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1.
J Infect Dis ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38655842

RESUMEN

BACKGROUND: On-demand topical products could be an important tool for HIV prevention. We evaluated the safety, pharmacokinetics, and ex vivo pharmacodynamics of a tenofovir alafenamide/elvitegravir (TAF/EVG; 16 mg/20 mg) insert administered rectally. METHODS: MTN-039 was a Phase 1, open-label, single-arm, 2-dose study. Blood, rectal fluid (RF), and rectal tissue (RT) were collected over 72 hours (hr) following rectal administration of one and two TAF/EVG inserts for each participant. ClinicalTrials.gov Identifier: NCT04047420. RESULTS: TAF/EVG inserts were safe and well tolerated. EVG and tenofovir (TFV) were detected in blood plasma at low concentrations: median peak concentrations after 2 inserts were EVG 2.4 ng/mL and TFV 4.4 ng/mL. RT EVG peaked at 2-hr (median 2 inserts= 9 ng/mg) but declined to BLQ in the majority of samples at 24-hr, whereas TFV-DP remained high >2,000 fmol/million cells for 72-hr with 2 inserts. Compared to baseline, median cumulative log10 HIV p24 antigen of ex vivo rectal tissue HIV infection was reduced at each timepoint for both 1 and 2 inserts (p<0.065 and p<0.039, respectively). DISCUSSION: Rectal administration of TAF/EVG inserts achieved high rectal tissue concentrations of EVG and TFV-DP with low systemic drug exposure and demonstrable ex vivo inhibition of HIV infection for 72 hours.

2.
J Infect Dis ; 229(4): 1131-1140, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38019657

RESUMEN

BACKGROUND: Despite highly effective HIV preexposure prophylaxis (PrEP) options, no options provide on-demand, nonsystemic, behaviorally congruent PrEP that many desire. A tenofovir-medicated rectal douche before receptive anal intercourse may provide this option. METHODS: Three tenofovir rectal douches-220 mg iso-osmolar product A, 660 mg iso-osmolar product B, and 660 mg hypo-osmolar product C-were studied in 21 HIV-negative men who have sex with men. We sampled blood and colorectal tissue to assess safety, acceptability, pharmacokinetics, and pharmacodynamics. RESULTS: The douches had high acceptability without toxicity. Median plasma tenofovir peak concentrations for all products were several-fold below trough concentrations associated with oral tenofovir disoproxil fumarate (TDF). Median colon tissue mucosal mononuclear cell (MMC) tenofovir-diphosphate concentrations exceeded target concentrations from 1 hour through 3 to 7 days after dosing. For 6-7 days after a single product C dose, MMC tenofovir-diphosphate exceeded concentrations expected with steady-state oral TDF 300 mg on-demand 2-1-1 dosing. Compared to predrug baseline, HIV replication after ex vivo colon tissue HIV challenge demonstrated a concentration-response relationship with 1.9 log10 maximal effect. CONCLUSIONS: All 3 tenofovir douches achieved tissue tenofovir-diphosphate concentrations and colorectal antiviral effect exceeding oral TDF and with lower systemic tenofovir. Tenofovir douches may provide a single-dose, on-demand, behaviorally congruent PrEP option, and warrant continued development. Clinical Trials Registration . NCT02750540.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH , Neoplasias Colorrectales , Infecciones por VIH , Organofosfatos , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Masculino , Humanos , Tenofovir , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Emtricitabina , Homosexualidad Masculina , Difosfatos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico
3.
Sci Rep ; 13(1): 7547, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37161022

RESUMEN

To reduce HIV transmission, locally applied pre-exposure prophylaxis (PrEP) products for anorectal use will be important complements to oral and injectable PrEP products already available. It is critical to preserve an intact rectal epithelium and avoid an influx of mucosal HIV target cells with such product use. In this phase 1 clinical trial, we evaluated application of a topical rectal douche product containing Q-Griffithsin (Q-GRFT). Colorectal tissue samples were obtained via sigmoidoscopy at baseline, 1 and 24 h after single-dose exposure in 15 healthy volunteers. In situ staining for epithelial junction markers and CD4+ cells were assessed as an exploratory endpoint. A high-throughput, digitalized in situ imaging analysis workflow was developed to visualize and quantify these HIV susceptibility markers. We observed no significant differences in epithelial distribution of E-cadherin, desmocollin-2, occludin, claudin-1, or zonula occludens-1 when comparing the three timepoints or Q-GRFT versus placebo. There were also no differences in %CD4+ cells within the epithelium or lamina propria in any of these comparisons. In conclusion, the rectal epithelium and CD4+ cell distribution remained unchanged following topical application of Q-GRFT. In situ visualization of HIV susceptibility markers at mucosal sites could be useful to complement standard product safety assessments.


Asunto(s)
Infecciones por VIH , Membrana Mucosa , Humanos , Recto , Linfocitos T CD4-Positivos , Infecciones por VIH/prevención & control
4.
Antimicrob Agents Chemother ; 66(11): e0081622, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36255254

RESUMEN

Data to inform behaviorally congruent delivery of rectal microbicides as lubricants are scant. Dapivirine (DPV) is a nonnucleoside reverse transcriptase inhibitor which has been demonstrated to be well-tolerated and efficacious in multiple clinical trials when used in a vaginal ring formulation. DPV gel administered rectally with an applicator was found to be well-tolerated in a phase 1 clinical trial. MTN-033, a single site, open label, sequence randomized, crossover study, enrolled HIV-negative men to receive 0.05% DPV gel intrarectally using an applicator (2.5 g) and self-administered on an artificial phallus as lubricant (up to 10 g). The study evaluated the pharmacokinetics (in plasma, rectal fluid, and mucosal rectal tissue), safety, acceptability, and pharmacodynamics of DPV gel when applied rectally. Statistical comparisons between methods of application were performed using mixed effects models or Wilcoxon's signed rank tests. Sixteen participants used DPV gel by applicator and 15/16 participants used gel as lubricant (mean, 1.8 g; SD, 0.8). DPV plasma AUC0-24h after use as lubricant was estimated to be 0.41 times the AUC0-24h (95% CI 0.24, 0.88) after use with applicator. While DPV was quantifiable in plasma and luminal fluid, it was not quantifiable in tissue for both applicator and as lubricant administration. No related adverse events (AE) were reported, and 15/15 participants felt the gel was easy to use. Evidence of local delivery and systemic absorption of DPV when dosed as an anal lubricant supports the feasibility and potential for development of lubricant-delivered rectal microbicides. There were no safety concerns associated with use of DPV gel and participants reported finding it easy to use. However, lower DPV exposure in plasma and lack of quantifiable DPV in rectal tissue indicate that higher potency, concentration, and longer half-life antiretrovirals with optimized formulations will be needed to achieve protective tissue concentrations.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Masculino , Femenino , Lubricantes/uso terapéutico , Estudios Cruzados , Pirimidinas/farmacocinética , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Geles , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control
5.
AIDS Educ Prev ; 34(4): 257-271, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35994578

RESUMEN

Multipurpose prevention technologies (MPT) have been increasingly researched for their dual-purpose preventative properties against HIV and other STIs. The acceptability of PC-1005, a topical MPT candidate, was explored among men and women participating in the MTN-037 Phase I trial at two U.S. sites (Pittsburgh, PA, and Birmingham, AL). We triangulated quantitative and qualitative assessments of the acceptability of three volumes (4 mL, 16 mL, 32 mL) of PC-1005 administered rectally (N = 12; 6 males, 6 females). Participants rated overall gel acceptability on a scale of 1-10, with a median of 7.17 (SD = 2.04) and had positive feelings about all three dose volumes, citing them to be very comfortable or comfortable (dose 1 = 91.7%; dose 2 = 91.7%; dose 3 = 83.3%). High acceptability of and comfort with all three dose volumes shows promise for PC-1005 as an MPT to prevent HIV and STIs, warranting future clinical development.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Enfermedades de Transmisión Sexual , Adulto , Femenino , Infecciones por VIH/prevención & control , Humanos , Masculino , Enfermedades de Transmisión Sexual/prevención & control
6.
Br J Clin Pharmacol ; 88(4): 1667-1678, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34240467

RESUMEN

AIMS: Cabotegravir is an integrase strand transfer inhibitor in clinical development as long-acting (LA) injectable HIV preexposure prophylaxis. METHODS: This phase I study assessed pharmacokinetics of cabotegravir in plasma and anatomical sites associated with sexual HIV-1 transmission after repeated oral and single intramuscular (IM) LA dosing in healthy adults. Following a 28-day oral lead-in period of cabotegravir 30 mg and a washout period of 14-42 days, participants were administered a single ultrasound-guided gluteal IM cabotegravir LA 600-mg injection. The study objective was to characterize cabotegravir concentrations in plasma, cervical, vaginal and rectal tissues, and cervicovaginal and rectal fluids and up to Week 12 after IM injection. RESULTS: Nineteen participants enrolled and 16 completed the study through Week 52. Cabotegravir was detected in plasma and all tissues and fluids. Median plasma cabotegravir concentrations exceeded the in vitro protein-adjusted 90% maximal inhibitory concentration through Week 12. Median tissue- and fluid-to-plasma cabotegravir concentration ratios across all visits were 0.32 for rectal fluid and 0.08-0.16 for other tissues and fluids. Adjusted R2 coefficients between cabotegravir concentrations in plasma and cervical, vaginal and rectal tissues were 0.78, 0.79 and 0.90, respectively. Injection-site reactions were common (88% of participants) and were mostly grade 1 in intensity (82%). Two participants reported 11 non-drug-related serious adverse events. CONCLUSION: Concentrations of cabotegravir in tissues and fluids were proportional to plasma over time, with strong correlations between tissue and plasma concentrations. Cabotegravir LA tissue-to-plasma ratios may be important for understanding its use as preexposure prophylaxis.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Adulto , Dicetopiperazinas , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Inyecciones Intramusculares , Piridonas
7.
AIDS Res Hum Retroviruses ; 33(8): 820-826, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28296471

RESUMEN

During Phase 1 pharmacokinetic/pharmacodynamics studies, participants may undergo multiple sigmoidoscopies, with a collection of 10-20 biopsies during each procedure. This article characterizes the safety of flexible sigmoidoscopies in clinical trial participants. We determined the number of flexible sigmoidoscopies and rectal biopsies that participants underwent and analyzed the frequency, duration, and severity of flexible sigmoidoscopy-related adverse events (AEs). During the study period, 278 participants underwent 1,004 flexible sigmoidoscopies with the collection of 15,930 rectal biopsies. The average number of procedures per participant was 3.6 (median 3; range 1-25), with an average time interval between procedures of 61.8 days (median 28 days; range 1-1,159). There were no serious AEs. Sixteen AEs were related to flexible sigmoidoscopy and occurred in 16 participants, leading to an overall 1.6% (16/1,004) AE rate per procedure and 0.1% (16/15,930) AE rate per biopsy. Of the 16 AEs, 8 (50%) involved abdominal pain, diarrhea, bleeding, flatulence, and bloating, with an average duration of 4.7 days (median 1 day; range 1-28). Most (14/16) AEs were categorized as Grade 1 (mild), whereas two of the AEs were Grade 2 (moderate). No participant withdrew due to procedure-related AEs. Overall, the number of AEs caused by flexible sigmoidoscopy with multiple biopsies was low and the severity was mild, suggesting that this procedure can be safely integrated into protocols requiring repeated intestinal mucosal sampling.


Asunto(s)
Biopsia/efectos adversos , Ensayos Clínicos como Asunto , Sigmoidoscopía/efectos adversos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
8.
IEEE Trans Inf Technol Biomed ; 10(2): 377-84, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16617626

RESUMEN

Multicenter clinical trials are complex undertakings that require significant resources to ensure efficient, high quality research. This paper describes the goals, design, and implementation of a multicenter clinical trial database management system to support this aim. A large number of study sites or patients, and the goal of automatically generating large portions of data management infrastructure from common metadata, motivated the development of the system. This paper also describes extensions for a generalized project documentation system, and discusses plans for further extensions and improvements based on observed strengths, limitations, and anticipated technological change.


Asunto(s)
Sistemas de Administración de Bases de Datos , Documentación/métodos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Almacenamiento y Recuperación de la Información/métodos , Sistemas de Registros Médicos Computarizados , Estudios Multicéntricos como Asunto/métodos , Neumonía/clasificación , Neumonía/epidemiología , Triaje/estadística & datos numéricos , Infecciones Comunitarias Adquiridas/epidemiología , Neumonía/diagnóstico , Neumonía/terapia , Proyectos de Investigación
9.
Ann Emerg Med ; 43(6): 770-82, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15159711

RESUMEN

Community-acquired pneumonia causes more than 4 million episodes of illness each year and has high morbidity, mortality, and total cost of care. Nationwide, nearly 75% of community-acquired pneumonia patients are initially evaluated and treated in hospital-based emergency departments (EDs). Substantial variation exists in illness severity assessment, hospital admission decisions, and performance of recommended processes of care. We designed an ED-based quality improvement trial focused on the initial care of patients with community-acquired pneumonia. We used the Pneumonia Severity Index and level of arterial oxygenation to identify patients at low risk for 30-day mortality and to guide admission decisionmaking. We assessed the performance of recommended "best practices," consisting of assessment of arterial oxygenation, the collection of blood cultures for inpatients, and the timely initiation of appropriate empiric antibiotic therapy for inpatients and outpatients. We conducted a 32-site, cluster-randomized trial in Pennsylvania and Connecticut, comparing the effectiveness and safety of 3 guideline implementation strategies of increasing intensity. The multifaceted implementation plans were carried out in conjunction with each state's quality improvement organization. This article describes the background, objectives, and methodology of this trial to translate evidence-based knowledge on the quality and efficiency of care for community-acquired pneumonia into clinical practice.


Asunto(s)
Antibacterianos/uso terapéutico , Neumonía/terapia , Guías de Práctica Clínica como Asunto , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/terapia , Connecticut , Servicio de Urgencia en Hospital , Hospitalización , Humanos , Evaluación de Resultado en la Atención de Salud , Oxígeno/sangre , Pennsylvania , Neumonía/diagnóstico , Índice de Severidad de la Enfermedad , Gestión de la Calidad Total
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