AIDS Clinical Trials Group Protocol Research Articles

Pharmacokinetic/Pharmacodynamic Modeling of the Antiretroviral Activity of the CCR5 Antagonist Vicriviroc in Treatment Experienced HIV-Infected Subjects (ACTG Protocol 5211)

This substudy of AIDS Clinical Trials Group (ACTG) Protocol 5211 explored the relationship between antiretroviral effect and plasma concentrations of vicriviroc, an investigational CCR5 antagonist for HIV infection. Eighty-six treatment-experienced subjects failing their current antiretroviral regimens were randomized to add vicriviroc 5, 10, or 15 mg once daily or placebo for 2 weeks. Beyond week 2, subjects were changed to optimized background antiretroviral treatment while continuing vicriviroc or placebo. Plasma samples collected at weeks 2 and 8 were assayed for vicriviroc concentrations and combined with vicriviroc concentration data from 110 seronegatives enrolled in 5 phase 1 studies. An inhibitory Emax model was used to assess pharmacokinetic (PK)/pharmacodynamic relationships and recursive partitioning was applied to determine the breakpoint in vicriviroc PK parameters associated with virologic suppression. A 2-compartment model was fitted to the drug concentration data. At week 2, a higher vicriviroc Cmin was associated with a greater mean drop in HIV RNA (viral load) and a higher percentage of subjects experiencing a >1 log10 copies/mL drop in viral load. In subjects with Cmin > 54 ng/mL, the mean viral load decrease was 1.35 log10 copies/mL vs. 0.76 log10 with Cmin < 54 ng/mL (P = 0.003, Student t test). At this Cmin breakpoint, 70% of subjects with the higher Cmin had a >1 log drop in HIV RNA, compared with 44% with a lower Cmin (P = 0.048, Fisher exact test). Similar results were seen with an area under the curve breakpoint of 1460 ng h/mL. At weeks 16 and 24, all vicriviroc-treated subjects experienced better viral load responses than placebo recipients, but there was no apparent relationship between PK and change in viral load among these vicriviroc-treated subjects. There was a positive correlation between vicriviroc Cmin, area under the curve, and viral load changes at week 2 in treatment-experienced HIV-infected subjects receiving no other new active antiretroviral drugs. This correlation did not persist beyond week 16, probably because treatment response at that point also depended on having other active drugs in the regimen.

Measurement of Antiretroviral Drugs in the Lungs of HIV-Infected Patients

AIMS: Prior studies have shown that HAART is associated with decreased HIV viral load in the lungs. The correlation between antiretroviral exposure in bronchoalveolar lavage (BAL) fluid and virologic response was evaluated in patients starting HAART and enrolled in The AIDS Clinical Trial Group Protocol 723. MATERIALS #ENTITYSTARTX00026; METHODS: A total of 24 subjects underwent blood and BAL sampling prior to starting HAART, and after 4 and 24 weeks of HAART. Drug concentrations and HIV RNA were measured in paired plasma and BAL samples. RESULTS: Antiretroviral drugs, including efavirenz, were detectable in BAL fluid of HIV-infected subjects beginning HAART. Efavirenz was also associated with a higher likelihood of clearing HIV RNA from the lungs. CONCLUSION: These results suggest the excellent pulmonary virologic response to antiretroviral therapy may, in part, be due to penetration of antiretroviral drugs into the alveolar compartment.

Pre‐existing Minority Drug‐Resistant HIV‐1 Variants, Adherence, and Risk of Antiretroviral Treatment Failure

The clinical relevance of detecting minority drug-resistant human immunodeficiency virus type 1 (HIV-1) variants is uncertain. To determine the effect of pre-existing minority nonnucleoside reverse-transcriptase inhibitor (NNRTI)-resistant variants on the risk of virologic failure, we reanalyzed a case-cohort substudy of efavirenz recipients in AIDS Clinical Trials Group protocol A5095. Minority K103N or Y181C populations were determined by allele-specific polymerase chain reaction in subjects without NNRTI resistance by population sequencing. Weighted Cox proportional hazards models adjusted for recent treatment adherence estimated the relative risk of virologic failure in the presence of NNRTI-resistant minority variants. The evaluable case-cohort sample included 195 subjects from the randomly selected subcohort (51 with virologic failure, 144 without virologic failure), plus 127 of the remaining subjects who experienced virologic failure. Presence of minority K103N or Y181C mutations, or both, was detected in 8 (4.4%), 54 (29.5%), and 11 (6%), respectively, of 183 evaluable subjects in the random subcohort. Detection of minority Y181C mutants was associated with an increased risk of virologic failure in the setting of recent treatment adherence (hazard ratio, 3.45 [95% confidence interval, 1.90-6.26]) but not in nonadherent subjects (hazard ratio, 1.39 [95% confidence interval, 0.58-3.29]). Of note, 70% of subjects with minority Y181C variants achieved long-term viral suppression. In adherent patients, pre-existing minority Y181C mutants more than tripled the risk of virologic failure of first-line efavirenz-based antiretroviral therapy. NCT00013520.

Potential Confounding of the Association Between Exposure to Nucleoside Analogues and Mitochondrial Dysfunction in HIV-Uninfected and Indeterminate Infants

Potential Confounding of the Association Between Exposure to Nucleoside Analogues and Mitochondrial Dysfunction in HIV-Uninfected and Indeterminate Infants

Selegiline and oxidative stress in HIV-associated cognitive impairment

To assess the effectiveness of the selegiline transdermal system (STS) in reversing HIV-induced metabolic brain injury (as measured by proton magnetic resonance spectroscopy [MRS]) and in decreasing oxidative stress, measured by CSF protein carbonyl concentration. Sixty-two subjects with HIV-associated cognitive impairment were coenrolled in a 24-week placebo-controlled study (AIDS Clinical Trial Group protocol A5090) and were randomly assigned to receive STS 3 mg/24 h, STS 6 mg/24 h, or matching placebo. Cognitive performance was evaluated using the neuropsychological z score (NPZ)-8 and NPZ-6, as well as cognitive domain scores. Subjects underwent proton MRS at study entry and weeks 12 and 24. CSF protein carbonyl was measured at baseline and week 24. A slight increase in N-acetyl aspartate/creatine from baseline to week 24 was found in the basal ganglia (p = 0.023) and centrum semiovale (p = 0.072) of the placebo group compared with the STS groups; however, there were no significant changes when the absolute metabolite concentrations were analyzed. The levels of choline/creatine in the midfrontal cortex were also significantly higher during the week 12 visit in the combined STS groups. This persisted to the week 24 visit (p = 0.002). Evaluation of the change in NPZ-8, NPZ-6, and cognitive domain scores from baseline to weeks 12 and 24 revealed no significant differences between treatment arms. Protein carbonyl analysis revealed no significant changes among the groups. In this 24-week study, the selegiline transdermal system (STS) had no effect on either magnetic resonance spectroscopy (MRS) metabolites or oxidative stress, as measured by CSF protein carbonyl concentration. The lack of effect on these biomarkers is also reflected in the lack of cognitive improvement in the STS groups compared to placebo. This study provides Class II evidence that STS had no effect on either MRS metabolites or oxidative stress, as measured by CSF protein carbonyl concentration over a period of 24 weeks.

Human Immunodeficiency Virus Diagnostic Testing of Infants at Clinical Sites in North America

Our objectives were to assess the timing of testing, the types of diagnostic assays used, and the costs associated with the diagnosis of HIV-1 infection among infants born to HIV-1-infected women enrolled in the International Maternal Pediatric Adolescent AIDS Clinical Trials Group Protocol 1025 (P1025). P1025 is a prospective cohort study of HIV-1-infected women and their infants at clinical sites in the United States and Puerto Rico. Enrollment began in 2002 and is ongoing. Follow-up of infants continued for at least 6 months after delivery/birth. The study population for this analysis comprised all live born infants of known HIV-1 infection status, born by December 31, 2006 to enrolled women. Nine hundred eighty-eight infants had 5147 HIV-1 diagnostic test results reported. The median number of HIV-1 diagnostic assays performed per infant was 5 (10th, 90th percentiles: 3, 7), and the greatest number of tests reported per infant was 13. The median ages at the time of the first, second, third, and fourth HIV-1 diagnostic assay were 0.1, 2.3, 7.0, and 17.6 weeks, respectively. Nucleic acid amplification tests (NAATs) represented 86.9% of all diagnostic assays (HIV-1 DNA PCR assays: n = 4082 [79.3%]; other NAATs: n = 389 [7.6%]). The median cost per infant for HIV-1 diagnostic testing was $1168 (10th, 90th percentiles: $762, $1642). Most assays reported for HIV-1-exposed infants at clinical sites in the United States and Puerto Rico were NAATs, but the number of HIV-1 diagnostic assays performed per infant, and the cost associated with HIV-1 diagnostic testing per infant, varied greatly.

Repeat Pregnancies Among HIV-Infected Women Enrolled in Clinical Trial PACTG1022

We evaluated the rate and potential predictors of repeat pregnancy during 2 years of postpartum follow-up among women enrolled to a clinical trial that compared 2 initial antiretroviral regimens in pregnancy. These women had intensive follow-up during and after pregnancy including extensive contraceptive counseling and were specifically counseled to avoid subsequent pregnancies on study. We hypothesized that occurrence of repeat pregnancies might be predicted by specific demographic and/or clinical characteristics. By identifying these characteristics we hoped to target HIV-infected women most at risk for repeat pregnancy with more focused contraceptive counseling. (excerpt)

Lymphoma Diagnosis and Plasma Epstein‐Barr Virus Load during Vicriviroc Therapy: Results of the AIDS Clinical Trials Group A5211

Lack of functional CCR5 increases the severity of certain viral infections, including West Nile virus and tickborne encephalitis. In a phase II trial of the investigational CCR5 antagonist vicriviroc (AIDS Clinical Trials Group protocol A5211), 4 lymphomas occurred in study patients who received vicriviroc. Because of the known association between unregulated Epstein-Barr virus (EBV) replication and lymphoma in immunocompromised patients, we evaluated whether vicriviroc exposure was associated with lymphoma EBV antigen positivity and/or had an effect on plasma levels of EBV DNA. Clinical findings for all 4 patients enrolled in the A5211 study who developed lymphoma (2 Hodgkin and 2 non-Hodgkin) were reviewed, and tumor specimens were assessed for evidence of ongoing EBV replication. Longitudinal plasma samples from 116 patients in the A5211 study were analyzed, and EBV DNA was quantified by real-time polymerase chain reaction. Plasma EBV DNA was not detected in the 2 patients with non-Hodgkin lymphoma; both patients with Hodgkin lymphoma who had samples tested had EBV DNA levels <3200 copies/mL. One patient with Hodgkin lymphoma had a lymph node core biopsy specimen that was strongly positive for EBV; the other 3 lymphomas were histochemically EBV negative. None of the 116 patients with available samples experienced sustained increases in plasma EBV levels. CCR5 antagonism by vicriviroc treatment in treatment-experienced patients was not associated with reactivation of EBV infection.

Incomplete reconstitution of T cell subsets on combination antiretroviral therapy in the AIDS Clinical Trials Group protocol 384.

Initiation of combination antiretroviral therapy (ART) results in higher total CD4 cell counts, a surrogate for immune reconstitution. Whether the baseline CD4 cell count affects reconstitution of immune cell subsets has not been well characterized. Using data from 978 patients (621 with comprehensive immunological assessments) from the AIDS [Acquired Immunodeficiency Syndrome] Clinical Trials Group protocol 384, a randomized trial of initial ART, we compared reconstitution of CD4(+), CD4(+) naive and memory, CD4(+) activation, CD8(+), CD8(+) activation, B, and natural killer cells among patients in different baseline CD4(+) strata. Reference ranges for T cell populations in control patients negative for human immunodeficiency virus (HIV) infection were calculated using data from AIDS Clinical Trials Group protocol A5113. Patients in the lower baseline CD4(+) strata did not achieve total CD4(+) cell counts similar to those of patients in the higher strata during 144 weeks of ART, although CD4(+) cell count increases were similar. Ratios of CD4(+) naive-memory cell counts and CD4(+):CD8(+) cell counts remained significantly reduced in patients with lower baseline CD4(+) cell counts (<or=350 cells/mm(3)). These immune imbalances were most notable for those initiating ART with a baseline CD4(+) cell count <or=200 cells/mm(3), even after adjustment for baseline plasma HIV RNA levels. After nearly 3 years of ART, T cell subsets in patients with baseline CD4(+) cell counts >350 cells/mm(3) achieved or approached the reference range those of control individuals without HIV infection. In contrast, patients who began ART with <or=350 CD4(+) cells/mm(3) generally did not regain normal CD4(+) naive-memory cell ratios. These results support current guidelines to start ART at a threshold of 350 cells/mm(3) and suggest that there may be immunological benefits associated with initiating therapy at even higher CD4(+) cell counts.

Development of a Directly Observed Therapy Adherence Intervention for Adolescents with Human Immunodeficiency Virus–1: Application of Focus Group Methodology to Inform Design, Feasibility, and Acceptability

PurposeTo obtain input from adolescents with human immunodeficiency virus–1 (HIV-1) infection to inform the design of a community-based modified directly observed therapy (MDOT) antiretroviral adherence intervention. MethodsPediatric AIDS Clinical Trials Group (PACTG) protocol 1036A conducted three focus groups with 17 adolescents aged 17–22 years (10 female, 65% African-American) from three geographically distinct US PACTG sites. Focus group sessions were scripted, audio-taped, and transcribed verbatim. A coding dictionary was developed and validated; Ethnograph version 5.08 was used to summarize coded data across and within the three sites. Prevalent themes were identified via frequencies and are reported as percentages. ResultsAdolescents provided the following specific input: the MDOT provider should be familiar with the participant and empathic; the MDOT location should be mutually agreed on, flexible, and private; and participant and provider communication should be bidirectional, preferably by phone. Ideally the MDOT program should be continued until adolescents independently demonstrate adherence and should include a weaning phase as a test of skill acquisition. The most commonly endorsed barrier to the proposed program was that MDOT would be an invasion of privacy. Initially, after introduction to the purpose of the focus group, all but one adolescent expressed the belief that MDOT could benefit persons other than themselves; however, at the conclusion of the focus group discussion, a significant shift in openness to the intervention occurred, in that 11 participants indicated they would consider participation in an MDOT program if such a program were offered. ConclusionsFocus group feedback clarified the feasibility, logistics, and patient concerns about the design and implementation of a proposed MDOT intervention for adolescents with HIV-1 infection who struggle with medication adherence.

Allocation of Family Responsibility for Illness Management in Pediatric HIV

The purpose of the study is to describe allocation of responsibility for illness management in families of children and adolescents perinatally infected with HIV. A total of 123 youth (ages 8-18) and caregivers completed family responsibility and medication adherence questionnaires as part of a substudy of Pediatric AIDS Clinical Trials Group protocol 219c. Approximately one-fourth of the youth reported being fully responsible for taking medications. A smaller percentage of caregivers reported full youth responsibility. Older youth and caregivers of older youth reported higher degree of youth responsibility for medication-related tasks, though age was unrelated to adherence. Caregiver report of greater responsibility for medications was associated with better adherence. Caregivers are likely to transition responsibility for HIV care to older youth but this transition was not always successful as evidenced by poor medication adherence. Interventions supporting successful transition may improve adherence and subsequently health outcomes in pediatric HIV.

Cord Blood Lipids in Infants Born to HIV-1-Infected Women Treated with Combination Antiretroviral Therapy

To investigate the effect of exposure to protease inhibitor (PI) therapy in utero on cord blood lipids in infants born to mothers enrolled in AIDS Clinical Trials Group protocol 5084, a prospective, multicentre, observational study of antiretroviral therapy (ART) during pregnancy. Clinical outcome was determined in 80 infants born to women treated with PIs and 73 infants born to women treated with other antiretrovirals during pregnancy. Cord blood serum from 117 of these infants was assayed for total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, triglyceride, apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB) and lipoprotein (a). Covariates considered in the analysis included race/ethnicity, gestational age, infant gender, infant birth weight, mode of delivery, maternal tobacco and alcohol use, post-partum body mass index, and ART duration. Cord blood total and HDL cholesterol, triglyceride, apoA1, apoB, lipoprotein (a) and apoB/apoA1 ratio were not different between the two groups. Cord blood lipid levels in these HIV-exposed infants were similar to those reported in other neonatal cohorts. Controlling for race/ethnicity, infants born to women treated with PIs had higher LDL cholesterol than those born to women not treated with PIs (29 mg/dl versus 27 mg/dl, P = 0.006). Only LDL cholesterol was significantly higher in the cord blood of PI-exposed infants versus those not exposed to PIs in utero. As the difference between the two groups was small, the clinical relevance of the effect of maternal PI treatment on infant LDL cholesterol levels at birth is not clear.

Pharmacokinetics and Safety of Nelfinavir When Used in Combination with Zidovudine and Lamivudine in HIV-Infected Pregnant Women: Pediatric AIDS Clinical Trials Group (PACTG) Protocol 353

Background: Combination antiretroviral regimens including nelfinavir (NFV) are commonly used in pregnancy. We studied the safety, antiviral effect, and pharmacokinetics of NFV and its M8 metabolite with two dosing regimens in combination with zidovudine (ZDV) and lamivudine (3TC) in HIV-infected pregnant women. Method: HIV-infected pregnant women between 14 and 34 weeks gestation received NFV (Cohort 1: 750 mg tid, n = 10; Cohort 2: 1250 mg bid, n = 23) with ZDV and 3TC. Serial blood sampling for NFV concentrations was performed antepartum (AP) and 6 weeks postpartum (PP). Maternal and cord blood samples were also obtained at delivery. NFV and M8 levels were determined by high-performance liquid chromatography. The pharmacokinetic (PK) target was an extrapolated NFV AUC_0–24 > 30 μg · h/mL. Mothers were followed frequently for potential clinical and laboratory toxicity. Results: Overall, NFV in combination with ZDV and 3TC was well tolerated. The PK target was met in 3/8 AP and 5/7 PP in Cohort 1 and 17/21 AP and 16/17 PP in Cohort 2. When Cohort 2 NFV PK parameters AP and PP were compared, median C_max (3.90 μg/mL vs. 5.01 μg/mL, p < .05) and AUC_0-24 (56.6 vs. 86.8 μg · h/mL, p < .05) were increased PP and oral clearance (Cl/F; 44.2 vs. 28.8 L/h, p < .05) was decreased PP. The average M8/NFV ratio was increased PP compared to AP (0.085 vs. 0.29, p < .001). Placental transfer of NFV was low with a median cord blood:maternal plasma ratio at delivery of 0.05. Maternal mean CD4+ T cell counts increased significantly and plasma HIV-1 RNA levels decreased from entry to delivery and 6 to 12 weeks postpartum. Conclusion: NFV used in combination with ZDV and 3TC was well tolerated in pregnant HIV-infected women and produced a significant improvement in HIV disease parameters. NFV drug exposure is inadequate in most pregnant women receiving 750 mg tid but is much improved with 1250 mg bid. NFV crosses the placenta poorly. The AP increase in NFV oral clearance and decrease in M8/NFV ratio suggest that CYP3A activity increases relative to CYP2C19 activity during pregnancy.

Effect of Highly Active Antiretroviral Therapy on Viral Burden in the Lungs of HIV‐Infected Subjects

Human immunodeficiency virus (HIV) is readily detectable in the lungs of infected subjects and leads to an accumulation of CD8(+) lymphocytes in the alveolar space. Although highly active antiretroviral therapy (HAART) is effective in reducing viremia, less is known about its effect on tissue compartments. The AIDS Clinical Trials Group Protocol 723 Team evaluated the effect of HAART on lung viral load and cellular constituents. Bronchoalveolar lavage (BAL) fluid and blood were collected before initiation of HAART and again at 4 and 24 weeks after initiation of therapy. The BAL cell differential was determined, lymphocyte phenotyping was performed, and acellular BAL fluid, plasma HIV RNA load, and BAL cell and peripheral blood mononuclear cell HIV RNA and DNA loads were measured. HAART induced a rapid decrease in HIV that was detectable in acellular BAL fluid and a slower decrease in the HIV RNA and DNA loads in BAL cells. HAART was associated with a significant decrease in the absolute number and percentage of CD8(+) alveolar lymphocytes. There was a significant correlation between residual BAL cell DNA at 24 weeks and the absolute number of CD4(+) lymphocytes in the alveolar space. HAART is associated with a significant decrease in the pulmonary HIV burden and a return of alveolar cellular constituents to normal.

Long-term Safety and Efficacy of a Once-Daily Regimen of Emtricitabine, Didanosine, and Efavirenz in HIV-Infected, Therapy-Naive Children and Adolescents: Pediatric AIDS Clinical Trials Group Protocol P1021

Compliance with complex antiretroviral therapy regimens is a problem for HIV-1-infected children and their families. Simple, safe, and effective regimens are important for long-term therapeutic success. A novel, once-daily dosing regimen of 3 antiretroviral drugs, emtricitabine, didanosine, and efavirenz, was tested in 37 therapy-naive HIV-infected children and adolescents between 3 and 21 years of age (inclusive). Subjects were followed for > or = 96 weeks on an intention-to-treat basis. Signs, symptoms, plasma HIV-1 RNA viral load, CD4 counts, and safety laboratories were followed regularly. End points were the proportion of subjects with plasma HIV < 400 or 50 HIV copies per mL and safety and tolerability of the regimen. Thirty-seven subjects enrolled at 16 sites. Two subjects with rashes during the first 2 weeks of therapy were the only adverse events leading to study-drug discontinuation. Other early (before protocol-scheduled conclusion) study discontinuations included 3 viral failures on treatment and 5 patients who stopped therapy for apparently nonmedical reasons. Possible drug-related adverse events included 1 grade 4 low-glucose and 5 varied grade 3 events. There were no deaths. Virologic outcomes demonstrated that 32 (85%) of 37 subjects achieved viral suppression to < 400 RNA copies per mL, and 26 (72%) of 37 subjects maintained sustained suppression at < 50 copies per mL through week 96. The median baseline CD4 count was 310 per microL (17%), which increased at week 96 by a median of +329 cells per microL (by +18% CD4). Pharmacokinetic results were as predicted for emtricitabine, didanosine, and efavirenz capsules, whereas efavirenz concentrations in children receiving efavirenz oral solution were lower than anticipated, requiring a dose escalation after the planned assessment point. A once-daily regimen of emtricitabine, didanosine, and efavirenz proved to be safe and tolerable and demonstrated good immunologic and virologic efficacy in this 2-year study.

Educational attainment and response to HAART during initial therapy for HIV-1 infection

Objective Previous research has demonstrated an association between educational attainment (EA) and negative physical and psychological outcomes. This study investigated whether EA is associated with regimen failure during initial therapy with highly active antiretroviral treatment (HAART) and whether adherence self-efficacy (ASE), a coping resource, moderates the relationship between EA and regimen failure. Methods A secondary analysis of AIDS Clinical Trial Group Protocol 384, an international, multicenter, randomized, partially double-blinded trial, included 799 male and 181 female antiretroviral-naïve subjects (age, 37.0±9.5 years). Participants were recruited from 1998 to 1999 and followed for a median of 2.3 years across 81 centers. The dependent variable was “time to first regimen failure.” Covariates include baseline HIV-1 log 10RNA and CD4 + counts, self-reported adherence, study site, ASE, age, sex, race, treatment assignment, and baseline use of nonantiretroviral medications. Results ASE significantly moderated the relationship between EA and regimen failure. Results showed that for every 10-unit increase in ASE, individuals with “less than high school” education had a 17% reduction in regimen failure (hazard ratio=0.83; 95% confidence interval=0.70–0.98) when compared to the reference group “college/graduate,” even after adjusting for baseline factors known to contribute to regimen failure. The time to first regimen failure was shorter with decreasing EA, trending toward significance ( P=.08). Conclusions There is a social gradient in HAART effectiveness, and ASE reduces the deleterious effects of lower EA on regimen failure. We recommend designing controlled interventions to evaluate the effectiveness of programs that increase ASE prior to initiation with HAART, particularly for those with lower EA.

In utero nucleoside reverse transcriptase inhibitor exposure and signs of possible mitochondrial dysfunction in HIV-uninfected children

There is equivocal evidence of in utero nucleoside reverse transcriptase inhibitor (NRTI) exposure and the occurrence of mitochondrial dysfunction (MD) in HIV-uninfected children born of HIV-infected women. The primary analysis included 1037 HIV-uninfected children born in 1991-2002 and enrolled in Pediatric AIDS Clinical Trials Group protocols 219/219C. Possible cases with unexplained signs of MD according to the Enquête Périnatale Française criteria were identified through retrospective review. Associations between overall in utero NRTI exposure, and trimester of first in utero NRTI exposure and possible MD were estimated with exact logistic regression. Cases (n = 20) were significantly more likely to be male and to be born in earlier years than non-cases (n = 1017). There was no association between overall in utero NRTI exposure and MD. In unadjusted models there were higher odds of first in utero exposure in the third trimester to lamivudine (3TC) [odds ratio (OR), 3.76 versus 3TC unexposed; 95% confidence interval (CI), 1.09-11.78] and to zidovudine (ZDV) and 3TC in combination (ZDV/3TC) (OR, 3.29 vs. ZDV/3TC unexposed; 95% CI, 0.96-10.25) among cases than noncases. When adjusted for year of birth the odds of first exposure in the third trimester to 3TC (OR, 10.57; 95% CI, 1.93-75.61) and ZDV/3TC (OR, 9.84; 95% CI, 1.77-71.68) were significantly higher among cases than non-cases. Incomplete data precluded control of possible confounding by maternal viral load and psychoactive drug use. Our study suggests that first exposure to 3TC or ZDV/3TC in the third trimester may be associated with the occurrence of possible MD. Further studies that rigorously assess MD and better control confounding are needed.

Reproductive Health of Adolescent Girls Perinatally Infected With HIV

We sought to describe the reproductive health of adolescent girls perinatally infected with HIV. We estimated the incidence of first pregnancy, genital infections, and abnormal cervical cytology for 638 girls aged 13 years and older in the Pediatric AIDS Clinical Trials Group protocol 219C. Thirty-eight girls became pregnant, for a first pregnancy rate of 18.8/1000 person-years; 7 of these girls had additional pregnancies (95% confidence interval [CI]=13.3, 25.7). Thirty-two pregnancies resulted in live births. All girls received antiretroviral therapy during pregnancy. One infant was HIV infected, 29 were uninfected, and 2 had unknown infection status, for a rate of mother-to-child transmission of HIV in infants with known infection status of 3.3% (95% CI=0.1, 18.6). Condylomata and trichomoniasis were the most frequent genital infections. Forty-eight (47.5%) of 101 girls with Papanicolaou test examinations had abnormal cervical cytology, including atypical cells of undetermined significance (n=18), low-grade squamous intraepithelial lesions (SIL; n=27), and high-grade SIL (n=3). Many abnormalities persisted despite intervention. Pregnancy rates were lower and cervical abnormalities were higher than among non-HIV-infected adolescents. These findings underscore the importance of Papanicolaou tests and promotion of safer sexual practices in this population.

Early Archiving and Predominance of Nonnucleoside Reverse Transcriptase Inhibitor–Resistant HIV‐1 among Recently Infected Infants Born in the United States

The extent to which drug-resistant human immunodeficiency virus type 1 (HIV-1) acquired through mother-to-child transmission (MTCT) or failed chemoprophylaxis populates viral reservoirs and limits responses to antiretroviral treatment in infants is unknown. We evaluated the presence, type, and persistence of drug-resistant HIV-1 in pretreatment plasma and resting CD4(+) T cells from US infants enrolled in a multicenter, open-label, phase 1/2 treatment trial of lopinavir/ritonavir (Pediatric AIDS Clinical Trials Group Protocol 1030) in young infants. Twenty-two consecutively enrolled infants initiating highly active antiretroviral therapy at a median age of 9.7 weeks and treated for up to 96 weeks were studied. Drug-resistant HIV-1 was present in 5 (23.8%) of 21 infants analyzed; 4 (80.0%) had nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant HIV-1, only 1 of whom had a history of receiving nevirapine chemoprophylaxis. All 4 infants had NNRTI-resistant variants other than the K103N mutation. The fifth infant had the M184V mutation. Drug-resistant virus was archived in the resting CD4(+) T cell latent reservoir in all 5 infants. The high rate, types, and early archiving of drug-resistant HIV-1 suggests that resistance testing be considered for infants, especially when an NNRTI-based regimen is planned. Furthermore, drug-resistance outcomes in infants should be an important secondary end point in MTCT trials.

Combining Cross‐Sectional and Prospective Data Methods to Improve Transition Parameter Estimation for Characterizing the Accumulation of HIV‐1 Drug Resistance Mutations

The order and rate of acquisition of HIV drug resistance mutations have been estimated from longitudinal and cross-sectional data using Markov models and branching trees, respectively. This article proposes methods that make use of both longitudinal and cross-sectional data simultaneously by employing link functions between the two parameter sets. Most functions that link the two parameter sets also depend on the time on treatment before the start of the study-information that may not be available. Nonetheless, under certain assumptions, some link functions eliminate the dependence on time. Using such functions, the two sources of information can be combined to improve the precision of parameter estimation. The method also accommodates error in the link functions from uncertainty in the assumptions required for the links or other reasons. These methods are applied to data from AIDS Clinical Trial Group protocol 398, a randomized comparison of mono- versus dual-protease inhibitor use in heavily treatment experienced HIV patients. Combining the two sources of information allows detection of differences between rates of transition that are not detectable using prospective data alone.