovudine/Lamivudine/Abacavir in Heavily Pre-Treated HIV-1 Infected Patients: Salvage Therapy or Backbone Only?

BACKGROUND We investigated the virologic and immunologic responses to a mono-class, nucleoside/nucleotide reverse transcriptase inhibitor - combination therapy consisting of tenofovir and zidovudine/lamivudine/abacavir in therapy experienced patients. METHODS Retrospective study of 122 patients. Primary analysis was performed at 48 weeks. Virologic response was defined as viral load levels less than 400 copies/ml. RESULTS About half of the patients had switched to tenofovir+ zidovudine/lamivudine/abacavir for simplification purposes or toxicity while the other half had experienced virologic failure. 80/122 (66%) responded. Median viral load decreased to 78 copies/ml at week 48; median CD4 count increased to 321 cells/mm(3). Of the 42 virologic failures, only 3 patients failed after week 24. 24/35 patients who had been on a non-suppressive zidovudine/lamivudine/abacavir-only regimen at baseline and added tenofovir to intensify, responded. 41/53 patients who switched from any nucleoside reverse transcriptase inhibitor-only regimen improved or maintained suppression. Genotypes were available for 85/122 patients. The only predictor of virologic failure was the combination 41L+210W+215Y/F mutational pattern. 16 of the patients who failed on tenofovir+ zidovudine/lamivudine/abacavir therapy selected new primary nucleoside reverse transcriptase inhibitor resistance mutations that they previously did not have. 48/85 (56%) patients with genotype tests had at least 3 (3-10; median 4) nucleoside reverse transcriptase inhibitor resistance-associated mutations in the past. CONCLUSIONS Patients heavily pre-treated with nucleoside analogues may show response to mono-class tenofovir+ zidovudine/lamivudine/abacavir therapy despite having a history of failure with nucleoside reverse transcriptase inhibitors. Lower baseline viral load, higher baseline CD4 count were significant predictors for response. Archived 41L+210W+215Y/F mutational pattern was significantly associated with non-response.

Comparison of Drug Resistance Scores for Tipranavir in Protease Inhibitor-Naïve Patients Infected with HIV-1 B and Non-B Subtypes

ABSTRACT Genotypes of samples from protease inhibitor-naïve patients in Frankfurts HIV Cohort were analyzed with five tipranavir resistance prediction algorithms. Mean scores were higher in non-B than in B subtypes. The proportion of non-B subtypes increased with increasing scores, except in weighted algorithms. Virtual and in vitro phenotype analyses of samples with increased scores showed no reduced tipranavir susceptibility. Current algorithms appear suboptimal for interpretation of resistance to tipranavir in non-B subtypes; increased scores might reflect algorithm bias rather than “natural resistance.”