Max Essex

Prevention of HIV-1 Infection with Early Antiretroviral Therapy

BACKGROUND Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. METHODS In nine countries, we enrolled 1763 couples in which one partner was HIV-1-positive and the other was HIV-1-negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1-infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1-related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1-negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death. RESULTS As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P=0.01). CONCLUSIONS The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 052 ClinicalTrials.gov number, NCT00074581.).

Barriers to Antiretroviral Adherence for Patients Living with HIV Infection and AIDS in Botswana

Background: Botswana has the highest rate of HIV infection in the world, estimated at 36% among the population aged 15‐49 years. To improve antiretroviral (ARV) treatment delivery, we conducted a cross‐sectional study of the social, cultural, and structural determinants of treatment adherence. Methods: We used both qualitative and quantitative research methodologies, including questionnaires and interviews with patients receiving ARV treatment and their health care providers to elicit principal barriers to adherence. Patient report and provider estimate of adherence (≥95% doses) were the primary outcomes. Results: One hundred nine patients and 60 health care providers were interviewed between January and July 2000; 54% of patients were adherent by self‐report, while 56% were adherent by provider assessment. Observed agreement between patients and providers was 68%. Principal barriers to adherence included financial constraints (44%), stigma (15%), travel/migration (10%), and side effects (9%). On the basis of logistic regression, if cost were removed as a barrier, adherence is predicted to increase from 54% to 74%. Conclusions: ARV adherence rates in this study were comparable with those seen in developed countries. As elsewhere, health care providers in Botswana were often unable to identify which patients adhere to their ARV regimens. The cost of ARV therapy was the most significant barrier to adherence.

Production of hepatitis B virus by a differentiated human hepatoma cell line after transfection with cloned circular HBV DNA

Closed-circular HBV DNA was introduced into cells of the established human hepatoma culture HepG2. The culture medium of one of 40 single-cell clones contained HBV surface antigen (HBsAg), core-related antigens (HBc/eAg), and HBV DNA sequences. HBV DNA and DNA polymerase activity were detected in particles resembling both nucleocapsids and complete virions (Dane particles). Intracellular integrated and extrachromosomal HBV DNA sequences were detected. Relaxed-circular and single-stranded forms of viral DNA were identified as likely replicative intermediates of the HBV genome. In conclusion, in vitro production of Dane-like particles by transformed human hepatocytes has been achieved. This model should be valuable as a cell culture system for studying virus replication and virus-host cell interactions.

SEROLOGICAL EVIDENCE FOR VIRUS RELATED TO SIMIAN T-LYMPHOTROPIC RETROVIRUS III IN RESIDENTS OF WEST AFRICA

Serological evidence is presented here suggesting that a virus closely related to simian T-lymphotropic virus type III (STLV-III) infects man in Senegal, west Africa, a region where AIDS or AIDS-related diseases have not yet been observed. 25 sera from Senegalese individuals that were positive for antibodies to HTLV-III by enzyme-linked immunosorbent assay were examined for antibodies to HTLV-III and STLV-III by western blotting. Sera from individuals originating from regions where AIDS has been reported, such as the United States and Burundi (central Africa), reacted best with antigens of HTLV-III, although antibodies that cross-reacted with STLV-III p24 were also detected. Conversely, sera originating from Senegalese people reacted better with STLV-III than with HTLV-III. This was exemplified by the absence of reactivity in sera from both monkeys and Senegalese people to p41, an antigen regularly detected by sera from antibody positive individuals originating from central Africa or from the United States. In contrast sera from central Africa or the United States did not react with p32, the putative envelope transmembrane protein of STLV-III that is regularly detected by sera from both monkeys and antibody-positive Senegalese people. These results suggest that certain healthy Senegalese people have been exposed to a virus that is more closely related to STLV-III than to HTLV-III. The existence and study of such virus variants potentially with differential pathogenicity may provide important information for the development of an AIDS virus vaccine.

Randomized trial of vitamin supplements in relation to transmission of HIV-1 through breastfeeding and early child mortality.

Background: HIV-1 transmission through breastfeeding is a global problem and has been associated with poor maternal micronutrient status. Methods: A total of 1078 HIV-infected pregnant women from Tanzania were randomly assigned to vitamin A or multivitamins excluding A from approximately 20 weeks’ gestation and throughout lactation. Results: Multivitamins excluding A had no effect on the total risk of HIV-1 transmission (RR 1.04, 95% CI 0.82–1.32, P = 0.76). Vitamin A increased the risk of transmission (RR 1.38, 95% CI 1.09–1.76, P = 0.009). Multivitamins were associated with non-statistically significant reductions in transmission through breastfeeding, and mortality by 24 months among those alive and not infected at 6 weeks. Multivitamins significantly reduced breastfeeding transmission in infants of mothers with low baseline lymphocyte counts (RR 0.37; 95% CI 0.16–0.85, P = 0.02) compared with infants of mothers with higher counts (RR 0.99, 95% CI 0.68–1.45, P = 0.97; P-for-interaction 0.03). Multivitamins also protected against transmission among mothers with a high erythrocyte sedimentation rate (P-for-interaction 0.06), low hemoglobin (P-for-interaction 0.06), and low birthweight babies (P-for-interaction 0.04). Multivitamins reduced death and prolonged HIV-free survival significantly among children born to women with low maternal immunological or nutritional status. Vitamin A alone increased breastfeeding transmission but had no effect on mortality by 24 months. Conclusion: Vitamin A increased the risk of HIV-1 transmission. Multivitamin (B, C, and E) supplementation of breastfeeding mothers reduced child mortality and HIV-1 transmission through breastfeeding among immunologically and nutritionally compromised women. The provision of these supplements to HIV-infected lactating women should be considered.

HIV-1 subtype C viruses rapidly develop K65R resistance to tenofovir in cell culture

Background:Genotypic diversity among HIV-1 subtypes and circulating recombinant forms (CRF) may lead to distinct pathways to drug resistance. This study evaluated subtype-related differences in the development of resistance in culture to tenofovir. Methods:Genotyping determined nucleotide diversity among subtypes. Representative subtype B, C, CRF1_AE, CRF2_AG, G, and HIV-2 isolates were selected for resistance to tenofovir, lamivudine and didanosine in cell culture. Phenotypic assays determined the effects of the K65R substitution in reverse transcriptase (RT) on drug susceptibility. Results:Subtype C isolates show unique polymorphisms in RT codons 64 (AAG→AAA), 65 (AAA→AAG), and 66 (AAA→AAG), absent in other subtypes. The K65R mutation (AAG→AGG) arose with tenofovir by week 12 in four subtype C selections. In contrast, no tenofovir resistance arose in four subtype B (> 34–74 weeks), one each of CRF2_AG and G (> 30–33 weeks), and three HIV-2 (> 27–28 weeks) selections. K65R appeared after 55 and 73 weeks in two CRF1_AE selections with tenofovir. In contrast, times to the appearance of M184V with lamivudine pressure (weeks 8–14) did not vary among subtypes. Selective didanosine pressure resulted in the appearance of M184V and L74V after 38 weeks in two of four subtype C selections. The K65R transitions in subtype C and other subtypes (AGG and AGA) conferred similar 6.5–10-fold resistance to tenofovir and five to 25-fold crossresistance to each of abacavir, lamivudine, and didanosine, while not affecting zidovudine susceptibility. Conclusion:Tenofovir -based regimens will need to be carefully monitored in subtype C infections for the possible selection of K65R.

Effects of early versus delayed initiation of antiretroviral treatment on clinical outcomes of HIV-1 infection: results from the phase 3 HPTN 052 randomised controlled trial

BACKGROUND Use of antiretroviral treatment for HIV-1 infection has decreased AIDS-related morbidity and mortality and prevents sexual transmission of HIV-1. However, the best time to initiate antiretroviral treatment to reduce progression of HIV-1 infection or non-AIDS clinical events is unknown. We reported previously that early antiretroviral treatment reduced HIV-1 transmission by 96%. We aimed to compare the effects of early and delayed initiation of antiretroviral treatment on clinical outcomes. METHODS The HPTN 052 trial is a randomised controlled trial done at 13 sites in nine countries. We enrolled HIV-1-serodiscordant couples to the study and randomly allocated them to either early or delayed antiretroviral treatment by use of permuted block randomisation, stratified by site. Random assignment was unblinded. The HIV-1-infected member of every couple initiated antiretroviral treatment either on entry into the study (early treatment group) or after a decline in CD4 count or with onset of an AIDS-related illness (delayed treatment group). Primary events were AIDS clinical events (WHO stage 4 HIV-1 disease, tuberculosis, and severe bacterial infections) and the following serious medical conditions unrelated to AIDS: serious cardiovascular or vascular disease, serious liver disease, end-stage renal disease, new-onset diabetes mellitus, and non-AIDS malignant disease. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00074581. FINDINGS 1763 people with HIV-1 infection and a serodiscordant partner were enrolled in the study; 886 were assigned early antiretroviral treatment and 877 to the delayed treatment group (two individuals were excluded from this group after randomisation). Median CD4 counts at randomisation were 442 (IQR 373-522) cells per μL in patients assigned to the early treatment group and 428 (357-522) cells per μL in those allocated delayed antiretroviral treatment. In the delayed group, antiretroviral treatment was initiated at a median CD4 count of 230 (IQR 197-249) cells per μL. Primary clinical events were reported in 57 individuals assigned to early treatment initiation versus 77 people allocated to delayed antiretroviral treatment (hazard ratio 0·73, 95% CI 0·52-1·03; p=0·074). New-onset AIDS events were recorded in 40 participants assigned to early antiretroviral treatment versus 61 allocated delayed initiation (0·64, 0·43-0·96; p=0·031), tuberculosis developed in 17 versus 34 patients, respectively (0·49, 0·28-0·89, p=0·018), and primary non-AIDS events were rare (12 in the early group vs nine with delayed treatment). In total, 498 primary and secondary outcomes occurred in the early treatment group (incidence 24·9 per 100 person-years, 95% CI 22·5-27·5) versus 585 in the delayed treatment group (29·2 per 100 person-years, 26·5-32·1; p=0·025). 26 people died, 11 who were allocated to early antiretroviral treatment and 15 who were assigned to the delayed treatment group. INTERPRETATION Early initiation of antiretroviral treatment delayed the time to AIDS events and decreased the incidence of primary and secondary outcomes. The clinical benefits recorded, combined with the striking reduction in HIV-1 transmission risk previously reported, provides strong support for earlier initiation of antiretroviral treatment. FUNDING US National Institute of Allergy and Infectious Diseases.

HTLV-III IN SYMPTOM-FREE SERONEGATIVE PERSONS

Of 96 patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex and healthy individuals at risk for AIDS, 4 had no detectable antibodies to viral proteins, though human T-cell leukaemia (lymphotropic) virus type III was isolated from their lymphocytes. 3 of these subjects were symptom-free and 1 had lymphadenopathy. All 4 were sexual partners of patients with AIDS or AIDS-related complex. The occurrence of seronegative but virus-positive persons without clinical symptoms suggests that assays other than those detecting antibody to virus, perhaps based on detection of viral antigens or immune complexes, may be required to identify all infected individuals.

EVIDENCE FOR HUMAN INFECTION WITH AN HTLV III/LAV-LIKE VIRUS IN CENTRAL AFRICA, 1959

An individual serum stored since 1959 from Central Africa has been demonstrated reactive against HTLV-III by ELISA Western blotting and by immunoprecipitation against HTLV-III as well as STLV-III. This serum was from a set of 1213 plasmas from various parts of Africa 818 dating from 1959. Because of the known high false positive rates on Abbott EIA in long-term frozen sera those found to be above the cutoff using the formula (mean of 3 negative serum controls plus 10% of the mean of 2 positive serum controls) x 3 were retested by immunofluorescence microscopy and Western blot enzymatic immunoassay. 1 serum taken from Central Africa in 1959 was positive by both tests. This plasma had an OD more than 7 x the cutoff value. It reacted strongly in immunofluorescence with infected H9 cells. Reactivity was detected by Western Blot against all major HTLV-III viral proteins and polypeptide 121. By immunoprecipitation it reacted with all major gag and env encoded proteins of HTLV-III and the gag encoded proteins of STLV-III-AGM. These results suggest that HTLV-III prevalence was low in 1959 but that at least 1 individual was exposed to a similar virus over 25 years ago in Central Africa.

Simplified strategy for detection of recombinant human immunodeficiency virus type 1 group M isolates by gag/env heteroduplex mobility assay

We developed a heteroduplex mobility assay in the gag gene (gag HMA) for the identification of group M subtypes A to H. The assay covers the region coding for amino acid 132 of p24 to amino acid 20 of p7 (according to human immunodeficiency virus type 1 [HIV-1] ELI, 460 bp). The gag HMA was compared with sequencing and phylogenetic analysis of an evaluation panel of 79 HIV-1 group M isolates isolated from infected individuals from different geographic regions. Application of gag HMA in combination with env HMA on 252 HIV-1- positive plasma samples from Bénin, Cameroon, Kenya, and Zambia revealed a high prevalence of a variety of intersubtype recombinants in Yaoundé, Cameroon (53.8%); Kisumu, Kenya (26.8%); and Cotonou, Bénin (41%); no recombinants were identified among the samples from Ndola, Zambia. The AG(IbNG) circulating recombinant form, as determined by gag HMA, was found to be the most common intersubtype recombinant in Yaoundé (39.4%) and Cotonou (38.5%). Using a one-tube reverse transcriptase PCR protocol, this gag HMA in combination with env HMA is a useful tool for rapidly monitoring the prevalence of the various genetic subtypes as well as of recombinants of HIV-1. Moreover, this technology can easily be applied in laboratories in developing countries.ABSTRACT We developed a heteroduplex mobility assay in the gaggene (gag HMA) for the identification of group M subtypes A to H. The assay covers the region coding for amino acid 132 of p24 to amino acid 20 of p7 (according to human immunodeficiency virus type 1 [HIV-1] ELI, 460 bp). Thegag HMA was compared with sequencing and phylogenetic analysis of an evaluation panel of 79 HIV-1 group M isolates isolated from infected individuals from different geographic regions. Application of gag HMA in combination with envHMA on 252 HIV-1- positive plasma samples from Bénin, Cameroon, Kenya, and Zambia revealed a high prevalence of a variety of intersubtype recombinants in Yaoundé, Cameroon (53.8%); Kisumu, Kenya (26.8%); and Cotonou, Bénin (41%); no recombinants were identified among the samples from Ndola, Zambia. The AGIbNG circulating recombinant form, as determined bygag HMA, was found to be the most common intersubtype recombinant in Yaoundé (39.4%) and Cotonou (38.5%). Using a one-tube reverse transcriptase PCR protocol, this gag HMA in combination with env HMA is a useful tool for rapidly monitoring the prevalence of the various genetic subtypes as well as of recombinants of HIV-1. Moreover, this technology can easily be applied in laboratories in developing countries.