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result(s) for
"Koss, Catherine A"
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HIV incidence after pre-exposure prophylaxis initiation among women and men at elevated HIV risk: A population-based study in rural Kenya and Uganda
by
Balzer, Laura B.
,
Brown, Lillian B.
,
Peng, James
in
Antiretroviral drugs
,
Antiretroviral therapy
,
Biology and Life Sciences
2021
Oral pre-exposure prophylaxis (PrEP) is highly effective for HIV prevention, but data are limited on HIV incidence among PrEP users in generalized epidemic settings, particularly outside of selected risk groups. We performed a population-based PrEP study in rural Kenya and Uganda and sought to evaluate both changes in HIV incidence and clinical and virologic outcomes following seroconversion on PrEP.
During population-level HIV testing of individuals ≥15 years in 16 communities in the Sustainable East Africa Research in Community Health (SEARCH) study (NCT01864603), we offered universal access to PrEP with enhanced counseling for persons at elevated HIV risk (based on serodifferent partnership, machine learning-based risk score, or self-identified HIV risk). We offered rapid or same-day PrEP initiation and flexible service delivery with follow-up visits at facilities or community-based sites at 4, 12, and every 12 weeks up to week 144. Among participants with incident HIV infection after PrEP initiation, we offered same-day antiretroviral therapy (ART) initiation and analyzed HIV RNA, tenofovir hair concentrations, drug resistance, and viral suppression (<1,000 c/ml based on available assays) after ART start. Using Poisson regression with cluster-robust standard errors, we compared HIV incidence among PrEP initiators to incidence among propensity score-matched recent historical controls (from the year before PrEP availability) in 8 of the 16 communities, adjusted for risk group. Among 74,541 individuals who tested negative for HIV, 15,632/74,541 (21%) were assessed to be at elevated HIV risk; 5,447/15,632 (35%) initiated PrEP (49% female; 29% 15-24 years; 19% in serodifferent partnerships), of whom 79% engaged in ≥1 follow-up visit and 61% self-reported PrEP adherence at ≥1 visit. Over 7,150 person-years of follow-up, HIV incidence was 0.35 per 100 person-years (95% confidence interval [CI] 0.22-0.49) among PrEP initiators. Among matched controls, HIV incidence was 0.92 per 100 person-years (95% CI 0.49-1.41), corresponding to 74% lower incidence among PrEP initiators compared to matched controls (adjusted incidence rate ratio [aIRR] 0.26, 95% CI 0.09-0.75; p = 0.013). Among women, HIV incidence was 76% lower among PrEP initiators versus matched controls (aIRR 0.24, 95% CI 0.07-0.79; p = 0.019); among men, HIV incidence was 40% lower, but not significantly so (aIRR 0.60, 95% CI 0.12-3.05; p = 0.54). Of 25 participants with incident HIV infection (68% women), 7/25 (28%) reported taking PrEP ≤30 days before HIV diagnosis, and 24/25 (96%) started ART. Of those with repeat HIV RNA after ART start, 18/19 (95%) had <1,000 c/ml. One participant with viral non-suppression was found to have transmitted viral resistance, as well as emtricitabine resistance possibly related to PrEP use. Limitations include the lack of contemporaneous controls to assess HIV incidence without PrEP and that plasma samples were not archived to assess for baseline acute infection.
Population-level offer of PrEP with rapid start and flexible service delivery was associated with 74% lower HIV incidence among PrEP initiators compared to matched recent controls prior to PrEP availability. HIV infections were significantly lower among women who started PrEP. Universal HIV testing with linkage to treatment and prevention, including PrEP, is a promising approach to accelerate reductions in new infections in generalized epidemic settings.
ClinicalTrials.gov NCT01864603.
Journal Article
A Prognostic Model of Persistent Bacteremia and Mortality in Complicated Staphylococcus aureus Bloodstream Infection
by
Carrasco-Triguero, Montserrat
,
Maskarinec, Stacey A.
,
Chambers, Henry F.
in
Adult
,
Aged
,
Aged, 80 and over
2019
Abstract
Background
Staphylococcus aureus is a leading cause of bacteremia, yet there remains a significant knowledge gap in the identification of relevant biomarkers that predict clinical outcomes. Heterogeneity in the host response to invasive S. aureus infection suggests that specific biomarker signatures could be utilized to differentiate patients prone to severe disease, thereby facilitating earlier implementation of more aggressive therapies.
Methods
To further elucidate the inflammatory correlates of poor clinical outcomes in patients with S. aureus bacteremia, we evaluated the association between a panel of blood proteins at initial presentation of bacteremia and disease severity outcomes using 2 cohorts of patients with S. aureus bacteremia (n = 32 and n = 124).
Results
We identified 13 candidate proteins that were correlated with mortality and persistent bacteremia. Prognostic modeling identified interleukin (IL)-8 and CCL2 as the strongest individual predictors of mortality, with the combination of these biomarkers classifying fatal outcome with 89% sensitivity and 77% specificity (P < .0001). Baseline IL-17A levels were elevated in patients with persistent bacteremia (P < .0001), endovascular (P = .026) and metastatic tissue infections (P = .012).
Conclusions
These results demonstrate the potential utility of selected biomarkers to distinguish patients with the highest risk for treatment failure and bacteremia-related complications, providing a valuable tool for clinicians in the management of S. aureus bacteremia. Additionally, these biomarkers could identify patients with the greatest potential to benefit from novel therapies in clinical trials.
Biomarkers identify S. aureus bacteremia patients at highest risk of treatment failure, with high circulating IL-17A levels at diagnosis prognostic for persistent bacteremia and chronic tissue infection foci while a combination of IL-8 and CCL2 identifies increased mortality risk.
Journal Article
Uptake of a patient‐centred dynamic choice model for HIV prevention in rural Kenya and Uganda: SEARCH SAPPHIRE study
by
Kakande, Elijah
,
Balzer, Laura B.
,
Petersen, Maya L.
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2023
Introduction
Person‐centred HIV prevention delivery models that offer structured choices in product, testing and visit location may increase coverage. However, data are lacking on the actual uptake of choices among persons at risk of HIV in southern Africa. In an ongoing randomized study (SEARCH; NCT04810650) in rural East Africa, we evaluated the uptake of choices made when offered in a person‐centred, dynamic choice model for HIV prevention.
Methods
Using the PRECEDE framework, we developed a persont‐centred, Dynamic Choice HIV Prevention (DCP) intervention for persons at risk of HIV in three settings in rural Kenya and Uganda: antenatal clinic (ANC), outpatient department (OPD) and in the community. Components include: provider training on product choice (predisposing); flexibility and responsiveness to client desires and choices (pre‐exposure prophylaxis [PrEP]/post‐exposure prophylaxis [PEP], clinic vs. off‐site visits and self‐ or clinician‐based HIV testing) (enabling); and client and staff feedback (reinforcing). All clients received a structured assessment of barriers with personalized plans to address them, mobile phone access to clinicians (24 hours/7 days/week) and integrated reproductive health services. In this interim analysis, we describe the uptake of choices of product, location and testing during the first 24 weeks of follow‐up (April 2021−March 2022).
Results
A total of 612 (203 ANC, 197 OPD and 212 community) participants were randomized to the person‐centred DCP intervention. We delivered the DCP intervention in all three settings with diverse populations: ANC: 39% pregnant; median age: 24 years; OPD: 39% male, median age 27 years; and community: 42% male, median age: 29 years. Baseline choice of PrEP was highest in ANC (98%) vs. OPD (84%) and community (40%); whereas the proportion of adults selecting PEP was higher in the community (46%) vs. OPD (8%) and ANC (1%). Personal preference for off‐site visits increased over time (65% at week 24 vs. 35% at baseline). Interest in alternative HIV testing modalities grew over time (38% baseline self‐testing vs. 58% at week 24).
Conclusions
A person‐centred model incorporating structured choice in biomedical prevention and care delivery options in settings with demographically diverse groups, in rural Kenya and Uganda, was responsive to varying personal preferences over time in HIV prevention programmes.
Journal Article
Quantifying Isoniazid Levels in Small Hair Samples: A Novel Method for Assessing Adherence during the Treatment of Latent and Active Tuberculosis
by
Chin, Aaron T.
,
Metcalfe, John
,
Bacchetti, Peter
in
Acquired immune deficiency syndrome
,
Adhesion
,
Adolescent
2016
Tuberculosis (TB) is the leading cause of death from an infectious pathogen worldwide and the most prevalent opportunistic infection in people living with HIV. Isoniazid preventive therapy (IPT) reduces the incidence of active TB and reduces morbidity and mortality in HIV-infected patients independently of antiretroviral therapy. However, treatment of latent or active TB is lengthy and inter-patient variability in pharmacokinetics and adherence common. Current methods of assessing adherence to TB treatment using drug levels in plasma or urine assess short-term exposure and pose logistical challenges. Drug concentrations in hair assess long-term exposure and have demonstrated pharmacodynamic relevance in HIV.
A large hair sample from a patient with active TB was obtained for assay development. Methods to pulverize hair and extract isoniazid were optimized and then the drug detected by liquid chromatography/ tandem mass spectrometry (LC/MS-MS). The method was validated for specificity, accuracy, precision, recovery, linearity and stability to establish the assay's suitability for therapeutic drug monitoring (TDM). Hair samples from patients on directly-observe isoniazid-based latent or active TB therapy from the San Francisco Department of Public Health TB clinic were then tested.
Our LC/MS-MS-based assay detected isoniazid in quantities as low as 0.02ng/mg using 10-25 strands hair. Concentrations in spiked samples demonstrated linearity from 0.05-50ng/mg. Assay precision and accuracy for spiked quality-control samples were high, with an overall recovery rate of 79.5%. In 18 patients with latent or active TB on treatment, isoniazid was detected across a wide linear dynamic range.
An LC-MS/MS-based assay to quantify isoniazid levels in hair with performance characteristics suitable for TDM was developed and validated. Hair concentrations of isoniazid assess long-term exposure and may be useful for monitoring adherence to latent or active TB treatment in the setting of HIV.
Journal Article
A Clinical Predictor Score for 30-Day Mortality among HIV-Infected Adults Hospitalized with Pneumonia in Uganda
by
Ayakaka, Irene
,
Koss, Catherine A.
,
den Boon, Saskia
in
Acquired immune deficiency syndrome
,
Adult
,
Adults
2015
Pneumonia is a major cause of mortality among HIV-infected patients. Pneumonia severity scores are promising tools to assist clinicians in predicting patients' 30-day mortality, but existing scores were developed in populations infected with neither HIV nor tuberculosis (TB) and include laboratory data that may not be available in resource-limited settings. The objective of this study was to develop a score to predict mortality in HIV-infected adults with pneumonia in TB-endemic, resource-limited settings.
We conducted a secondary analysis of data from a prospective study enrolling HIV-infected adults with cough ≥2 weeks and <6 months and clinically suspected pneumonia admitted to Mulago Hospital in Kampala, Uganda from September 2008 to March 2011. Patients provided two sputum specimens for mycobacteria, and those with Ziehl-Neelsen sputum smears that were negative for mycobacteria underwent bronchoscopy with inspection for Kaposi sarcoma and testing for mycobacteria and fungi, including Pneumocystis jirovecii. A multivariable best subsets regression model was developed, and one point was assigned to each variable in the model to develop a clinical predictor score for 30-day mortality.
Overall, 835 patients were studied (mean age 34 years, 53.4% female, 30-day mortality 18.2%). A four-point clinical predictor score was identified and included heart rate >120 beats/minute, respiratory rate >30 breaths/minute, oxygen saturation <90%, and CD4 cell count <50 cells/mm3. Patients' 30-day mortality, stratified by score, was: score 0 or 1, 12.6%, score 2 or 3, 23.4%, score 4, 53.9%. For each 1 point change in clinical predictor score, the odds of 30-day mortality increased by 65% (OR 1.65, 95% CI 1.39-1.96, p <0.001).
A simple, four-point scoring system can stratify patients by levels of risk for mortality. Rapid identification of higher risk patients combined with provision of timely and appropriate treatment may improve clinical outcomes. This predictor score should be validated in other resource-limited settings.
Journal Article
Long-Acting Injectable Cabotegravir for HIV Prevention: What Do We Know and Need to Know about the Risks and Consequences of Cabotegravir Resistance?
by
Mellors, John W.
,
Koss, Catherine A.
,
Parikh, Urvi M.
in
Antiretroviral therapy
,
Clinical trials
,
Cross-resistance
2022
Purpose of Review
Cabotegravir is a potent integrase strand transfer inhibitor (INSTI) recently approved as a long-acting injectable formulation for HIV prevention (CAB-LA). We summarize what is known about cabotegravir pharmacokinetics, activity, and emergence of resistance from in vitro, macaque and clinical studies, and we evaluate the risk of resistance from CAB-LA with on-time injections and after CAB-LA discontinuation.
Recent Findings
The accumulation of multiple INSTI mutations is required for high-level cabotegravir resistance, and the same mutation combinations may cause cross-resistance to dolutegravir, which is widely used for first-line antiretroviral therapy in low- and middle-income countries. Though CAB-LA was highly effective in preventing HIV, breakthrough infections did occur in trials of CAB-LA despite on-time injections, resulting in selection of single and combinations of INSTI resistance mutations.
Summary
As CAB-LA is scaled-up, prompt HIV diagnosis to prevent resistance, and resistance monitoring could help preserve the effectiveness of INSTIs for both HIV treatment and prevention.
Journal Article
Provider and Patient Perspectives of Rapid ART Initiation and Streamlined HIV Care: Qualitative Insights From Eastern African Communities
by
Petersen, Maya L.
,
Akatukwasa, Cecilia
,
Sang, Norton
in
African cultural groups
,
Anti-HIV Agents - therapeutic use
,
Antiretroviral drugs
2021
The Sustainable East Africa Research in Community Health (SEARCH), a universal test and treat (UTT) trial, implemented ‘Streamlined Care’—a multicomponent strategy including rapid linkage to care and antiretroviral therapy (ART) start, 3-monthly refills, viral load counseling, and accessible, patient-centered care provision. To understand patient and provider experiences of Streamlined Care to inform future care innovations, we conducted in-depth interviews with patients (n = 18) and providers (n = 28) at baseline (2014) and follow-up (2015) (n = 17 patients; n = 21 providers). Audio recordings were transcribed, translated, and deductively and inductively coded. Streamlined Care helped to decongest clinic spaces and de-stigmatize human immunodeficiency virus (HIV) care. Patients credited the individualized counselling, provider-assisted HIV status disclosure, and providers’ knowledge of patient's drug schedules, availability, and phone call reminders for their care engagement. However, for some, denial (repeated testing to disprove HIV+ results), feeling healthy, limited understanding of the benefits of early ART, and anticipated side-effects, and mistrust of researchers hindered rapid ART initiation. Patients’ short and long-term mobility proved challenging for both patients and providers. Providers viewed viral load counselling as a powerful tool to convince otherwise healthy and high-CD4 patients to initiate ART. Patient-centered HIV care models should build on the successes of Streamlined Care, while addressing persistent barriers.
#NCT01864683—https://clinicaltrials.gov/ct2/show/NCT01864603
Journal Article
Comparison of Measures of Adherence to Human Immunodeficiency Virus Preexposure Prophylaxis Among Adolescent and Young Men Who Have Sex With Men in the United States
by
Horng, Howard
,
Benet, Leslie Z
,
Saberi, Parya
in
Adolescent
,
and Commentaries
,
Anti-HIV Agents - administration & dosage
2018
Young men-who-have-sex-with-men (MSM) are disproportionately impacted by human immunodeficiency virus (HIV). Preexposure prophylaxis (PrEP) could reduce HIV acquisition among youth, but suboptimal adherence threatens effectiveness. Optimal metrics of PrEP adherence among adolescents have remain undefined.
The Adolescent Trials Network 110/113 studies provided daily oral PrEP with tenofovir (TFV) disoproxil fumarate/emtricitabine over 48 weeks to a diverse population of MSM (aged 15-22 years). Self-reported adherence was assessed and PrEP drug concentrations measured from hair and dried blood spot (DBS) samples; 23% of participants received Wisepill electronic monitoring devices. The average number of PrEP doses per week taken was estimated, and concordance between measures assessed.
Among 243 participants, hair samples were collected at 1186/1238 (96%) person-visits. The concordance of TFV levels in hair and TFV-diphosphate in DBS around thresholds consistent with taking ≥4 and 7 PrEP doses/week was high (76% and 80%). Hair and DBS concentrations correlated poorly with self-report and Wisepill metrics. Through week 12, 40%-60% of participants (by hair and DBS), ≤31% (Wisepill), and >85% (self-report) were estimated to have taken ≥4 PrEP doses/week (a threshold associated with protection among MSM). For all measures except self-report, adherence declined over time, with half of participants taking <2 doses/week by week 48.
Among youth on PrEP, adherence waned over time. Self-report overestimated adherence, and use of Wisepill was limited. Hair collection was highly acceptable and provided similar interpretations to DBS. Incorporation of either metric in future PrEP studies among youth could identify suboptimal adherence and trigger interventions.
Journal Article
Understanding Demand for PrEP and Early Experiences of PrEP Use Among Young Adults in Rural Kenya and Uganda: A Qualitative Study
by
Havlir, Diane V
,
Cohen, Craig R
,
Owino, Lawrence
in
Adults
,
Ambivalence
,
Antiretroviral agents
2020
Few studies have sought to understand factors influencing uptake and continuation of pre-exposure prophylaxis (PrEP) among young adults in sub-Saharan Africa in the context of population-based delivery of open-label PrEP. To address this gap, this qualitative study was implemented within the SEARCH study (NCT#01864603) in Kenya and Uganda, which achieved near-universal HIV testing, and offered PrEP in 16 intervention communities beginning in 2016–2017. Focus group discussions (8 groups, n = 88 participants) and in-depth interviews (n = 23) with young adults who initiated or declined PrEP were conducted in five communities, to explore PrEP-related beliefs and attitudes, HIV risk perceptions, motivations for uptake and continuation, and experiences. Grounded theoretical methods were used to analyze data. Young people felt personally vulnerable to HIV, but perceived the severity of HIV to be low, due to the success of antiretroviral therapy (ART): daily pill-taking was more threatening than the disease itself. Motivations for PrEP were highly gendered: young men viewed PrEP as a vehicle for safely pursuing multiple partners, while young women saw PrEP as a means to control risks in the context of engagement in transactional sex and limited agency to negotiate condom use and partner testing. Rumors, HIV/ART-related stigma, and desire for “proof” of efficacy militated against uptake, and many women required partners’ permission to take PrEP. Uptake was motivated by high perceived HIV risk, and beliefs that PrEP use supported life goals. PrEP was often discontinued due to dissolution of partnerships/changing risk, unsupportive partners/peers, or early side effects/pill burden. Despite high perceived risks and interest, PrEP was received with moral ambivalence because of its associations with HIV/ART and stigmatized behaviors. Delivery models that promote youth access, frame messaging on wellness and goals, and foster partner and peer support, may facilitate uptake among young people.
Journal Article
Case Series of People With HIV on the Long-Acting Combination of Lenacapavir and Cabotegravir: Call for a Trial
by
Hileman, Corrilynn O
,
Mayorga-Munoz, Francis
,
Short, William R
in
Editor's Choice
,
Global Health and Infectious Diseases
,
Mutation
2024
Abstract
Background
Injectable cabotegravir (CAB)/rilpivirine (RPV) is the only combination long-acting (LA) antiretroviral regimen approved for HIV. RPV may not be effective among individuals with non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance, which has >10% prevalence in many countries. Lenacapavir (LEN) is an LA capsid inhibitor given every 6 months, but has not been studied in combination with other LA agents.
Methods
We assembled a case series from 4 US academic medical centers where patients with adherence challenges were prescribed LEN subcutaneously every 26 weeks/CAB (+/− RPV) intramuscularly every 4 or 8 weeks. Descriptive statistics, including viral load (VL) outcomes, were summarized.
Results
All patients (n = 34: 76% male; 24% cis/trans female; 41% Black; 38% Latino/a; median age [range], 47 [28–75] years; 29% and 71% on CAB every 4 or 8 weeks) reported challenges adhering to oral ART. The reasons for using LEN/CAB with or without RPV were documented or suspected NNRTI mutations (n = 21, 59%), integrase mutations (n = 5, 15%), high VL (n = 6, 18%), or continued viremia on CAB/RPV alone (n = 4, 12%). Injection site reactions on LA LEN were reported in 44% (32% grade I, 12% grade 2). All patients but 2 (32/34; 94%) were suppressed (VL <75 copies/mL) after starting LEN at a median (range) of 8 (4–16) weeks, with 16/34 (47%) suppressed at baseline.
Conclusions
In this case series of 34 patients on LEN/CAB, high rates of virologic suppression (94%) were observed. Reasons for using LEN/CAB included adherence challenges and underlying resistance, mostly to NNRTIs. These data support a clinical trial of LEN/CAB among persons with NNRTI resistance.
Due to the prevalence of NNRTI-resistance worldwide, LA ART with CAB/RPV is not endorsed for low-and-middle-income-countries. This is the first case series examining LA-LEN/CAB to treat HIV in mostly NNRTI-resistant patients, serving as a call for a trial of this regimen.
Journal Article