Pharmacokinetics, Tolerability, and Safety of Doravirine and Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate Fixed-Dose Combination Tablets in Adolescents Living With HIV: Week 24 Results From IMPAACT 2014

BACKGROUND

We studied the pharmacokinetics (PK) and safety of 100-mg doravirine and doravirine/lamivudine/tenofovir disoproxil fumarate fixed-dose combination (100/300/300 mg DOR FDC) treatment in adolescents with HIV-1.

METHODS

Adolescents ages 12 to younger than 18 years were enrolled in 2 sequential cohorts. Cohort 1 evaluated intensive PK and short-term safety of 100-mg single-dose doravirine in adolescents ≥35 kg. Cohort 2 participants either initiated treatment with DOR FDC (antiretroviral (ARV)-naïve) or switched to DOR FDC from a previous ARV regimen (virologically suppressed). The first 10 Cohort 2 participants had intensive PK evaluations, and safety, sparse PK, and HIV RNA were assessed through week 24.

RESULTS

Fifty-five adolescents, median age 15.0 years and baseline weight 51.5 kg, were enrolled. Nine participants completed Cohort 1 PK assessments (8 of the 9 participants weighed ≥45 kg) and 45 initiated study drug in Cohort 2. The doravirine geometric mean (GM) AUC 0-∞ was 34.8 μM∙hour, and the GM C 24 was 514 nM after a single dose, with a predicted steady-state GM C 24,ss,pred of 690 nM. Cohort 2 enrolled adolescents weighing ≥45 kg. Plasma concentrations of doravirine, tenofovir, and lamivudine achieved by Cohort 2 participants were similar to those reported in adults. No drug-related serious or grade 3 or 4 adverse events occurred. Forty-two of 45 participants (93.3%; 95% CI: [81.7, 98.6]) achieved or maintained HIV-1 RNA <40 copies/mL.

CONCLUSIONS

Doravirine and DOR FDC achieved target PK in adolescents with HIV-1. DOR FDC was well-tolerated and maintained excellent virologic efficacy through 24 weeks, offering a favorable option for adolescents.

An exploratory qualitative study of pharmacy student perspectives of implicit bias in pharmacy practice

INTRODUCTION

Implicit biases can contribute to unfair treatment in healthcare and exacerbate healthcare disparities. Little is known about the implicit biases that exist within pharmacy practice and their behavioral manifestations. The purpose of this study was to explore pharmacy student perspectives about implicit bias in pharmacy practice.

METHODS

Sixty-two second-year pharmacy students attended a lecture on implicit bias in healthcare and engaged in an assignment designed to explore their thoughts about how implicit bias manifests or may manifest within pharmacy practice. Students' qualitative responses were content analyzed.

RESULTS

Students reported several examples in which implicit bias may emerge in pharmacy practice. Various forms of potential bias were identified including bias associated with patients' race, ethnicity, and culture, insurance/financial status, weight, age, religion, physical appearance and language, lesbian, gay, bisexual, transgender, queer/questioning and gender identity, and prescriptions filled. Students identified several potential implications of implicit bias in pharmacy practice including unwelcoming non-verbal behavior on the part of providers, differences in time devoted to interacting with patients, differences in empathy and respect, inadequate counseling, and (un)willingness to provide services. Students also identified factors that could precipitate biased behaviors such as fatigue, stress, burnout, and multiple demands.

CONCLUSIONS

Pharmacy students believed that implicit biases manifested in many different ways and were potentially associated with behaviors that resulted in unequal treatment in pharmacy practice. Future studies should explore the effectiveness of implicit bias trainings on reducing the behavioral implications of bias in pharmacy practice.

Ethically designing research to inform multidimensional, rapidly evolving policy decisions: Lessons learned from the PROMISE HIV Perinatal Prevention Trial

Research in rapidly evolving policy contexts can lead to the following ethical challenges for sponsors and researchers: the study's standard of care can become different than what patients outside the study receive, there may be political or other pressure to move ahead with unproven interventions, and new findings or revised policies may decrease the relevance of ongoing studies. These ethical challenges are considerable, but not unprecedented. In this article, we review the case of a multinational, randomized, controlled perinatal HIV prevention trial, the "PROMISE" (Promoting Maternal Infant Survival Everywhere) study. PROMISE compared the relative efficacy and safety of interventions to prevent mother to child transmission of HIV. The sponsor engaged an independent international ethics panel to address controversy about the study's standard of care and relevance as national and international guidelines changed. This ethics panel concluded that continuing the PROMISE trial as designed was ethically permissible because: (1) participants in all arms received interventions that were effective, and there was insufficient evidence about whether one intervention was more effective or safer than the other, and (2) data from PROMISE could be useful for a diverse range of stakeholders. In general, trials designed to inform rapidly evolving policy issues should develop mechanisms to revisit social value while recognizing that the value of research varies for diverse stakeholders with legitimate reasons to weigh evidence differently. We conclude by providing four reasons that trials may depart from the standard of care after a change in policy, while remaining ethically justifiable, and by suggesting how to improve existing trial oversight mechanisms to address evolving social value.

580. Association Between Central Venous Catheter Repair and Bloodstream Infections in a Pediatric Oncology Center

Background

Central venous catheters (CVCs) are important for healthcare delivery in pediatric oncology patients. It is common to repair CVC breakage to prevent replacement. Existing evidence regarding the association between CVC repair and bloodstream infections (BSI) is limited in the general pediatric population and lacking in pediatric oncology patients. We aim at evaluating whether repairing broken CVCs is associated with an increased risk for subsequent BSI in a pediatric oncology center.

Methods

This is a retrospective case-crossover study of pediatric oncology patients with broken CVCs that underwent repair between July 2015 and June 2017. The incidence and characteristics of BSI in the 30-day pre-repair period were compared with those in the 30-day post-repair period. Wilcoxon-Mann–Whitney and Fisher’s Exact tests were used for comparison of continuous and categorical variables, respectively. Univariate logistic regression was used to identify potential risk factors for BSI post CVC repair. Multiple breakages of the same CVC, and BSIs in overlapping observation periods of consecutive breakages are assumed independent.

Results

Sixty-four patients had 99 episodes of CVC breakage/repair in 68 CVCs. Median age (range) at repair was 2.5 (0.15–17.6) years. 48% of CVC breakages occurred in patients with solid tumors, 24% in HSCT recipients, and 19% in patients with leukemia. Only 25% of patients had neutropenia at repair and 14% had CVC occlusion 72 hours prior to breakage. All CVCs were made of silicone and 88% were double lumen external tunneled. First CVC breakage occurred at a median (range) of 130 (2–718) days since insertion, and CVCs were removed at a median (range) of 72.5 (3–753) days from the last repair. End of treatment was the most common cause (43%) for removal. The post-repair incidence of BSI was 4.5 per 1000 line-days compared with a pre-repair incidence of 4.3 (RR= 0.95, 95% CI 0.44, 2.18). There is no statistical difference between the characteristics of the pre-repair and post-repair BSI (Table 1). Figure 1 shows the organisms causing BSI before and after CVC repair. None of the evaluated variables was identified as a significant risk factor for BSI 30 days after CVC repair (Table 2).

Conclusion

Repair of CVC in pediatric oncology patients was not associated with increased risk of BSI.

Disclosures

All authors: No reported disclosures.

Triggered Escalating Real-Time Adherence Intervention to Promote Rapid HIV Viral Suppression Among Youth Living With HIV Failing Antiretroviral Therapy: Protocol for a Triggered Escalating Real-Time Adherence Intervention

Background

Youth living with HIV (YLWH) are confronted with many self-care challenges that can be experienced as overwhelming in the context of normal developmental processes that characterize adolescence and young adulthood. A sizable minority of YLWH have unsuppressed viral loads in the United States attributable to antiretroviral therapy (ART) nonadherence. Interventions to promote sustained viral suppression in YLWH are needed.

Objective

The aim of this study is to evaluate the efficacy of the Triggered Escalating Real-Time Adherence (TERA) intervention in comparison with standard of care (SOC) in YLWH (aged 13-24 years) failing ART on (1) primary outcome measures—HIV viral suppression (VLS), defined as both <200 copies/ml and <50 copies/ml at 12 weeks, and (2) secondary outcome measures—VLS rates and rates of ART adherence at 24, 36, and 48 weeks as well as patterns of adherence over time as measured by an electronic dose monitoring (EDM) device.

Methods

The TERA study is a phase 2, multisite clinical trial conducted with 120 YLWH failing ART (randomized 1:1 to TERA or SOC) at participating clinical sites within the Adolescent Medicine Trials Network for HIV/AIDS Interventions (ATN). Participants are followed for a total of 48 weeks. For TERA arm participants, the first 12 weeks involve delivery of the intervention. For all participants, clinical outcomes are collected throughout follow-up, and adherence is assessed using EDM over the full 48 weeks. During the 12-week intervention period, TERA arm participants receive 3 remote coaching sessions delivered in clinic via videoconferencing timed to coincide with baseline and follow-up clinical visits, text message reminders when the EDM has not been opened at dose time (which escalate to 2-way theory-informed short message service coaching interactions in response to real-time nonadherence), and review of dosing graphs produced by EDM at follow-up visits.

Results

Launch dates for enrollment varied by site. Enrollment began in April 2018 and is expected to be completed by August 2019, with results presented by the second quarter of 2021.

Conclusions

Effective, generalizable, and scalable approaches to rapidly assist YLWH failing to achieve and sustain VLS may have a substantial impact on individual health and efforts to curb transmission. Coaching for a brief but intensive period from remote coaches and using communication channels common to youth may offer multiple unique advantages in promoting self-care.

Trial Registration

ClinicalTrials.gov NCT03292432; https://clinicaltrials.gov/ct2/show/NCT03292432 (Archived by WebCite at http://www.webcitation.org/768J8ijjp).

International Registered Report Identifier (IRRID)

DERR1-10.2196/11416

What is new in perinatal HIV prevention?

PURPOSE OF REVIEW

The purpose of this review is to describe recent clinical trial, laboratory and observational findings that highlight both the progress that can be achieved in elimination of new pediatric infections in international clinical trial settings among HIV-infected breastfeeding women while also describing recent safety concerns related to currently used antiretroviral regimens. The article will also address the ongoing adherence challenges for HIV-infected mothers in taking their antiretroviral drugs. This information is timely and relevant as new regimens are being considered for both prevention of mother-to-child transmission (PMTCT) of HIV and HIV treatment options worldwide.

RECENT FINDINGS

The main themes described in this article include both efficacy of different antiretroviral therapy (ART) regimens currently being rolled out internationally for PMTCT as well as safety findings from recent research including a large multisite international trial, PROMISE.

SUMMARY

The findings from the IMPAACT PROMISE trial as well as other recent trial and observational findings suggest that while progress has been steady in reducing PMTCT worldwide, the goal of virtual elimination of pediatric HIV worldwide will require careful attention to optimizing safety of new regimens which are less dependent on maternal daily ART adherence and safer in preventing certain toxicities.

[Healthcare mistreatment attributed to discrimination among mapuche patients and discontinuation of diabetes care]

BACKGROUND

The negative impact of perceived discrimination on health outcomes is well established. However, less attention has been directed towards understanding the effect of perceived discrimination on health behaviors relevant for the treatment of diabetes in ethnic minorities.

AIM

To examine the effects of healthcare mistreatment attributed to discrimination on the continuity of Type 2 Diabetes (DM2) care among mapuche patients in a southern region of Chile.

MATERIAL AND METHODS

A non-probabilistic sample of 85 mapuche DM2 patients were recruited from public and private health systems. Eligibility criteria included having experienced at least one incident of interpersonal healthcare mistreatment. All participants answered an instrument designed to measure healthcare mistreatment and continuity of diabetes care.

RESULTS

Healthcare mistreatment attributed to ethnic discrimination was associated with the discontinuation of diabetes care.

CONCLUSIONS

Healthcare mistreatment attributed to discrimination negatively impacted the continuity of diabetes care, a fact which may provide a better understanding of health disparities in ethnic minorities.

Association between shunt-responsive idiopathic normal pressure hydrocephalus and alcohol

OBJECTIVE Idiopathic normal pressure hydrocephalus (iNPH) is characterized by ventriculomegaly, gait difficulty, incontinence, and dementia. The symptoms can be ameliorated by CSF drainage. The object of this study was to identify factors associated with shunt-responsive iNPH. METHODS The authors reviewed the medical records of 529 patients who underwent shunt placement for iNPH at their institution between July 2001 and March 2015. Variables associated with shunt-responsive iNPH were identified using bivariate and multivariate analyses. Detailed alcohol consumption information was obtained for 328 patients and was used to examine the relationship between alcohol and shunt-responsive iNPH. A computerized patient registry from 2 academic medical centers was queried to determine the prevalence of alcohol abuse among 1665 iNPH patients. RESULTS Bivariate analysis identified associations between shunt-responsive iNPH and gait difficulty (OR 4.59, 95% CI 2.32-9.09; p < 0.0001), dementia (OR 1.79, 95% CI 1.14-2.80; p = 0.01), incontinence (OR 1.77, 95% CI 1.13-2.76; p = 0.01), and alcohol use (OR 1.98, 95% CI 1.23-3.16; p = 0.03). Borderline significance was observed for hyperlipidemia (OR 1.56, 95% CI 0.99-2.45; p = 0.054), a family history of hyperlipidemia (OR 3.09, 95% CI 0.93-10.26, p = 0.054), and diabetes (OR 1.83, 95% CI 0.96-3.51; p = 0.064). Multivariate analysis identified associations with gait difficulty (OR 3.98, 95% CI 1.81-8.77; p = 0.0006) and alcohol (OR 1.94, 95% CI 1.10-3.39; p = 0.04). Increased alcohol intake correlated with greater improvement after CSF drainage. Alcohol abuse was 2.5 times more prevalent among iNPH patients than matched controls. CONCLUSIONS Alcohol consumption is associated with the development of shunt-responsive iNPH.

Quantitative evaluation of changes in gait after extended cerebrospinal fluid drainage for normal pressure hydrocephalus

Idiopathic normal pressure hydrocephalus (iNPH) is characterized by gait instability, urinary incontinence and cognitive dysfunction. These symptoms can be relieved by cerebrospinal fluid (CSF) drainage, but the time course and nature of the improvements are poorly characterized. Attempts to prospectively identify iNPH patients responsive to CSF drainage by evaluating presenting gait quality or via extended lumbar cerebrospinal fluid drainage (eLCD) trials are common, but the reliability of such approaches is unclear. Here we combine eLCD trials with computerized quantitative gait measurements to predict shunt responsiveness in patients undergoing evaluation for possible iNPH. In this prospective cohort study, 50 patients presenting with enlarged cerebral ventricles and gait, urinary, and/or cognitive difficulties were evaluated for iNPH using a computerized gait analysis system during a 3day trial of eLCD. Gait speed, stride length, cadence, and the Timed Up and Go test were quantified before and during eLCD. Qualitative assessments of incontinence and cognition were obtained throughout the eLCD trial. Patients who improved after eLCD underwent ventriculoperitoneal shunt placement, and symptoms were reassessed serially over the next 3 to 15months. There was no significant difference in presenting gait characteristics between patients who improved after drainage and those who did not. Gait improvement was not observed until 2 or more days of continuous drainage in most cases. Symptoms improved after eLCD in 60% of patients, and all patients who improved after eLCD also improved after shunt placement. The degree of improvement after eLCD correlated closely with that observed after shunt placement.

A randomized, placebo-controlled phase III trial of masitinib plus gemcitabine in the treatment of advanced pancreatic cancer

BACKGROUND

Masitinib is a selective oral tyrosine-kinase inhibitor. The efficacy and safety of masitinib combined with gemcitabine was compared against single-agent gemcitabine in patients with advanced pancreatic ductal adenocarcinoma (PDAC).

PATIENTS AND METHODS

Patients with inoperable, chemotherapy-naïve, PDAC were randomized (1 : 1) to receive gemcitabine (1000 mg/m(2)) in combination with either masitinib (9 mg/kg/day) or a placebo. The primary endpoint was overall survival (OS) in the modified intent-to-treat population. Secondary OS analyses aimed to characterize subgroups with poor survival while receiving single-agent gemcitabine with subsequent evaluation of masitinib therapeutic benefit. These prospectively declared subgroups were based on pharmacogenomic data or a baseline characteristic.

RESULTS

Three hundred and fifty-three patients were randomly assigned to receive either masitinib plus gemcitabine (N = 175) or placebo plus gemcitabine (N = 178). Median OS was similar between treatment-arms for the overall population, at respectively, 7.7 and 7.1 months, with a hazard ratio (HR) of 0.89 (95% CI [0.70; 1.13]. Secondary analyses identified two subgroups having a significantly poor survival rate when receiving single-agent gemcitabine; one defined by an overexpression of acyl-CoA oxidase-1 (ACOX1) in blood, and another via a baseline pain intensity threshold (VAS > 20 mm). These subgroups represent a critical unmet medical need as evidenced from median OS of 5.5 months in patients receiving single-agent gemcitabine, and comprise an estimated 63% of patients. A significant treatment effect was observed in these subgroups for masitinib with median OS of 11.7 months in the 'ACOX1' subgroup [HR = 0.23 (0.10; 0.51), P = 0.001], and 8.0 months in the 'pain' subgroup [HR = 0.62 (0.43; 0.89), P = 0.012]. Despite an increased toxicity of the combination as compared with single-agent gemcitabine, side-effects remained manageable.

CONCLUSIONS

The present data warrant initiation of a confirmatory study that may support the use of masitinib plus gemcitabine for treatment of PDAC patients with overexpression of ACOX1 or baseline pain (VAS > 20mm). Masitinib's effect in these subgroups is also supported by biological plausibility and evidence of internal clinical validation.

TRIAL REGISTRATION

ClinicalTrials.gov:NCT00789633.

Voriconazole plasma concentrations in immunocompromised pediatric patients vary by CYP2C19 diplotypes

AIM

Our objective was to describe the association between voriconazole concentrations and CYP2C19 diplotypes in pediatric cancer patients, including children homozygous for the CYP2C19*17 gain-of-function allele.

MATERIALS & METHODS

A linear mixed effect model compared voriconazole dose-corrected trough concentrations (n = 142) among CYP2C19 diplotypes in 33 patients (aged 1-19 years). Voriconazole pharmacokinetics was described by a two-compartment model with Michaelis-Menten elimination.

RESULTS

Age (p = 0.05) and CYP2C19 diplotype (p = 0.002) were associated with voriconazole concentrations. CYP2C19*17 homozygotes never attained therapeutic concentrations, and had lower dose-corrected voriconazole concentrations (median 0.01 μg/ml/mg/kg; p = 0.02) than CYP2C19*1 homozygotes (median 0.07 μg/ml/mg/kg). Modeling indicates that higher doses may produce therapeutic concentrations in younger children and in those with a CYP2C19*17/*17 diplotype.

CONCLUSION

Younger age and the presence of CYP2C19 gain-of-function alleles were associated with subtherapeutic voriconazole concentrations. Starting doses based on age and CYP2C19 status could increase the number of patients achieving therapeutic voriconazole exposure.

N0539 phase II trial of fulvestrant and bevacizumab in patients with metastatic breast cancer previously treated with an aromatase inhibitor: a North Central Cancer Treatment Group (now Alliance) trial

BACKGROUND

Based on preclinical studies, the vascular endothelial pathway is an important mechanism for estrogen receptor resistance. We conducted a phase II study of fulvestrant and bevacizumab in patients with aromatase inhibitor pretreated metastatic breast cancer.

PATIENTS AND METHODS

A single-stage phase II study was conducted with these objectives: 6-month progression-free survival (PFS), tumor response, toxic effect, and overall survival. Regimen: 250 mg fulvestrant days 1 and 15 (cycle 1) then day 1 (cycle 2 and beyond) and 10 mg/kg bevacizumab days 1 and 15 of each 4-week cycle.

RESULTS

At interim analysis, 20 eligible patients initiated treatment, 11 were progression free and on treatment at 3 months, not meeting the protocol-specified efficacy requirements (at least 12 of 20). Accrual remained open during interim analysis with 36 patients enrolling before final study closure. Among the 33 eligible patients, the median PFS was 6.2 months [95% confidence interval (CI) 3.6-10.1 months]. Of the 18 with measurable disease, 4 (22%) patients (95% CI 6% to 48%) had a confirmed tumor response (1 complete, 3 partial). The most common grade 3/4 adverse events were hypertension 3 (9%) and headache 3 (9%).

CONCLUSIONS

The fulvestrant/bevacizumab combination is safe and tolerable; however, it did not meet its statistical end point.

Detection of respiratory viruses in asymptomatic children undergoing allogeneic hematopoietic cell transplantation

Detection of respiratory viruses by molecular methods, in children without respiratory symptoms undergoing hematopoietic cell transplantation (HCT), has not been well described. A prospective study of 33 asymptomatic children detected respiratory viruses in 8 of 33 (24%) patients before HCT. Human rhinovirus (HRV) was detected in five patients, and human adenovirus (hADV) in three patients. Two additional patients shed HRV, and one shed human coronavirus (hCoV), post-HCT. Two patients had co-infections. Of the 11 asymptomatic patients where respiratory virus was detected, 3 (27%) later developed an upper respiratory tract infection, from the same virus.

Serum 25-hydroxyvitamin D response to vitamin D3 supplementation 50,000 IU monthly in youth with HIV-1 infection

CONTEXT

Vitamin D deficiency and insufficiency occur frequently in youth with HIV infection, particularly among those receiving the antiretroviral drug efavirenz. Optimal vitamin D dosing for treatment is unclear.

OBJECTIVE

Our objective was to evaluate safety and measure change in 25-hydroxyvitamin D (25-OHD) concentration from baseline to study wk 4 and 12 during treatment with vitamin D(3), 50,000 IU monthly.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a randomized double-blind, placebo-controlled multicenter trial of HIV-infected youth ages 18-24 yr, with viral load below 5000 copies/ml, on stable antiretroviral therapy.

INTERVENTION

INTERVENTION included vitamin D(3), 50,000 IU (n = 102), or matching placebo (n = 101) administered in three directly observed oral doses at monthly intervals.

RESULTS

At baseline, mean (sd) age was 20.9 (2.0) yr; 37% were female and 52% African-American, and 54% were vitamin D deficient/insufficient (25-OHD < 20 ng/ml), with no randomized group differences. Of evaluable participants vitamin D deficient/insufficient at baseline who were administered vitamin D, 43 of 46 (93%) had sufficient 25-OHD by wk 12. Vitamin D supplementation increased 25-OHD serum concentration from a baseline of 21.9 (13.3) to 35.9 (19.1) ng/ml at wk 12 (P < 0.001) with no change for placebo. Although use of the antiretroviral efavirenz was associated with lower baseline 25-OHD concentration, efavirenz did not diminish the response to vitamin D supplementation. There was no treatment-related toxicity.

CONCLUSIONS

Supplementation with vitamin D(3) 50,000 IU monthly for three doses was safe. Increases in 25-OHD occurred in treated participants regardless of antiretroviral regimen.

Recovery of Salmonella and Escherichia coli from commercial egg shells and effect of translucency on bacterial penetration in eggs

This experiment was conducted to study the prevalence of Salmonella and Escherichia coli (E. coli). from the surface of egg shells, egg shell membranes or pores, and internal contents from unwashed eggs collected from commercial caged layer farms in Australia. Egg shell swabs, shell crush and egg internal contents (yolk and albumen) of an individual egg were processed for bacteriological examination. Salmonella spp. were not detected from any of the egg shell surfaces, egg shell crush or egg internal contents. Thirty five E. coli isolates were isolated from the egg shell surface. Ten E. coli strains were also isolated from shell crush. However, the internal contents of eggs appeared to be sterile. Polymerase chain reaction was performed on forty-five E. coli isolates using primers for heat stable enterotoxin genes A and B (STa and STb) and also for colicin V gene (cvaC). STa gene was detected in four E. coli isolates isolated from egg shell surfaces. All the E. coli isolates were negative for STb and cvaC genes. These data provide useful information regarding the prevalence of virulent E. coli and Salmonella spp. on and in unwashed eggs collected from layer farms. These data also suggest that unwashed eggs collected from caged layer farms are unlikely to be sources of Salmonella outbreaks. Egg shell translucency could be due to changes in the mammillary layer and mamillary cores during the early phases of egg shell formation and has the potential to increase the incidence of microcracks in egg shells, and hence, may be responsible for bacterial penetration. There was a significant correlation between egg shell translucency and egg shell penetration by Salmonella Infantis and E coli. Both strains of bacteria were able to penetrate the translucent egg shells even at very low doses. The penetration, however, was hindered in both translucent and non translucent eggs at 4 degrees C, as compared with room temperature which highlights the importance of storage of eggs at refrigerated temperatures.

Effectiveness of varicella vaccine in children infected with HIV

Although varicella vaccine is given to clinically stable human immunodeficiency virus (HIV)-infected children, its effectiveness is unknown. We assessed its effectiveness by reviewing the medical records of closely monitored HIV-infected children, including those receiving highly active antiretroviral therapy (HAART) between 1989 and 2007. Varicella immunization and development of varicella or herpes zoster were noted. Effectiveness was calculated by subtracting from 1 the rate ratios for the incidence rates of varicella or herpes zoster in vaccinated versus unvaccinated children. The effectiveness of the vaccine was 82% (95% confidence interval [CI], 24%-99%; P = .01) against varicella and was 100% (95% CI, 67%-100%; P < .001) against herpes zoster. When the analysis was controlled for receipt of HAART, vaccination remained highly protective against herpes zoster.

Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of `original antigenic sin' is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus) and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans.

N0539 Phase II Trial of Fulvstrant and Bevacizumab in Patients with Metastatic Breast Cancer Previously Treated with an Aromatase Inhibitor: A North Central Cancer Treatment Group Trial

Background: Treatment of aromatase refractory metastatic breast cancer (MBC) is difficult and challenging. Estrogen receptor (ER) resistance causes enhanced expression of the vascular endothelial growth factor (VEGF).Several studies have shown that the ER interacts with the VEGF pathway and is an important mechanism of resistance. Therefore we embarked on a phase II study of fulvestrant, a complete ER suppressor and bevacizumab, a well studied VEGF monoclonal antibody in aromatase refractory MBC patients. Methods: A single stage phase II study with an interim analysis of fulvestrant and bevacizumab was conducted with these objectives: 6 month progression-free survival rate (PFS), tumor response, toxicity, and overall survival. Regimen: fulvestrant 250 mg day1 and 15 (cycle 1) then day 1 (cycle 2 and beyond) and bevacizumab 10mg/kg days 1 and 15 of each 4 weeks is a cycle. Results: At the time of interim analysis, 11/20 evaluable patients achieved 3-month progression-free survival status while remaining on treatment for at least 3 months, not meeting the protocol specified efficacy requirements and thus halting accrual. 36 patients were enrolled from September 2007-December 2008; 33 patients were evaluable. Number of prior metastatic chemotherapy regimens: 0 in 26 patients and 1 in 7 patients. 22 (67%) patients received prior hormonal therapy in the metastatic setting. 18 (55%) had measurable disease. A median of 6 cycles (range 1-19) were administered. 12/33 evaluable patients (95% CI:20-55%) achieved 6-month progression-free survival status while remaining on treatment for a least 6 months. Among 18 patients with measurable disease, 2 (11%) patients CI:1.4-35%) had a confirmed tumor reponse (both PR). Additionally, 2 patients had stable disease for greater than 6 months, for a clinical benefit rate of 22%. Median follow up was 8.5 months (range 1.7-17.5 months). Median progression-free survival was 6.2 months (95% CI:5.4-10.1 months). The 6 -month overall survival rate was 84.8% (95% CI 73.5-98%). The median dose level administered was 250 mg for fulvestrant and 10 mg/kg for bevacizumab for cycles 1-19. The most common grade 3/4 adverse events (AEs) were hypertension 2 (6%), headache pain 2 (6%), and confusion 2 (6%). There was 1 grade 5 central nervous system hemorrhage. 13 (39%) patients experienced a grade 3 non-hematologic AE and 4 (12%) experience a grade 4+ non-hematologic AE. Conclusion: Fulvestrant/bevacizumab is safe and tolerable. Although this regimen did not meet its statistical endpoint, 22% of evaluable patients with aromatase refractory diesease achieved clinical benefit with minimal toxicity.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4096.

Clinical practice guidelines for the diagnosis and management of intravascular catheter-related infection: 2009 Update by the Infectious Diseases Society of America

These updated guidelines replace the previous management guidelines published in 2001. The guidelines are intended for use by health care providers who care for patients who either have these infections or may be at risk for them.

Meningioma presenting with transient ischaemic attacks

A case of sphenoid wing meningioma mimicking the presentation of a transient ischaemic attack (TIA) is described. Based on findings from neuroimaging in this case, possible explanations of the mechanism of this uncommon presentation of meningiomas are discussed and the literature is reviewed.

Posterior fossa arachnoid cyst presenting with unilateral tremor

A rare case of unilateral benign essential tremor is presented that responded to surgical excision of a posterior fossa arachnoid cyst.

N0337: Phase II study of capecitabine in combination with vinorelbine and trastuzumab for the first or second treatment of HER2+ metastatic breast cancer

1020

Background: Trastuzumab-containing regimes have dramatically improved outcome of patients with HER2+ breast cancer. Efforts to improve efficacy and tolerability of combination regimens with this monoclonal antibody are important for patient care. Thus, we conducted a multi-institutional phase II study of a triplet combination in patients eligible to receive either first- or second-line treatment for HER2+ metastatic breast cancer (MBC). Methods: A phase II study designed to test that the true confirmed response rate (CRR) was at most 45% versus a true CRR of at least 65% was done (March 2005-June 2008). This design required that at least 25/45 confirmed responses in evaluable patients for the treatment to be considered promising. Patients received capecitabine 825 mg/m2 po (days 1–14), vinorelbine intravenously (IV) 25 mg/m2 days 1 and 8 every 3 weeks and trastuzumab IV 8mg/kg day 1, week 1, and then 6 mg/kg q 3 weeks. Tissue and blood have been collected for future studies on biomarkers. Results: 47 women were accrued, one patient cancelled participation prior to receiving any study drug, and another had a major protocol violation. 45 patients were evaluable and 30 (67%) achieved a confirmed response, (26 patients, 58% had a confirmed partial response and 4 patients, 9% had a confrimed complete response). Median progression free survival was 11.3 months (95% CI 8.4–23.2 months), median overall survival was 27.2 months (95% CI: 26.6-NA months), and among the 30 responders, the median duration of response time was 15.5 months (95% 7.7–26.1 months). The most common grade 3 events include neutropenia 61%, fatigue 13%, skin reaction-hand-foot 11%, and leukopenia 11%. Alopecia was not noted with this regimen. Conclusions: This triplet combination is effective, safe, and is promising in patients with HER2+ MBC. A phase III study should be conducted to compare the best doublet with this triplet combination whether this would lead to better clinical outcomes.

[Table: see text]

Preclinical and clinical development of a multi-envelope, DNA-virus-protein (D-V-P) HIV-1 vaccine

The human immune system has evolved to recognize antigenic diversity, a strength that has been harnessed by vaccine developers to combat numerous pathogens (e.g., pneumococcus, influenza virus, rotavirus). In each case, vaccine cocktails were formulated to include antigenic variants of the target. To combat HIV-1 diversity, we assembled a cocktail vaccine comprising dozens of envelopes, delivered as recombinant DNA, vaccinia virus, and protein for testing in a clinical trial. One vaccinee has now completed vaccinations with no serious adverse events. Preliminary analyses demonstrate early proof-of-principle that a multi-envelope vaccine can elicit neutralizing antibody responses toward heterologous HIV-1 in humans.

Prophylactic antibiotics reduce morbidity due to septicemia during intensive treatment for pediatric acute myeloid leukemia

BACKGROUND

The aim of this study was to determine whether antibiotic prophylaxis during periods of neutropenia reduced streptococcal (S. viridans) sepsis and overall bacterial sepsis.

METHODS

The authors reviewed outcomes of 78 evaluable patients who were consecutively treated for acute myeloid leukemia (AML) from October 2002 through January 2007. Several successive prophylactic antibiotic regimens were used. All patients received antifungal prophylaxis with oral voriconazole.

RESULTS

Oral cephalosporins did not significantly reduce the odds of bacterial sepsis (P = .81) or streptococcal (S. viridans) sepsis (P = .90) relative to no prophylaxis. Intravenous (iv) cefepime completely prevented streptococcal (S. viridans) sepsis and reduced the odds of bacterial sepsis 91% (P < .0001) relative to no prophylaxis, but resistant gram-negative bacteria emerged in 2 patients. Vancomycin with oral ciprofloxacin or a cephalosporin reduced the odds of bacterial sepsis by 93% (P < .0001) and streptococcal (S. viridans) sepsis by 99% (P < .0001). The fungal infection rate did not differ significantly between patients who did and did not receive antibiotic prophylaxis (1.0 per 1000 patient-days for both groups). The observed reduction in average hospital days per chemotherapy course for patients given vancomycin regimens or cefepime was 5.7 (P < .0001) and 4.1 (P = .0039) days, respectively. No reduction was observed with oral cephalosporins (P = .10). Furthermore, vancomycin regimens or cefepime were associated with a 20% reduction in healthcare charges (P = .0015) relative to using no antibiotics. One patient, who was on oral cefuroxime alone, died of septicemia.

CONCLUSIONS

Prophylaxis with intravenous cefepime or a vancomycin regimen, and voriconazole, reduced morbidity in children with AML, and resulted in dramatic decreases in the incidence of septicemia and hospitalization days.

A randomised comparison of the single use LMA Flexible with the reusable LMA Flexible in paediatric dental day-case patients

In this study we compared the performance of the single use flexible laryngeal mask airway (LMA Flexible) with the original reusable LMA Flexible in paediatric dento-alveolar day-case surgery. The aim of the study was to determine whether these two supraglottic airway devices were clinically equivalent when used for simple dental extractions in children under general anaesthesia. This randomised comparative trial in 100 healthy children used first attempt airway insertion success as its primary outcome measure. Secondary outcomes included the adequacy of ventilation, incidence of airway obstruction and the requirement for device manipulation and the incidence of adverse airway outcomes during recovery from anaesthesia. No difference was found between the devices in first attempt insertion success rate (94% with reusable LMA Flexible and 90% with single use LMA Flexible, p = 0.358), and ease of insertion was also similar (p = 0.5). Both devices performed equally well during surgery, with no significant differences in episodes of intra-operative airway compromise (p = 0.387), and both the single use and reusable LMA Flexible displayed excellent recovery characteristics, with no occurrences of emergence airway obstruction. No blood was discovered within the inner LMA tube shaft in either device, implying that both protected against tracheobronchial soiling. We conclude therefore that the single use LMA Flexible is an acceptable alternative to the reusable LMA Flexible.

An introduction to Toll-like receptors and their possible role in the initiation of labour

Toll-like receptors (TLR) have emerged as key upstream mediators of inflammation at many tissue sites in humans. Inflammatory processes are involved in the process of parturition suggesting that TLR activity within gestation-associated tissues might have an important role in the initiation and/or maintenance of normal term labour and in various pathological states of pregnancy such as infection-associated preterm labour. Either TLRs or their signalling molecules might be excellent therapeutic targets for prevention of preterm labour.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Population pharmacokinetics of micafungin in pediatric patients and implications for antifungal dosing

The echinocandins potentially have an important role in treatment of infections caused by Candida spp. and Aspergillus spp. in immunocompromised children. However, there are no population pharmacokinetic models of the echinocandins for pediatric patients. The safety and descriptive pharmacokinetics of micafungin in children were recently reported. However, a population pharmacokinetic model in children is needed in order to accurately determine the dosage of micafungin that produces an equivalent magnitude of drug exposure to that observed in adults. In order to explore the effect of weight on micafungin pharmacokinetics, a standard two-compartment pharmacokinetic model, a linear model, and an allometric power model were developed. For all three models, the fit to the data was excellent, with comparable measures of precision and bias. However, the superior log-likelihood value of the allometric power model suggested that it best reflected the data and was therefore chosen for a more detailed analysis of the magnitude and pattern of drug exposure which develop following the administration of micafungin. The allometric power model suggested that clearance in smaller children is higher than that predicted on the basis of weight alone. Consequently, a degree of dosage increase is required in smaller children to ensure comparable levels of drug exposure to those observed in larger children and adults. The allometric power model developed in this study enables identification of pediatric dosage regimens of micafungin which, based upon Monte Carlo simulations, result in equivalent drug exposures to those observed in adults, for which antifungal efficacy has been established.

Translational correlates, including outcome for patients with ER-/PR-/HER2- (triple negative (TNeg)) disease from N0234, a phase II trial of gemcitabine and erlotinib for pts with previously treated metastatic breast cancer (MBC)

1071

Background: N0234 is a phase II trial of gemcitabine at 1000 mg/m2 days 1 and 8 of a 21 day cycle and erlotinib at 150 mg daily in patients with previous therapy with either an anthracycline or a taxane for MBC. A partial response (PR) rate of 17% has been reported (ASCO 2005). Recent information suggests that over-expression of the EGFR pathway is frequent in patients with TNeg MBC. Methods: Tissue and serum were obtained for translational studies of ER, PR, HER2, and proteins related to EGFR pathway on tissue using immunohistochemistry; CK19, mammoglobin, and TTK on circulating tumor cells (CTCs). Markers were evaluated centrally, blinded to patient outcome. Complete data were available in 57 of 59 eligible patients; 20/57 patients (pts) were TNeg. Results: A PR rate of 25% and clinical benefit rate (PR + stable disease > 6 months)of 25% was observed in TNeg pts as compared to a PR rate of 14% (p = 0.30) and clinical benefit rate 22% (p= 0.75) for non-TNeg pts. Median progression free survival 72 days vs 98 days (p=0.13) and overall survival 227 days vs 738 days (p<0.001) were shorter for TNeg pts. Translational results for the EGFR pathway proteins and CTC analysis is forthcoming. Conclusions: The combination of gemcitabine and erlotinib appears to be as active in the non-TNeg and TNeg subset of patients on this trial. TNeg patients had an inferior clinical result, confirming the poor outcome seen in these patients. Data for the remaining biomarkers potentially predictive of activity will be presented. Supported by CA-25224, CA-37404.

[Table: see text]

Patient dose from 3D rotational neurovascular studies

The use of image-guided interventional radiological techniques is increasing in prevalence and complexity. Imaging system developments have helped improve the information available to interventionalists to plan and guide procedures. Information on doses to patients resulting from alternative imaging techniques or protocols is useful for both the process of justifying particular procedures and in optimizing the resultant exposures. Such information is not always available, especially for new or developing imaging techniques. We have undertaken a study of doses to patients associated with two alternative imaging methods for pre-intervention assessment of intracranial aneurysms. In the first technique the aneurysm is assessed from a series of digital subtraction angiography (DSA) runs taken at different imaging projections. The second technique involved acquiring images from one single image run while the imaging system rotated 180 degrees around the patient's head. In this technique, the aneurysm was then evaluated from a 3D reconstruction of the projection images. Effective doses were calculated using a computer model to simulate the exposure geometry and parameters. The mean dose from the DSA protocol used at our centre was 3.4 mSv and from the 3D rotational angiography (RA) technique was 0.20 mSv.

Safety of bevacizumab plus chemotherapy as first-line treatment of patients with metastatic colorectal cancer: Updated results from a large observational registry in the US (BRiTE)

3536

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy for patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line chemotherapy. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: To facilitate and evaluate enrollment of a typical community-based mCRC population, eligibility criteria were minimized. Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Patients are followed for up to 3 years, and safety data including targeted BV-associated serious adverse events (SAEs) are updated every 3 months (mo). Results are based on descriptive analyses and are not adjusted for propensity of treatment, baseline characteristics, and treatment effects. Results: 1968 patients were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo by Nov 4, 2005. SAEs were reported in 12.0% of patients including gastrointestinal perforation (GIP) (1.7%), postoperative bleeding/wound healing complications (1.2%), arterial thromboembolic events (ATE) (2.1%), and grade 3–4 bleeding (1.9%). 3.2% of patients discontinued BV due to a BV-related toxicity, most commonly bleeding. For patients with the respective event(s), median time to first event was 2.1 mo for GIP, 3.5 mo for ATE and 4.0 mo for grade 3–4 bleeding. 8.9% of patients with no history of hypertension (HTN) developed HTN requiring medication and 6.2% of patients who had HTN requiring medication at baseline experienced worsening of their HTN while on study treatment. Conclusions: In this unselected population of patients with mCRC, the safety profile of BV plus various chemotherapy regimens appears consistent with that observed in the pivotal BV trial. Overall discontinuation of BV due to a BV-related toxicity was uncommon. In this large community-based observational registry, no new BV associated safety issues have been identified.

[Table: see text]

Risk factors for gastrointestinal perforations in patients with metastatic colorectal cancer receiving bevacizumab plus chemotherapy

3535

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy in patients (pts) with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of pts with mCRC receiving BV plus first-line chemotherapy (CT). Incidence rate, temporal pattern, and potential risk factors associated with gastrointestinal perforation (GIP) were explored. Methods: Baseline patient characteristics (BC), including prospectively identified potential risk factors for GIP, were collected at study entry. Safety data were collected every 3 months (mo). Logistic regression models, adjusted and unadjusted for treatment assignment, were used to identify BC potentially associated with GIP. Results: 1968 pts were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo as of Nov 4, 2005. GIPs were observed in 34 pts (1.7%). For pts with GIP, median time to first event was 2.1 mo; the majority of events were non-fatal and occurred within the first 3 mo after starting BV. BC including GI medical history (chronic aspirin or NSAID use, peptic ulcer disease, diverticulosis) were similar in pts with or without GIP and with earlier or later GIP onset (≤ or >3 mo from start of BV). Although adjusted models did not show any significant BC, GIP rates were numerically higher in pts with primary tumor intact (2.6%) vs. resected (1.6%). Furthermore, univariate analyses revealed a significant difference between intact (2.3%) and resected (0.8%) primary tumor for earlier GIP (≤3 mo from start of BV). The majority of pts with GIP had at least one of the following: acute diverticulitis, intra-abdominal abscess, gastrointestinal obstruction, tumor at GIP site, abdominal carcinomatosis, prior abdominal or pelvic radiation therapy. Conclusions: Preliminary analyses indicate the incidence of GIP in this large, community-based observational registry is similar to that previously reported in phase III mCRC trials with BV. No associations between specific BCs and an increased risk of GIP were identified. Patients with primary tumor intact were more likely to incur a GIP within the first 3 mo of starting BV and CT.

[Table: see text]