Whole-Body 18F-FDG PET/CT Is Superior to CT as First-Line Diagnostic Imaging in Patients Referred with Serious Nonspecific Symptoms or Signs of Cancer: A Randomized Prospective Study of 200 Patients.

A fast-track pathway has been established in Denmark to investigate patients with serious nonspecific symptoms and signs of cancer (NSSC), who are not eligible to enter an organ-specific cancer program. The prevalence of cancer in this cohort is approximately 20%. The optimal screening strategy in patients with NSSC remains unknown. The aim of the study was to investigate whether 18F-FDG PET/CT was superior to CT as an initial imaging modality in patients with NSSC. In a randomized prospective trial, the imaging modalities were compared with regard to diagnostic performance. Methods: Two hundred patients were randomized 1:1 to whole-body 18F-FDG PET/CT or CT of the thorax and abdomen as the imaging modality. A tentative diagnosis was established after first-line imaging. The final referral diagnosis was adjudicated by the physician, when sufficient data were available. Results: One hundred ninety-seven patients were available for analysis because 3 patients withdrew consent before scanning. Thirty-nine (20%) patients were diagnosed with cancer, 10 (5%) with an infection, 15 (8%) with an autoimmune disease, and 76 (39%) with other diseases. In the remaining 57 patients (28%), no specific disease was found. 18F-FDG PET/CT had a higher specificity (96% vs. 85%; P = 0.028) and a higher accuracy (94% vs. 82%; P = 0.017) than CT. However, there were no statistically significant differences in sensitivity (83% vs. 70%) or negative predictive values (96% vs. 92%). No difference in days to final referral diagnosis according to randomization group could be shown (7.2 vs. 7.6 d). However, for the subgroups in which the imaging modality showed a suggestion of malignancy, there was a significant delay to final diagnosis in the CT group compared with the 18F-FDG PET/CT group (11.6 vs. 5.7 d; P = 0.02). Conclusion: Compared with CT, we found a higher diagnostic specificity and accuracy of 18F-FDG PET/CT for detecting cancer in patients with NSSC. 18F-FDG PET/CT should therefore be considered as first-line imaging in this group of patients.

Closed incision negative pressure therapy: international multidisciplinary consensus recommendations.

Surgical site occurrences (SSOs) affect up to or over 25% of patients undergoing operative procedures, with the subset of surgical site infections (SSIs) being the most common. Commercially available closed incision negative pressure therapy (ciNPT) may offer surgeons an additional option to manage clean, closed surgical incisions. We conducted an extensive literature search for studies describing ciNPT use and assembled a diverse panel of experts to create consensus recommendations for when using ciNPT may be appropriate. A literature search of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials using key words 'prevention', 'negative pressure wound therapy (NPWT)', 'active incisional management', 'incisional vacuum therapy', 'incisional NPWT', 'incisional wound VAC', 'closed incisional NPWT', 'wound infection', and 'SSIs' identified peer-reviewed studies published from 2000 to 2015. During a multidisciplinary consensus meeting, the 12 experts reviewed the literature, presented their own ciNPT experiences, identified risk factors for SSOs and developed comprehensive consensus recommendations. A total of 100 publications satisfied the search requirements for ciNPT use. A majority presented data supporting ciNPT use. Numerous publications reported SSI risk factors, with the most common including obesity (body mass index ≥30 kg/m2 ); diabetes mellitus; tobacco use; or prolonged surgical time. We recommend that the surgeon assess the individual patient's risk factors and surgical risks. Surgeons should consider using ciNPT for patients at high risk for developing SSOs or who are undergoing a high-risk procedure or a procedure that would have highly morbid consequences if an SSI occurred.

Effectiveness of antiretroviral therapy in individuals who for economic reasons were switched from a once-daily single-tablet regimen to a triple-tablet regimen.

BACKGROUND: To assess the impact on virological outcomes of a switch from branded single-tablet regimen (STR) including tenofovir, efavirenz, and emtricitabine (STR-TEE) to generic triple-tablet regimen (TTR), including tenofovir, efavirenz, and lamivudine (TTR-TEL), which was implemented on April 1, 2011 to obtain economic savings. METHODS AND FINDINGS: From the Capital Region of Denmark (covering two-thirds of the Danish HIV patients), we included combination antiretroviral therapy (cART)-naive patients who administered STR-TEE from April 1, 2010 to March 31, 2011 (n = 111) or TTR-TEL from April 1, 2011 to March 31, 2012 (n = 56) and cART-experienced HIV patients who were on STR-TEE from April 1, 2010 (n = 356) or were switched from STR-TEE to TTR-TEL after April 1, 2011 (n = 512). We estimated the fraction with detectable HIV-RNA, development of the 184V/I resistance mutations, and time to switch of cART. Approximately 96.2% of cART-experienced patients on STR-TEE were shifted to TTR-TEL after April 1, 2011. For the naive STR-TEE and TTR-TEL patients, the fractions with detectable HIV-RNA at week 48 were 7.0% and 8.3% and for the cART experienced 4.0% and 4.4%, respectively. The 184V/I resistance mutation was detected in 1 cART-experienced patient on TTR-TEL with virological failure. The risk of switch to a new cART regimen was slightly increased in the cART-experienced population (difference in 1-year risk: 1.5%; 95% confidence interval: -2.4% to 5.4%). CONCLUSIONS: In settings comparable with the Danish health care system, the estimated economic savings from a switch from STR-TEE to TTR-TEL can be realized with negligible short-term risk of adverse outcomes.

Risk of HIV or second syphilis infection in Danish men with newly acquired syphilis in the period 2000-2010.

OBJECTIVES: Risk of subsequent diagnosis of HIV in persons diagnosed with newly acquired syphilis, and syphilis in HIV-infected persons, are of interest as these infections are markers of unsafe sex. METHODS: From a nationwide register, all Danish men aged >16 years diagnosed with syphilis in the period 2000-2010 (n=1217) were identified, and subsequently data on HIV status was extracted from the Danish HIV Cohort Study. We used Kaplan-Meier analysis to estimate the 5-year risk of HIV and second syphilis infection, and Cox regression to determine incidence rate ratios (IRR). RESULTS: The 5-year risk of HIV diagnosis was 9.8% (95% CI 7.0% to 12.6%). Those with a second diagnosis of syphilis had a higher risk of being diagnosed with HIV (IRR=3.1, 95% CI 1.2 to 8.0). The 5-year risk for a second diagnosis of syphilis was 14.8% (95% CI 12.1% to 17.4%) and HIV-infected persons had a higher risk of a second syphilis diagnosis (IRR=4.0, 95% CI 2.8 to 5.9). Sixty-five percent of the persons were men having sex with men (MSM). Thirty-four percent of the HIV-infected persons had viral load >1000 copies/ml at time of syphilis diagnosis. CONCLUSIONS: The substantial risks of syphilis and HIV infection in men diagnosed with one of these sexually transmitted diseases indicate a high frequency of unsafe sex in the Danish MSM population. As one-third of the HIV-infected persons diagnosed with syphilis had high viral loads, our data support initiation of antiretroviral therapy in all HIV-infected MSM to reduce HIV transmission.

Correlation of increases in 1,25-dihydroxyvitamin D during vitamin D therapy with activation of CD4+ T lymphocytes in HIV-1-infected males.

BACKGROUND: In HIV-1-infected individuals, levels of CD4+ T lymphocytes are depleted and regulatory T-lymphocytes (Tregs) are elevated. In vitro studies have demonstrated effects of vitamin D on the growth and differentiation of these cells. We speculated whether supplementation with vitamin D could have an effect on CD4+ T lymphocytes or Tregs in HIV-1-infected males. METHODS: We conducted a placebo-controlled randomized study that ran for 16 weeks and included 61 HIV-1-infected males, of whom 51 completed the protocol. The participants were randomized to 1 of 3 daily treatments: (1) 0.5-1.0 µg calcitriol and 1200 IU (30 µg) cholecalciferol, (2) 1200 IU cholecalciferol, (3) placebo. Percentages of the following T-lymphocyte subsets were determined: naïve CD4+ and CD8+ cells, activated CD4+ and CD8+ cells, and CD3+CD4+CD25+CD127low Tregs. Furthermore 1,25-dihydroxyvitamin D, 25-hydroxyvitamin D, and parathyroid hormone were measured. RESULTS: No significant changes of the studied T-lymphocyte subsets occurred in the treatment groups compared to the placebo group. Increases in 1,25-dihydroxyvitamin D were associated with increases in activated CD4+ T lymphocytes (P = .001) and Tregs (P = .01) in adjusted models. Changes in parathyroid hormone correlated inversely with Tregs (P = .02). Smokers had higher levels of naïve CD4+ T lymphocytes (37% vs 25%;P = .01), naïve CD8+ T lymphocytes (28% vs 19%; P = .03), and Tregs (9% vs 7%; P = .03). CONCLUSION: Cholecalciferol and calcitriol administered during 16 weeks did not change the levels of T-lymphocyte fractions compared to placebo. However, increases in 1,25-dihydroxyvitamin D were associated with an expansion of activated CD4+ cells and Tregs.

Molecular phylogenetics of transmitted drug resistance in newly diagnosed HIV Type 1 individuals in Denmark: a nation-wide study.

Highly active antiretroviral treatment is compromised by viral resistance mutations. Transmitted drug resistance (TDR) is therefore monitored closely, but follow-up studies of these patients are limited. Virus from 1405 individuals diagnosed with HIV-1 in Denmark between 2001 and 2009 was analyzed for TDR, and molecular-epidemiological links and progression of the infection were described based on data from standardized questionnaires, the prospective Danish HIV Cohort Study, and by phylogenetic analysis. Eighty-five individuals were found to be infected with virus harboring mutations resulting in a prevalence of 6.1%, with no changes over time. The main resistance mutations were nucleoside reverse transcriptase inhibitor (NRTI) mutation 215 revertants, as well as nonnucleoside reverse transcriptase inhibitor (NNRTI) mutation 103N/S and protease inhibitor (PI) mutations 90M and 85V. Phylogenetic analysis confirmed 12 transmission chains involving 37 TDR individuals. Of these 21 were also documented epidemiologically. The virus included in the transmission chain carried similar resistance mutations to the TDR index case, whereas controls chains from index cases without TDR were generally without resistance mutations. We observed no difference in progression of the infection between individuals infected with TDR and individuals infected with wild-type HIV-1. The prevalence of TDR is low in Denmark and transmission of dual-drug-resistant HIV-1 is infrequent. The TDR isolates were shown to originate from local patients failing therapy.

Full-length characterization of A1/D intersubtype recombinant genomes from a therapy-induced HIV type 1 controller during acute infection and his noncontrolling partner.

To increase the understanding of mechanisms of HIV control we have genetically and immunologically characterized a full-length HIV-1 isolated from an acute infection in a rare case of undetectable viremia. The subject, a 43-year-old Danish white male (DK1), was diagnosed with acute HIV-1 infection after 1 year in Uganda. Following transient antiretroviral therapy DK1 maintained undetectable viral load for more than 10 years. His Ugandan wife (UG1) developed high viral load. HIV-1 sequences from both individuals were compared by bootscanning for recombination break points. Diversity plots and phylogenic trees were constructed and diversity and evolutionary distances were calculated. Intracellular IFN-gamma in CD8(+)CD3(+) T-lymphocyte reactions was investigated by intracellular flow cytometry (IC-FACS). Virus isolates from both patients were A1D intersubtype recombinants showing 98% sequence homology in shared regions. Four of seven crossover points were identical; however, the env gene from UG1 was subtype D, but A1 in DK1. Both viruses encoded proteins of the expected length and replicated equally well in vitro. DK1 and UG1 shared the HLA-A02 tissue type. HLA-A02-restricted CD8(+) T cell IFN-gamma IC-FACS response in DK1 was detected against only one (Pol(476)) of 23 conserved epitopes. Neutralizing antibodies were induced only to the homologous isolate. These results indicate an A1D intersubtype recombination or transmission of a minor variant. Transient early antiretroviral therapy may have induced full HIV-1 control in this individual mediated by a narrow specific cytotoxic T lymphocyte and neutralizing antibody response and/or other factors yet to be characterized.

Unmeasured confounding caused slightly better response to HAART within than outside a randomized controlled trial.

OBJECTIVE: To compare the outcome of highly active antiretroviral therapy (HAART) in HIV-infected patients initiating equivalent regimens within and outside a randomized controlled trial (RCT). STUDY DESIGN AND SETTING: The Danish Protease Inhibitor Study (DAPIS) was a national multicenter RCT comparing initial treatment with indinavir, ritonavir, or saquinavir/ritonavir during 96 weeks. From the Danish HIV Cohort Study we identified all patients initiating one of these protease-inhibitor-based HAART regimens: 425 patients within DAPIS and 677 outside the trial. We compared viral load, CD4 count response, and mortality. RESULTS: At weeks 96 and 240, trial participants were more likely than nonparticipants to have undetectable viral load (adjusted odds ratio [adOR] 1.28 [95% CI=0.94-1.74] and 1.70 [95% CI=1.16-2.50]) and a CD4 increase > or =100 cells/microl (adOR 1.37 [95% CI=1.03-1.82] and 1.53 [95% CI=1.04-2.25]). For antiretroviral-experienced, but not for antiretroviral-naïve patients, trial participants had a lower risk of death (mortality rate ratio [MRR]=0.46 [95% CI=0.27-0.77]) than nonparticipants. This effect was moderated in adjusted analyses (MRR=0.60 [0.33-1.07]). CONCLUSIONS: Compared to nontrial patients, trial participants had better response to HAART. The differences were small defying the notion that results obtained in RCTs are unachievable in routine clinical practice.

Predictors of virological outcome and safety in primary HIV type 1-infected patients initiating quadruple antiretroviral therapy: QUEST GW PROB3005.

BACKGROUND: Initiation of antiretroviral therapy during primary human immunodeficiency virus (HIV)-1 infection may confer long-term benefit. METHODS: After initiation of zidovudine, lamivudine, abacavir, and amprenavir therapy in patients in the QUEST cohort, predictors of virological outcome, virological and immunological changes, and adverse events were evaluated over 48 weeks. RESULTS: One hundred forty-eight patients started antiretroviral therapy during primary HIV-1 infection with < or =3 bands on Western Blot (median plasma HIV-1 RNA load, 5.4 log copies/mL; median CD4 cell count, 517 cells/mm(3)). By week 48, 36% of patients had stopped treatment or were lost to follow-up. Among the 115 patients receiving follow-up care at week 48 (102 of whom were receiving antiretroviral therapy), the median viral load decrease was -5.4 log copies/mL (interquartile range [IQR], -6.4 to -3.9 log copies/mL), and the median increase in CD4 cell count was 147 cells/mm(3) (IQR, -1 to 283 cells/mm(3)); 84.2% of patients had a viral load < or =50 copies/mL, and 44.7% of patients had a viral load < or =3 copies/mL. The median cell-associated RNA level decreased from 3.4 log copies/million PBMCs (IQR, 2.9-4.1 log copies/million PBMCs) to 0.8 log copies/million PBMCs (IQR, 0.5-1.4 log copies/million PBMCs), and the median cell-associated DNA level decreased from 2.8 log copies/million PBMCs (IQR, 2.4-3.0 log copies/million PBMCs) to 1.6 log copies/million PBMCs (IQR, 1.2-1.9 log copies/million PBMCs); 33.3% of patients had an undetectable RNA level, and 9.5% of patients had an undetectable cell-associated DNA level. The median CD8(+)/CD38(++) T cell count decreased from 459 cells/mm(3) (IQR, 208-974 cells/mm(3)) to 33 cells/mm(3) (IQR, 19-75 cells/mm(3)). Baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were independent inverse predictors for reaching a viral load < or =3 copies/mL. Eighty-three patients experienced a serious adverse event (median duration of an adverse event, 15 days).Conclusions. Initiation of antiretroviral therapy during primary HIV-1 infection was associated with very significant antiretroviral activity and a decrease in immune activation. Lower baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were predictive of achieving a viral load < or =3 copies/mL.

Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test.

BACKGROUND: Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened for the presence of latent TB using the QFT-IT test. We here report the results from the first patients screened. METHODS: On a routine basis the QFT-IT test was performed and the results from 590 HIV positive individuals consecutively tested are presented here. CD4 cell count and TB risk-factors were recorded from patient files. MAIN FINDINGS: 27/590(4.6%) of the individuals were QFT-IT test positive, indicating the presence of latent TB infection. Among QFT-IT positive patients, 78% had risk factors such as long-term residency in a TB high endemic area (OR:5.7), known TB exposure (OR:4.9) or previous TB disease (OR:4.9). The prevalence of latent TB in these groups were 13%, 16% and 19% respectively. There was a strong correlation between low CD4 T-cell count and a low mitogen response (P < 0.001;Spearman) and more patients with low CD4 cell count had indeterminate results. CONCLUSION: We found an overall prevalence of latent TB infection of 4.6% among the HIV positive individuals and a much higher prevalence of latent infection among those with a history of exposure (16%) and long term residency in a high endemic country (13%). The QFT-IT test may indeed be a useful test for HIV positive individuals, but in severely immunocompromised, the test may be impaired by T-cell anergy.

Syphilis and human immunodeficiency virus (HIV)-1 coinfection: influence on CD4 T-cell count, HIV-1 viral load, and treatment response.

OBJECTIVES: To assess the effect of human immunodeficiency virus (HIV)-1 and syphilis coinfection on HIV-ribonucleic acid (RNA) viral load, CD4 cell count, and the response in rapid plasmin reagin (RPR) to treatment of the syphilis infection. STUDY DESIGN: Cases of syphilis diagnosed during 1 year in HIV-infected patients in Copenhagen were included. HIV-RNA, CD4 cell counts, and RPR-serology were measured before, during, and after syphilis. RESULTS: Forty-one patients were included. CD4 cell count decreased significantly during infection in patients with primary and secondary stages of syphilis (mean 106 cells/mm, P = 0.03). Treatment of syphilis was associated with an increase in the CD4 cell count and a decrease in HIV-RNA in the overall group (mean 66 cells/mm and -0.261 RNA log10 copies/ml, P = 0.02 and 0.04). The serological response rates for 15 patients treated with penicillin and 25 treated with doxycycline were the same. CONCLUSION: Syphilis was associated with a decrease in CD4 cell counts and an increase in HIV-RNA levels that both improved after treatment of syphilis.

A randomized trial to evaluate continuation versus discontinuation of lamivudine in individuals failing a lamivudine-containing regimen: the COLATE trial.

BACKGROUND: Lamivudine (3TC) therapy can cause the emergence of M1841/V. Previous studies suggest a higher fidelity of the mutant reverse transcriptase and lower replication capacity of the mutant virus. No data exist from clinical comparative studies evaluating the benefit of M1841/V in patients receiving combination antiretroviral therapy (cART). METHODS: HIV-1-infected adults failing a 3TC-containing regimen were randomized to continue (On-3TC) or discontinue 3TC (Off-3TC) whilst receiving cART. The primary efficacy measure was the log10 average-area-under-the-curve-minus-baseline reduction in HIV RNA over 48 weeks. Cryopreserved plasma samples from patients with baseline and > or =1 follow-up sample with HIV RNA >500 copies/ml were sequenced for a nucleotide distances substudy. Evolutionary distances were compared between treatment arms and between viruses with and without M1841/V. RESULTS: The overall 48-week log10 HIV RNA change was -1.4 (95% CI: -1.6, -1.1) for On-3TC (n=65) and -1.5 (95% CI: -1.7, -1.2) for Off-3TC (n=66; P=0.51). No difference was seen in the magnitude of the CD4+ T-cell count increases (median increase: 87 vs 76 cells/ml for 3TC vs Off-3TC, respectively). Thirty-seven patients had baseline and follow-up sequencing. Overall, there were 1.2 (95% CI: -2.2, 4.6) more nucleotide substitutions from baseline for Off-3TC patients (P=0.50), and 10.7 (95% CI: 7.5, 14.0) fewer nucleotide changes in viruses containing M18411V (P<0.0001). CONCLUSION: This study found no added virological or immunological benefit of continuing 3TC in patients on cART harbouring M1841/V. Evolutionary distances from baseline were larger in viruses that did not contain M1841/V. More discernable benefits may be seen in patients with fewer drug options as potent cART may eclipse a benefit of M1841/V in COLATE.

Tenofovir treatment in an unselected cohort of highly antiretroviral experienced HIV positive patients.

The aim of the present study was to explore the treatment effect of tenofovir as implemented in clinical practice. Data are presented on 34 patients. 11 patients had tenofovir added to a stable anti-retroviral treatment (ART) and 23 patients had drugs other than tenofovir. CD4 counts, HIV-RNA levels and genotypic resistance were determined at baseline and after 3 and 6 months. After initiation of tenofovir treatment, a mean decrease in HIV-RNA for all 34 patients was observed (-0.43 log1o copies/ml (+/- 1.22) and -0.49 log10 copies/ml (+/- 1.36) after 3 and 6 months, respectively, (p = 0.045)). However, the effect of tenofovir on HIV-RNA in the group of patients who had tenofovir added to a stable ART was limited, and the decrease in HIV-RNA was significantly higher in patients who had drugs other than tenofovir changed as well (p = 0.004 and p = 0.03 after 3 and 6 months, respectively). After initiation of tenofovir treatment, no significant increases in CD4 count were observed. All new NRTI-associated mutations could be explained by the background treatment. In conclusion, we observed a significant decrease in HIV-RNA only when tenofovir was prescribed, in conjunction with other anti-retroviral drugs, to patients on a failing highly active antiretroviral drug regimen (HAART).

Low efficacy and high frequency of adverse events in a randomized trial of the triple nucleoside regimen abacavir, stavudine and didanosine.

BACKGROUND: Highly active antiretroviral therapy containing three nucleoside reverse transcriptase inhibitors has been somewhat successful, but the clinical efficacy is unclear. METHODS: Randomized, controlled, open-label trial of 180 antiretroviral drug-naive HIV-infected patients allocated to a regimen of abacavir, stavudine and didanosine (A/S/D, n = 60), ritonavir and saquinavir (R/S 400/400 mg twice daily; n = 60) or nelfinavir and nevirapine (N/N 1250/200 mg twice daily; n = 60); the latter two in combination with lamivudine and zidovudine. The primary endpoint was HIV plasma RNA < or = 20 copies/ml after 48 weeks. RESULTS: At baseline, the median CD4 cell count was 161 x 106 cells/l (range, 0-920) and the HIV RNA was 5.0 log10 copies/ml (range, 2.7-6.7). At 48 weeks, 43% in the A/S/D arm had a HIV RNA < or = 20 copies/ml, compared with 69% in the N/N arm (P < 0.01) and 62% in the R/S arm (P < 0.05). In a multivariate analysis, the A/S/D arm had an odds ratio of obtaining a viral load of < or = 20 copies/ml at week 48 of 0.25 [95% confidence interval (CI) 0.10-0.59] versus N/N and 0.53 (95% CI, 0.33-0.83) versus R/S. The A/S/D arm had a particularly poor outcome in patients with higher viral load and AIDS at baseline: 63% had to discontinue A/S/D (any drug). Side effects were more frequent in the A/S/D arm and included neuropathy 27%, suspicion of hypersensitivity 12%, and increase in lactate accompanied by systemic symptoms 8%. CONCLUSION: The A/S/D regimen had a low efficacy and a high frequency of adverse events and cannot be recommended.

Optimization and immune recognition of multiple novel conserved HLA-A2, human immunodeficiency virus type 1-specific CTL epitopes.

MHC-I-restricted cytotoxic responses are considered a critical component of protective immunity against viruses, including human immunodeficiency virus type 1 (HIV-1). CTLs directed against accessory and early regulatory HIV-1 proteins might be particularly effective; however, CTL epitopes in these proteins are rarely found. Novel artificial neural networks (ANNs) were used to quantitatively predict HLA-A2-binding CTL epitope peptides from publicly available full-length HIV-1 protein sequences. Epitopes were selected based on their novelty, predicted HLA-A2-binding affinity and conservation among HIV-1 strains. HLA-A2 binding was validated experimentally and binders were tested for their ability to induce CTL and IFN-gamma responses. About 69 % were immunogenic in HLA-A2 transgenic mice and 61 % were recognized by CD8(+) T-cells from 17 HLA-A2 HIV-1-positive patients. Thus, 31 novel conserved CTL epitopes were identified in eight HIV-1 proteins, including the first HLA-A2 minimal epitopes ever reported in the accessory and regulatory proteins Vif, Vpu and Rev. Interestingly, intermediate-binding peptides of low or no immunogenicity (i.e. subdominant epitopes) were found to be antigenic and more conserved. Such epitope peptides were anchor-optimized to improve immunogenicity and further increase the number of potential vaccine epitopes. About 67 % of anchor-optimized vaccine epitopes induced immune responses against the corresponding non-immunogenic naturally occurring epitopes. This study demonstrates the potency of ANNs for identifying putative virus CTL epitopes, and the new HIV-1 CTL epitopes identified should have significant implications for HIV-1 vaccine development. As a novel vaccine approach, it is proposed to increase the coverage of HIV variants by including multiple anchor-optimized variants of the more conserved subdominant epitopes.

K65R with and without S68: a new resistance profile in vivo detected in most patients failing abacavir, didanosine and stavudine.

Antiretroviral treatment with three nucleoside reverse transcriptase inhibitors (NRTIs) is widely used, but the combination of abacavir, didanosine and stavudine has never been investigated. We describe the surprising and consistent genotypic and phenotypic outcome in patients failing this combination. As part of a Danish multicentre study, 60 antiretroviral-naive patients were randomized to treatment with abacavir, didanosine and stavudine. Failure was defined as one HIV-1 RNA >400 copies/ml. Genotyping was performed using TrueGene HIV-1 assay (Visible Genetics, London, UK). Phenotypic susceptibilities were determined with the Virco Antivirogram assay. Eight patients failed treatment with a median viral load of 2.980 copies/ml (range 478-5.950). At baseline, five patients were wild-type. Three patients harboured nucleoside excision mutations (NEMs), but phenotypic susceptibilities were within normal range. All five patients with wild-type virus developed K65R and four of these patients also acquired the S68G mutation. Phenotypic susceptibility decreased towards abacavir (median 8.9-fold) and didanosine (median 3.2-fold), while susceptibility towards stavudine was unchanged (median 0.8-fold). Susceptibility towards lamivudine and tenofovir decreased median 14.2- and 4.0-fold, respectively. In two patients with baseline resistance mutations, further accumulation of NEMs and V75T or L74V was observed. One patient developed Q151M. Failure of a triple NRTI regimen is possible and frequent with only the K65R mutation. Under adequate selection pressure K65R can easily emerge in vivo and may compromise several future treatment options including newer NRTIs. The unexpected high incidence of S68G suggests a functional role of this mutation in viruses harbouring K65R.

Prevalence of drug resistance mutations and non-B subtypes in newly diagnosed HIV-1 patients in Denmark.

The aim of this study was to monitor the prevalence of drug resistance mutations in newly diagnosed HIV-1 positive individuals in Denmark. In addition we assessed the prevalence of non-B subtypes based on phylogenetic analysis of the pol gene. Plasma samples from 104 newly diagnosed HIV-1 positive patients were obtained in the year 2000. The entire protease gene and 320 amino acids of the reverse transcriptase gene were genotyped. Sequences were obtained from 97 patients. No subjects displayed primary resistance mutations in the protease gene, whereas all carried 1 or more secondary mutations. Resistance mutations in the RT-gene associated with NRTI-resistance were found in 1 patient, who was infected with zidovudine resistant HIV-1 harbouring the M41L mutation in combination with T215S and L210S. The T215S mutation has been showed to be associated with reversion of zidovudine resistance. The T215S mutation was found in 1 additional patient. The subtype distribution was subtype B 59%, C 18%, A 8%, CRF02_AG 5%, CRF01_AE 4%, D 3% and G 2%. We found 2 patients (2%) with mutations associated with resistance in the RT-gene and none in the protease gene indicating a low prevalence of resistant HIV-1 in Denmark in the year 2000.

A randomized trial comparing initial HAART regimens of nelfinavir/nevirapine and ritonavir/saquinavir in combination with two nucleoside reverse transcriptase inhibitors.

BACKGROUND: A triple-class HAART regimen may be associated with a better virological effect than conventional regimens, but may also lead to toxicity and more profound resistance. METHODS: Randomized, controlled, open-label trial of 233 protease inhibitor- and non-nucleoside reverse transcriptase inhibitor-naive HIV-infected patients allocated to a regimen of nelfinavir and nevirapine (1250/200 mg twice daily; n = 118) or ritonavir and saquinavir (400/400 mg twice daily; n = 115), both in combination with two nucleoside reverse transcriptase inhibitors. The primary end-point was HIV RNA < or = 20 copies/ml after 48 weeks (missing value = failure). Patients remained under follow-up also in case of switch from the randomized therapy. RESULTS: At baseline, the median CD4 cell counts were 126 (range: 0-942) (nelfinavir/nevirapine) and 150 (0-642) (ritonavir/saquinavir) cells/mm3, and HIV RNA measurements 5.0 copies/ml (1.3-6.4) in both groups. A total of 102 (86%) and 101 (88%) were antiretroviral-naive. 44% discontinued randomized therapy; P = 0.13. Of these, 80 and 73% switched therapy due to adverse events; P = 0.99. At week 48, 69 and 56%, respectively, had a HIV RNA < or = 20 copies/ml; P = 0.037. CONCLUSION: A regimen of nelfinavir/nevirapine had a favourable virological effect and tolerability over a 48-week period compared with ritonavir/saquinavir, when administered in combination with two nucleoside reverse transcriptase inhibitors. However, more extensive follow-up is required to determine the long-term consequences of triple class HAART regimens, including the development of broad drug resistance.