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1.
Regul Toxicol Pharmacol ; 142: 105430, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37308050

RESUMO

This paper proposes a scientifically justified and harmonized strategy to control cleaning agent ingredients' (CAIs) residues in pharmaceutical manufacturing. Firstly, we demonstrate that worst-case cleaning validation calculations on CAI residues with representative GMP standard cleaning limits (SCLs) are enough to control CAI residues of low concern to safe levels. Secondly, a new harmonized strategy for the toxicological assessment of CAI residues is presented and validated. The results establish a framework applicable to cleaning agent mixtures based on hazard and exposure considerations. This framework is primarily based on the hierarchy of a single CAI's critical effect, where the lowest resulting limit may become the driver of the cleaning validation process. The six critical effect groups are: (1) CAIs of low concern based on safe exposure reasoning; (2) CAIs of low concern based on the mode of action reasoning; (3) CAIs with local concentration-dependent critical effects; (4) CAIs with dose-dependent systemic critical effects for which a route-specific PDE should be calculated; (5) poorly characterized CAIs with unknown critical effect for which a default value of 100 µg/day is proposed; (6) poorly characterized CAIs which should be avoided because of potential mutagenicity and/or potency.


Assuntos
Contaminação de Medicamentos , Indústria Farmacêutica , Contaminação de Medicamentos/prevenção & controle , Medição de Risco , Preparações Farmacêuticas
2.
Antimicrob Agents Chemother ; 67(3): e0142622, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36744891

RESUMO

Moxifloxacin is included in some treatment regimens for drug-sensitive tuberculosis (TB) and multidrug-resistant TB (MDR-TB). Aiming to optimize dosing, we described moxifloxacin pharmacokinetic and MIC distribution in participants with MDR-TB. Participants enrolled at two TB hospitals in South Africa underwent intensive pharmacokinetic sampling approximately 1 to 6 weeks after treatment initiation. Plasma drug concentrations and clinical data were analyzed using nonlinear mixed-effects modeling with simulations to evaluate doses for different scenarios. We enrolled 131 participants (54 females), with median age of 35.7 (interquartile range, 28.5 to 43.5) years, median weight of 47 (42.0 to 54.0) kg, and median fat-free mass of 40.1 (32.3 to 44.7) kg; 79 were HIV positive, 29 of whom were on efavirenz-based antiretroviral therapy. Moxifloxacin pharmacokinetics were described with a 2-compartment model, transit absorption, and elimination via a liver compartment. We included allometry based on fat-free mass to estimate disposition parameters. We estimated an oral clearance for a typical patient to be 17.6 L/h. Participants treated with efavirenz had increased clearance, resulting in a 44% reduction in moxifloxacin exposure. Simulations predicted that, even at a median MIC of 0.25 (0.06 to 16) mg/L, the standard daily dose of 400 mg has a low probability of attaining the ratio of the area under the unbound concentration-time curve from 0 to 24 h to the MIC (fAUC0-24)/MIC target of >53, particularly in heavier participants. The high-dose WHO regimen (600 to 800 mg) yielded higher, more balanced exposures across the weight ranges, with better target attainment. When coadministered with efavirenz, moxifloxacin doses of up to 1,000 mg are needed to match these exposures. The safety of higher moxifloxacin doses in clinical settings should be confirmed.


Assuntos
Antituberculosos , Tuberculose Resistente a Múltiplos Medicamentos , Feminino , Humanos , Adulto , Moxifloxacina/uso terapêutico , Antituberculosos/farmacocinética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Alcinos/uso terapêutico
3.
S Afr Med J ; 112(12): 901-903, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36472319

RESUMO

Treatment and management of plant toxicosis is made more difficult when an alien plant species is ingested, as identification of the toxin may pose a challenge. High-resolution mass spectrometers are required for the toxicological analysis of samples in these cases owing to their ability to scan large mass ranges and accurately identify mass features. We present this case to highlight the value of this technology in clinical toxicology. A middle-aged woman reported visual impairment, dizziness and numbness of her mouth and tongue following the ingestion of a berry. Over time her condition deteriorated, warranting toxicological analysis. The tree the berry came from was identified as Cornynocarpus laevigatus, which is known to produce the karakin neurotoxin. The patient's samples and the husk and pulp of the berries were analysed using a high-resolution mass spectrometer. This resulted in the identification of the toxin in the berry kernel and husk and patient's hair, suggesting that karakin could have contributed to the patient's condition.


Assuntos
Glucose , Pessoa de Meia-Idade , Feminino , Humanos , Fluxo de Trabalho , África do Sul , Espectrometria de Massas/métodos
4.
S Afr Med J ; 112(2): 13502, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35139990

RESUMO

BACKGROUND: Better integration of HIV and sexually transmitted infection (STI) prevention and treatment services is needed to accelerate progress towards the goal of zero new HIV infections. OBJECTIVES: To describe HIV positivity, antiretroviral therapy (ART) use, viral suppression and recency of HIV infection among symptomatic STI service attendees at two primary care clinics in South Africa. METHODS: In a cross-sectional study, male and female STI service attendees presenting with symptoms consistent with STI syndromes were enrolled following informed consent. An interviewer-administered questionnaire was completed and appropriate genital and blood specimens were collected for STI testing and HIV biomarker measurements including recency of infection and antiretroviral (ARV) drug levels. Descriptive statistics were used to describe enrolled attendees, and to determine the proportion of attendees who were HIV-positive, recently infected, taking ART and virally suppressed. HIV-positive attendees with detectable ARVs were considered to be on ART, while those with viral loads (VLs) ≤200 copies/mL were considered virally suppressed. RESULTS: Of 451 symptomatic attendees whose data were analysed, 93 (20.6%) were HIV-positive, with 15/93 (16.1%) being recently infected. Recent infection was independently associated with genital ulcer disease at presentation, especially ulcers with no detectable STI pathogens. Among the 78 (83.9%) with long-term infection, only 30 (38.5%) were on ART, with 23/30 (76.7%) virally suppressed. CONCLUSIONS: In a population at risk of HIV transmission, there was a high burden of recent infection and unsuppressed VLs. Incorporating pre-exposure prophylaxis, ART initiation and adherence support into STI services will be necessary for progress towards eliminating HIV transmission.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Carga Viral , Adulto , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Infecções Sexualmente Transmissíveis/terapia , África do Sul/epidemiologia , Inquéritos e Questionários , Adulto Jovem
5.
Regul Toxicol Pharmacol ; 128: 105095, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890761

RESUMO

Cleaning agents (CAs) are used in multipurpose facilities to control carryover contamination of active pharmaceutical ingredients (APIs) to scientifically justified limits. While this is often done with the PDE methodology used for API impurities, it is unclear if it is justifiable and necessary for cleaning agents, which generally represent a comparatively lower health risk. Comparing calculated oral PDE values for CA ingredients (CAIs) from four companies with PDEs of a selected number of small-molecule APIs showed that the toxicity of CAIs is several orders of magnitude lower. Furthermore, a critical review of the toxicity and everyday exposure to the general population of the main CAIs functional groups showed that the expected health risks are generally negligible. This is particularly true if the associated mode of actions cause local toxicity that is usually irrelevant at the concentration of potential residue carryover. This work points towards alternative approaches to the PDE concept to control CAIs' contamination and provides some guidance on grouping and identifying compounds with lower health risks based on exposure and mode of action reasoning. In addition, this work supports the concept that limit values should only be set for CAIs of toxicological concern.


Assuntos
Detergentes/toxicidade , Contaminação de Medicamentos/prevenção & controle , Indústria Farmacêutica/organização & administração , Detergentes/análise , Relação Dose-Resposta a Droga , Indústria Farmacêutica/normas , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/normas , Saúde Ocupacional , Medição de Risco
6.
Int J Tuberc Lung Dis ; 25(11): 896-902, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34686231

RESUMO

BACKGROUND: High-dose isoniazid (INHH) (15-20 mg/kg/day) could be administered to overcome low-level INH resistance, but pharmacokinetic data are sparse.METHODS: This observational study included South African children (<15 years) receiving INHH as preventive therapy, or treatment for multidrug-resistant TB (MDR-TB) exposure or disease. Pharmacokinetic sampling was performed after an INH dose of 20 mg/kg. Non-compartmental analysis and multivariable regression models were used to evaluate associations of key covariates with area under the curve (AUC0-24) and maximum concentration (Cmax). AUC and Cmax values were compared against proposed adult targets.RESULTS: Seventy-seven children were included, with median age of 3.7 years; 51 (66%) had MDR-TB disease and 26 (34%) had MDR-TB exposure. Five were HIV-positive, of whom four were ≥5 years old. The median AUC0-24 was 19.46 µgh/mL (IQR 10.76-50.06) and Cmax was 5.14 µg/mL (IQR 2.69-13.2). In multivariable analysis of children aged <5 years, MDR-TB disease (vs. exposure) was associated with considerably lower AUC0-24 (geometric mean ratio GMR 0.19, 95% CI 0.15-0.26; P < 0.001) and Cmax (GMR 0.20, 95% CI 0.15-0.26; P < 0.001).CONCLUSIONS: INH concentrations in children with MDR-TB disease were much lower than expected, but comparable to previous reports in children with MDR-TB exposure. Further studies should confirm these findings and explore possible causes.


Assuntos
Isoniazida , Tuberculose Resistente a Múltiplos Medicamentos , Adulto , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Humanos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
7.
Int J Tuberc Lung Dis ; 25(1): 36-42, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384043

RESUMO

BACKGROUND: Anti-TB drugs dosing based on weight alone may contribute to suboptimal drug concentrations and poor treatment outcomes in malnourished children. We examined the effect of malnutrition on the pharmacokinetics (PK) of first-line anti-TB drugs in children.METHODS: Drug concentrations were measured in Ghanaian children during the intensive phase of TB treatment. Weight-for-age (WFA), height-for-age (HFA), weight-for-height (WFH) and body mass index-for-age (BFA) were calculated and children with Z-scores < -2 SD (standard deviations) were considered as having malnutrition. PK differences of anti-TB drugs were compared by nutritional status.RESULTS: Of 100 participants, 24/48 (50.0%) of those younger than 5 years had wasting, 58/86 (67.4%) were underweight, and 56/99 (56.6%) had stunting; 22/51 (43.1%) children aged ≥5 years had low BFA. Children with stunting were more likely than controls to have lower mean peak concentration (Cmax) and area under the curve (AUC0-8h) of rifampin (RIF) and pyrazinamide (PZA), as well as a higher frequency of Cmax below the normal range. Wasting and underweight were associated with lower mean ethambutol (EMB) Cmax and AUC0-8h.CONCLUSIONS: The current WHO-recommended dosages were associated with lower plasma exposure of RIF, PZA and EMB in children with stunting, wasting and underweight. Anti-TB drugs dosing models for children may need to include height.


Assuntos
Desnutrição , Preparações Farmacêuticas , Tuberculose , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Gana/epidemiologia , Humanos , Desnutrição/epidemiologia , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia
8.
Parasitol Res ; 119(9): 3099-3104, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32627079

RESUMO

The first case of feline ocular Thelazia callipaeda infection and two new canine imported infections in West Germany are here described. The three animals had a history of recent travel to/from other countries. The young adult cat imported from Spain presented an intermittent unilateral ocular discharge. During in-depth ophthalmic examination, a single alive nematode was removed from the conjunctival compartment of the affected eye. Referring to the canine cases, an adult female dog originated from Kenya presented epiphora and mucous whitish-grey discharge of the right eye. During flushing of the nasolacrimal duct two small, thin and long nematodes were removed. Furthermore, a male Borzoi racing dog with regular visit to racing tracks in different countries presented ocular mucous discharge. At ophthalmologic examination, two transparent-whitish vital nematodes were removed. All nematode specimens of the three cases were morphologically identified as adult T. callipaeda parasites. The animals were treated orally with milbemycin oxime (2.0 mg/kg; cat) or milbemycin oxime/praziquantel (0.5 mg/kg and 5.0 mg/kg; dogs) twice with 1-week interval resulting in complete resolution of symptoms. The repeated introduction of patent T. callipaeda-infected animals, especially from southern and eastern endemic countries, will ease the establishment of ophthalmic thelaziosis in Northern Europe. The male fruit fly, Phortica variegata, an intermediate host of T. callipaeda, is endemic within European countries. Considering the clinical and zoonotic relevance of ophthalmic thelaziosis, enhanced disease awareness of European medical and veterinarian doctors and in-depth eye examination for proper detection of T. callipaeda are crucial for appropriate anthelmintic treatments and to limit spreading of the infection.


Assuntos
Doenças do Gato/parasitologia , Doenças do Cão/parasitologia , Infecções Oculares Parasitárias/parasitologia , Infecções por Spirurida/veterinária , Thelazioidea/isolamento & purificação , Animais , Anti-Helmínticos/administração & dosagem , Doenças do Gato/tratamento farmacológico , Gatos , Cães , Infecções Oculares Parasitárias/tratamento farmacológico , Feminino , Alemanha , Macrolídeos/administração & dosagem , Masculino , Infecções por Spirurida/tratamento farmacológico , Infecções por Spirurida/parasitologia , Thelazioidea/genética , Thelazioidea/fisiologia
9.
Int J Tuberc Lung Dis ; 23(10): 1068-1074, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31627771

RESUMO

SETTING: Treatment outcomes in multidrug-resistant tuberculosis (MDR-TB) are poor. Due to drug toxicity and a long treatment duration, approximately half of patients are treated successfully. Medication is often crushed for patients who have difficulty swallowing whole tablets. Whether crushing tablets affects drug exposure in MDR-TB treatment is not known.OBJECTIVE AND DESIGN: We performed a sequential pharmacokinetic study in patients aged >18 years on MDR-TB treatment at two hospitals in Cape Town, South Africa. We compared the bioavailability of pyrazinamide, moxifloxacin, isoniazid (INH), ethambutol and terizidone when the tablets were crushed and mixed with water before administration vs. swallowed whole. We sampled blood at six time points over 10 h under each condition separated by 2 weeks. Non-compartmental analysis was used to derive the key pharmacokinetic measurements.RESULTS: Twenty participants completed the study: 15 were men, and the median age was 31.5 years. There was a 42% reduction in the area under the curve AUC0-10 of INH when the tablets were crushed compared with whole tablets (geometric mean ratio 58%; 90%CI 47-73). Crushing tablets of pyrazinamide, moxifloxacin, ethambutol and terizidone did not affect the bioavailability significantly.CONCLUSION: We recommend that crushing of INH tablets in the MDR-TB treatment regimen be avoided. Paediatric INH formulations may be a viable alternative if the crushing of INH tablets is indicated.


Assuntos
Antituberculosos/administração & dosagem , Isoniazida/administração & dosagem , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Antituberculosos/química , Antituberculosos/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Feminino , Humanos , Isoniazida/química , Isoniazida/farmacocinética , Masculino , Comprimidos , Resultado do Tratamento
10.
Patient Educ Couns ; 102(4): 663-669, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30448043

RESUMO

Objectives This study aims to assess medical students' interest in a Motivational Interviewing (MI), the objective need for a special training, and students' satisfaction with and the effectiveness of such a course. Methods A mandatory MI course was implemented for sixth-semester medical students. Their interest in learning MI was evaluated, along with their satisfaction with the course, which was delivered in a blended-learning teaching approach. Participants' baseline MI skills and general communication skills were assessed. MI non-adherent behavior, like persuading and confronting patients, was noted. Successful learning was measured with a multiple-choice test administered before and after the course that assessed subjective knowledge and skills. Results Students were highly interested in learning MI. At baseline, they showed good communication skills but moderate MI skills. Satisfaction with the course was high. The course was effective, as subjective and objective knowledge and skills improved significantly. Conclusions This pilot study suggests that basic MI skills can be successfully taught in a blended-learning teaching approach. Further research should investigate sustainability and transfer to clinical practice. Practice implications Medical schools should consider providing students with special training in MI to help students counsel patients towards behavioral changes.


Assuntos
Terapia Comportamental/educação , Competência Clínica , Comunicação , Aconselhamento/educação , Educação de Graduação em Medicina/métodos , Entrevista Motivacional/métodos , Estudantes de Medicina/psicologia , Adolescente , Adulto , Aconselhamento/normas , Currículo , Avaliação Educacional , Feminino , Alemanha , Humanos , Aprendizagem , Masculino , Projetos Piloto , Inquéritos e Questionários
11.
Int J Tuberc Lung Dis ; 22(8): 926-930, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29991403

RESUMO

SETTING: Reducing pain from intramuscular injection of kanamycin (KM) could improve the tolerability of multidrug-resistant tuberculosis (MDR-TB) treatment. Lidocaine has been shown to be an effective anaesthetic diluent for some intramuscular injections, but has not been investigated with KM in the treatment of adult patients with MDR-TB. OBJECTIVE AND DESIGN: We performed a randomised single-blinded crossover study to determine if lidocaine reduces KM injection-site pain. We recruited patients aged 18 years on MDR-TB treatment at two TB hospitals in Cape Town, South Africa. KM pharmacokinetic parameters and a validated numeric pain scale were used at intervals over 10 h following the injection of KM with and without lidocaine on two separate occasions. RESULTS: Twenty participants completed the study: 11 were males, the median age was 36 years, 11 were HIV-infected, and the median body mass index was 17.5 kg/m2. The highest pain scores occurred early, and the median pain score was 0 by 30 min. The use of lidocaine with KM significantly reduced pain at the time of injection and 15 min post-dose. On multiple regression analysis, lidocaine halved pain scores (adjusted OR 0.5, 95%CI 0.3-0.9). The area under the curve at 0-10 h of KM with and without lidocaine was respectively 147.7 and 143.6 µg·h/ml. CONCLUSION: Lidocaine significantly reduces early injection-site pain and has no effect on KM pharmacokinetics.


Assuntos
Anestésicos Locais/administração & dosagem , Canamicina/farmacocinética , Lidocaína/administração & dosagem , Dor Processual/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Estudos Cross-Over , Feminino , Infecções por HIV/complicações , Humanos , Injeções Intramusculares/efeitos adversos , Canamicina/administração & dosagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Método Simples-Cego , África do Sul , Tuberculose Resistente a Múltiplos Medicamentos/complicações
12.
Int J Tuberc Lung Dis ; 22(5): 537-543, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29663959

RESUMO

SETTING: Rifampicin (RMP) drives treatment response in drug-susceptible tuberculosis. Low RMP concentrations increase the risk of poor outcomes, and drug quality needs to be excluded as a contributor to low RMP exposure. OBJECTIVES AND DESIGN: We performed an open-label, three-way cross-over study of three licensed RMP-containing formulations widely used in South Africa to evaluate the bioavailability of RMP in a two-drug fixed-dose combination tablet (2FDC) and a four-drug FDC (4FDC) against a single-drug reference. RMP dosed at 600 mg was administered 2 weeks apart in random sequence. Plasma RMP concentrations were measured pre-dose and 1, 2, 3, 4, 6, 8 and 12 h post-dose. The area under the concentration-time curve (AUC0-12) of the FDCs was compared to the single drug reference. Simulations were used to predict the impact of our findings. RESULTS: Twenty healthy volunteers (median age 22.8 years, body mass index 24.2 kg/m2) completed the study. The AUC0-12 of the 4FDC/reference (geometric mean ratio [GMR] 78%, 90%CI 69-89) indicated an average 20% reduction in RMP bioavailability in the 4FDC. The 2FDC/reference (GMR 104%, 90%CI 97-111) was bioequivalent. Simulations suggested dose adjustments to compensate for the poor bioavailability of RMP with the 4FDC, and revised weight-band doses to prevent systematic underdosing of low-weight patients. CONCLUSION: Post-marketing surveillance of in vivo bioavailability of RMP and improved weight band-based dosing are recommended.


Assuntos
Antituberculosos/farmacocinética , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Adulto , Antituberculosos/normas , Disponibilidade Biológica , Estudos Cross-Over , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Rifampina/normas , África do Sul , Comprimidos , Equivalência Terapêutica , Adulto Jovem
13.
Int J Tuberc Lung Dis ; 22(1): 30-33, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29297422

RESUMO

SETTING: Terizidone/cycloserine (TRD/CS) is included in standard treatment regimens for multidrug-resistant tuberculosis (MDR-TB) in many countries. The steady state pharmacokinetics (PKs) of CS after TRD administration are not known. OBJECTIVES AND DESIGN: We recruited in-patients treated with 250-750 mg oral TRD daily as part of standard treatment regimens for pulmonary MDR-TB in Cape Town, South Africa. Plasma CS assays were performed in samples taken pre-dose and at 2, 4, 6, 8 and 10 h post-dose. CS concentrations were measured using a validated liquid chromatography-tandem mass spectrometry method. Non-compartmental PK analyses were performed. RESULTS: Of 35 participants enrolled, 22 were males, and 20 (57%) were infected with the human immunodeficiency virus; the median age was 37 years. The median duration on TRD at the time of sampling was 33 days (interquartile range [IQR] 28-39). The area under the concentration-time curve at 0-10 h (AUC0-10) was 319 µg.h/ml (IQR 267.5-378.7), and peak concentration was 38.1 µg/ml (IQR 32.6-47.2). On multiple regression, dose (mg/kg) was the only factor independently associated with AUC0-10. CONCLUSION: Steady state concentrations of CS in patients treated with TRD for MDR-TB were higher than those reported with CS formulations. Our findings support once-daily dosing.


Assuntos
Antituberculosos/administração & dosagem , Ciclosserina/farmacocinética , Isoxazóis/administração & dosagem , Oxazolidinonas/administração & dosagem , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adulto , Antituberculosos/farmacocinética , Área Sob a Curva , Cromatografia Líquida , Feminino , Infecções por HIV/epidemiologia , Humanos , Isoxazóis/farmacocinética , Masculino , Pessoa de Meia-Idade , Oxazolidinonas/farmacocinética , Estudos Prospectivos , Análise de Regressão , África do Sul , Espectrometria de Massas em Tandem
14.
S Afr Med J ; 107(10): 887-891, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-29022534

RESUMO

BACKGROUND: Non-adherence to antihypertensives is a cause of 'pseudo-treatment-resistant' hypertension. OBJECTIVE: To determine whether monitoring plasma amlodipine concentrations and inhibition of angiotensin-converting enzyme (ACE) can be adjunct adherence tools. METHODS: Patients with hypertension who were prescribed enalapril and amlodipine were enrolled. Blood pressures (BPs) were monitored and an adherence questionnaire was completed. Steady-state amlodipine was assayed using liquid chromatography-mass spectrometry and degree of ACE inhibition using the Z-FHL/HHL (z-phenylalanine-histidine-leucine/hippuryl-histidine-leucine) ratio. RESULTS: One hundred patients (mean (standard deviation) age 50.5 (12) years, 46% male) were enrolled. Based on plasma assays, 26/97 patients (26.8%) were unsuppressed by enalapril and 20/100 (20%) were sub-therapeutic for amlodipine. There were significant BP differences based on plasma levels of the medication: 21/20 mmHg lower in the group with suppressed ACE and 26/20 mmHg in the group with steady-state amlodipine concentrations. CONCLUSIONS: Monitoring antihypertensive adherence by assaying plasma medication concentrations is a feasible option for evaluating true v. pseudo-resistant hypertension.

15.
Int J Tuberc Lung Dis ; 20(7): 915-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27287644

RESUMO

SETTING: To assess the revised World Health Organization-recommended dose of 10-20 mg/kg rifampicin (RMP), we studied the steady state pharmacokinetics of RMP in South African children who received standard treatment for drug-susceptible tuberculosis (TB). OBJECTIVE: To determine the formulation effect on the pharmacokinetics of RMP. DESIGN: RMP plasma concentrations were characterised in 146 children (median age 1.4 years, range 0.2-10.2). The morning dose on the day of the pharmacokinetic evaluation was administered as one of two RMP single-drug oral suspensions. RESULTS: While one formulation achieved 2 h concentrations in the range of those observed in adults (median 6.54 mg/l, interquartile range [IQR] 4.47-8.84), the other attained a median bioavailability of only 25% of this, with a median 2 h concentration of 1.59 mg/l (IQR 0.89-2.38). CONCLUSION: RMP is a key drug for the treatment of TB. It is critical that the quality of RMP suspensions used to treat childhood TB is ensured.


Assuntos
Antibióticos Antituberculose/farmacocinética , Aprovação de Drogas , Licenciamento , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Administração Oral , Antibióticos Antituberculose/administração & dosagem , Antibióticos Antituberculose/química , Antibióticos Antituberculose/normas , Disponibilidade Biológica , Criança , Pré-Escolar , Composição de Medicamentos , Monitoramento de Medicamentos , Feminino , Humanos , Lactente , Licenciamento/normas , Masculino , Soluções Farmacêuticas , Garantia da Qualidade dos Cuidados de Saúde , Controle de Qualidade , Rifampina/administração & dosagem , Rifampina/química , Rifampina/normas , África do Sul , Tuberculose/sangue , Tuberculose/diagnóstico
16.
Ther Innov Regul Sci ; 50(2): 155-168, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27042398

RESUMO

The Health and Environmental Sciences Institute (HESI) Developmental and Reproductive Toxicology Technical Committee sponsored a pharmaceutical industry survey on current industry practices for contraception use during clinical trials. The objectives of the survey were to improve our understanding of the current industry practices for contraception requirements in clinical trials, the governance processes set up to promote consistency and/or compliance with contraception requirements, and the effectiveness of current contraception practices in preventing pregnancies during clinical trials. Opportunities for improvements in current practices were also considered. The survey results from 12 pharmaceutical companies identified significant variability among companies with regard to contraception practices and governance during clinical trials. This variability was due primarily to differences in definitions, areas of scientific uncertainty or misunderstanding, and differences in company approaches to enrollment in clinical trials. The survey also revealed that few companies collected data in a manner that would allow a retrospective understanding of the reasons for failure of birth control during clinical trials. In this article, suggestions are made for topics where regulatory guidance or scientific publications could facilitate best practice. These include provisions for a pragmatic definition of women of childbearing potential, guidance on how animal data can influence the requirements for male and female birth control, evidence-based guidance on birth control and pregnancy testing regimes suitable for low- and high-risk situations, plus practical methods to ascertain the risk of drug-drug interactions with hormonal contraceptives.

17.
Antimicrob Agents Chemother ; 60(4): 2171-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26810651

RESUMO

There are limited pharmacokinetic data for use of the first-line antituberculosis drugs during infancy (<12 months of age), when drug disposition may differ. Intensive pharmacokinetic sampling was performed in infants routinely receiving antituberculosis treatment, including rifampin, isoniazid, pyrazinamide, and ethambutol, using World Health Organization-recommended doses. Regulatory-approved single-drug formulations, including two rifampin suspensions, were used on the sampling day. Assays were conducted using liquid chromatography-mass spectrometry; pharmacokinetic parameters were generated using noncompartmental analysis. Thirty-nine infants were studied; 14 (36%) had culture-confirmed tuberculosis. Fifteen (38%) were premature (<37 weeks gestation); 5 (13%) were HIV infected. The mean corrected age and weight were 6.6 months and 6.45 kg, respectively. The mean maximum plasma concentrations (Cmax) for rifampin, isoniazid, pyrazinamide, and ethambutol were 2.9, 7.9, 41.9, and 1.3 µg/ml, respectively (current recommended adult target concentrations: 8 to 24, 3 to 6, 20 to 50, and 2 to 6 µg/ml, respectively), and the mean areas under the concentration-time curves from 0 to 8 h (AUC0-8) were 12.1, 24.7, 239.4, and 5.1 µg · h/ml, respectively. After adjusting for age and weight, rifampin exposures for the two formulations used differed inCmax(geometric mean ratio [GMR],2.55; 95% confidence interval [CI], 1.47 to 4.41;P= 0.001) and AUC0-8(GMR, 2.52; 95% CI, 1.34 to 4.73;P= 0.005). HIV status was associated with lower pyrazinamideCmax(GMR, 0.85; 95% CI, 0.75 to 0.96;P= 0.013) and AUC0-8(GMR, 0.79; 95% CI, 0.69 to 0.90;P< 0.001) values. No other important differences were observed due to age, weight, prematurity, ethnicity, or gender. In summary, isoniazid and pyrazinamide concentrations in infants compared well with proposed adult target concentrations; ethambutol concentrations were lower but similar to previously reported pediatric studies. The low rifampin exposures require further investigation. (This study has been registered at ClinicalTrials.gov under registration no. NCT01637558.).


Assuntos
Antibacterianos/farmacocinética , Etambutol/farmacocinética , Isoniazida/farmacocinética , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinamida/farmacocinética , Rifampina/farmacocinética , Tuberculose Pulmonar/tratamento farmacológico , Antibacterianos/sangue , Antibacterianos/uso terapêutico , Área Sob a Curva , Coinfecção , Cálculos da Dosagem de Medicamento , Etambutol/sangue , Etambutol/uso terapêutico , Feminino , HIV/efeitos dos fármacos , HIV/crescimento & desenvolvimento , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Lactente , Recém-Nascido , Isoniazida/sangue , Isoniazida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/crescimento & desenvolvimento , Guias de Prática Clínica como Assunto , Pirazinamida/sangue , Pirazinamida/uso terapêutico , Rifampina/sangue , Rifampina/uso terapêutico , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/microbiologia
18.
BMC Infect Dis ; 16: 30, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26818566

RESUMO

BACKGROUND: Artemether-lumefantrine is currently the most widely recommended treatment of uncomplicated malaria. Lopinavir-based antiretroviral therapy is the commonly recommended second-line HIV treatment. Artemether and lumefantrine are metabolised by cytochrome P450 isoenzyme CYP3A4, which lopinavir/ritonavir inhibits, potentially causing clinically important drug-drug interactions. METHODS: An adaptive, parallel-design safety and pharmacokinetic study was conducted in HIV-infected (malaria-negative) patients: antiretroviral-naïve and those stable on lopinavir/ritonavir-based antiretrovirals. Both groups received the recommended six-dose artemether-lumefantrine treatment. The primary outcome was day-7 lumefantrine concentrations, as these correlate with antimalarial efficacy. Adverse events were solicited throughout the study, recording the onset, duration, severity, and relationship to artemether-lumefantrine. RESULTS: We enrolled 34 patients. Median day-7 lumefantrine concentrations were almost 10-fold higher in the lopinavir than the antiretroviral-naïve group [3170 versus 336 ng/mL; p = 0.0001], with AUC(0-inf) and Cmax increased five-fold [2478 versus 445 µg.h/mL; p = 0.0001], and three-fold [28.2 versus 8.8 µg/mL; p < 0.0001], respectively. Lumefantrine Cmax, and AUC(0-inf) increased significantly with mg/kg dose in the lopinavir, but not the antiretroviral-naïve group. While artemether exposure was similar between groups, Cmax and AUC(0-8h) of its active metabolite dihydroartemisinin were initially two-fold higher in the lopinavir group [p = 0.004 and p = 0.0013, respectively]. However, this difference was no longer apparent after the last artemether-lumefantrine dose. Within 21 days of starting artemether-lumefantrine there were similar numbers of treatment emergent adverse events (42 vs. 35) and adverse reactions (12 vs. 15, p = 0.21) in the lopinavir and antiretroviral-naïve groups, respectively. There were no serious adverse events and no difference in electrocardiographic QTcF- and PR-intervals, at the predicted lumefantrine Tmax. CONCLUSION: Despite substantially higher lumefantrine exposure, intensive monitoring in our relatively small study raised no safety concerns in HIV-infected patients stable on lopinavir-based antiretroviral therapy given the recommended artemether-lumefantrine dosage. Increased day-7 lumefantrine concentrations have been shown previously to reduce the risk of malaria treatment failure, but further evidence in adult patients co-infected with malaria and HIV is needed to assess the artemether-lumefantrine risk : benefit profile in this vulnerable population fully. Our antiretroviral-naïve patients confirmed previous findings that lumefantrine absorption is almost saturated at currently recommended doses, but this dose-limited absorption was overcome in the lopinavir group. TRIAL REGISTRATION: Clinical Trial Registration number NCT00869700. Registered on clinicaltrials.gov 25 March 2009.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/farmacocinética , Artemeter , Artemisininas/efeitos adversos , Artemisininas/farmacocinética , Artemisininas/uso terapêutico , Interações Medicamentosas , Etanolaminas/efeitos adversos , Etanolaminas/farmacocinética , Etanolaminas/uso terapêutico , Feminino , Fluorenos/efeitos adversos , Fluorenos/farmacocinética , Fluorenos/uso terapêutico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Lopinavir/efeitos adversos , Lopinavir/farmacocinética , Lopinavir/uso terapêutico , Lumefantrina , Masculino , Ritonavir/efeitos adversos , Ritonavir/farmacocinética , Ritonavir/uso terapêutico
19.
Clin Exp Dermatol ; 41(2): 196-201, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26211494

RESUMO

BACKGROUND: The topical steroids betamethasone (BM) and clobetasol propionate (CP) are illegal in cosmetics. Hydroquinone (HQ) and mercury (Hg) are either illegal or allowed only in limited concentrations (2% and 1 ppm, respectively). AIM: To investigate active ingredients and countries of origin of popular skin-lightening products available in Cape Town, South Africa. METHODS: In total, 29 products were examined; of these, 22 products were purchased from informal vendors, and 2 products (out of a total of 29) were purchased over the counter. HQ, Hg(2+) and steroids were quantified by high-performance liquid chromatography-ultraviolet spectrophotometry, inductively coupled plasma-mass spectrometry and liquid chromatography-mass spectrometry, respectively. RESULTS: Of the 29 products, 22 (75.9%), all imported and bought from informal vendors, contained illegal or banned ingredients: 13 (44.8%) contained steroids (9 CP, 4 BM), 12 (41.4%) contained Hg (30-2300 ppm), and 11 (37.9%) contained HQ. Sequentially, the products originated from Italy (27.3%, n = 6), India (22.7%, n = 5), the Democratic Republic of Congo (DRC) (22.7%, n = 5), Cote d'Ivoire (9.1%, n = 2), USA (9.1%, n = 2), UK (4.5%, n = 1) and France (4.5%, n = 1). Two products, one from India and one from the DRC, contained all four ingredients (HQ, Hg, BM, CP). Of the 12 products containing Hg, 10 also contained HQ and/or a steroid, yet none listed Hg as an ingredient. A significant proportion of the steroid-containing products (76.9%) also contained at least one other skin-lightening agent. Not all internationally available products were tested, which is a limitation of the study. CONCLUSION: In spite of a European Union ban on skin lighteners, a third of the products tested were from Europe. Combinations of Hg and ultrapotent steroids were prominent. International law enforcement and random testing is needed to encourage industry compliance and help protect consumers.


Assuntos
Hidroquinonas/análise , Mercúrio/análise , Preparações Clareadoras de Pele/química , Esteroides/análise , Betametasona/análise , Cromatografia Líquida de Alta Pressão , Clobetasol/análise , Espectrometria de Massas , Pironas/análise , África do Sul , Espectrofotometria Ultravioleta
20.
Int J Tuberc Lung Dis ; 19(10): 1194-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26459532

RESUMO

Isoniazid preventive therapy is recommended in patients on antiretroviral treatment (ART) with latent tuberculous infection to prevent progression to active tuberculosis disease. Isoniazid (INH) inhibits cytochrome (CY) P3A4, which metabolises lopinavir (LPV). The administration of INH may cause higher LPV concentrations, which may increase LPV toxicity. LPV bioavailability is increased by co-formulated ritonavir (r), which may enhance the interaction of INH on LPV. We studied the effect of INH on LPV concentrations by administering INH for 7 days and performing intensive pharmacokinetic sampling in 16 human immunodeficiency virus infected patients established on LPV/r-based ART. INH did not significantly increase steady-state LPV area under the plasma concentration-time curve calculated for the 12 h-dosing interval.


Assuntos
Fármacos Anti-HIV/farmacocinética , Antituberculosos/farmacologia , Isoniazida/farmacologia , Lopinavir/farmacocinética , Ritonavir/farmacocinética , Adulto , Fármacos Anti-HIV/administração & dosagem , Antituberculosos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Progressão da Doença , Combinação de Medicamentos , Interações Medicamentosas , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Isoniazida/administração & dosagem , Tuberculose Latente/tratamento farmacológico , Lopinavir/administração & dosagem , Masculino , Ritonavir/administração & dosagem , África do Sul
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