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1.
Malar J ; 22(1): 199, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37381013

RESUMO

BACKGROUND: Evaluation of parasite clearance patterns in experimental human infection trials helps increase understanding of drug action. In a previously reported phase Ib trial of a new investigational anti-malarial drug M5717, parasite clearance showed a biphasic linear pattern: slow removal phase with a near flat clearance rate followed by a fast clearance phase with a steep slope. In this study three statistical approaches were implemented and compared to estimate the parasite clearance rate for each phase and the time point corresponding to the change of clearance rates (changepoint between the two phases). METHODS: Data using three M5717 doses 150 mg (n = 6), 400 mg (n = 8), 800 mg (n = 8) were used to estimate biphasic clearance rates. Three models were investigated: firstly, segmented mixed models with estimated changepoint-models with/without random effects in various parameters were compared. Secondly, a segmented mixed model using grid search-this method is similar to the first except that changepoints were not estimated, instead they were selected based on model fit from given candidate values. Thirdly, a two-stage approach whereby a segmented regression model fit to each participant followed by a meta-analysis method. Hourly rate of parasite clearance (HRPC) interpreted as the percentage of parasites removed each hour was calculated. RESULTS: The three models generated similar results. Using segmented mixed models, the estimated changepoints after treatment in hours (95% CI) were: 150 mg: 33.9 (28.7, 39.1); 400 mg: 57.4 (52.5, 62.4); and 800 mg: 52.8 (47.4, 58.1). For all three treatment groups, there was nearly no clearance before the changepoints, but rapid clearance in the second phase (HRPC [95% CI]): 150 mg: 16.8% (14.3, 19.1%); 400 mg: 18.6% (16.0, 21.1%); and 800 mg: 11.7% (9.3, 14.1%). CONCLUSIONS: All three statistical approaches are effective tools to characterize the bi-phasic clearance of M5717 in the phase 1b experimental Plasmodium falciparum malaria human infection study. The statistical approaches produced similar results to estimate the two-phase clearance rates and the changepoint for each treatment dose of M5717. However, the segmented mixed model with random changepoints has several advantages: it is computationally efficient, provides precision for changepoint estimates and is robust concerning outlying datapoints or individuals.


Assuntos
Antimaláricos , Malária Falciparum , Parasitos , Humanos , Animais , Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Cinética
2.
Toxicol Appl Pharmacol ; 443: 116006, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35367236

RESUMO

M5717 is a novel drug inhibiting synthesis of elongation factor 2 (PeEF2) in Plasmodium species, showing potent anti-malarial activity in preclinical studies. Traditional daily-dosing animal experiments estimating maximum safe starting dose for a first-in-human study ('no observed adverse effect level'; NOAEL) were unsuccessful due to the long pharmacokinetic half-life of M5717, causing significant drug accumulation and high exposure. This study describes an innovative strategy to produce a GLP-certified toxicology package and estimate NOAEL for long-lasting molecules like M5717. Simulated pharmacokinetic/toxicokinetic profiles were used to design the dosing schedule for preclinical safety studies and to determine the 14-day total exposure. Animals (rats/dogs) were administered various doses of M5717 using an intermittent dosing schedule allowing partial drug elimination and alleviation of toxicity during off-treatment days to maintain a minimal parasitical concentration (MPC) of 10 ng/mL; subsequently animals were monitored for toxicity and mortality. Results showed good correlation to the modelled data used to design the dosing regimen and required MPC was reached for M5717 in study animals and could be used to calculate NOAEL. This fit-for-purpose study design allowed for maintaining clinically relevant exposure to M5717, whilst minimizing toxicity-causing compound accumulation, an aspect unaddressed by traditional NOAEL-estimating experiments. This is the first time that a compound-specific, species-specific, kinetic model-based approach to preclinical study design for regulatory toxicology studies has been described and applied to an antimalarial drug candidate with long pharmacokinetic half-life. It has potential for application to other drugs with long half-lives, supporting their clinical development.


Assuntos
Antimaláricos , Plasmodium , Animais , Antimaláricos/toxicidade , Cães , Nível de Efeito Adverso não Observado , Fator 2 de Elongação de Peptídeos , Ratos , Projetos de Pesquisa
3.
Malar J ; 21(1): 151, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35570264

RESUMO

BACKGROUND: Targeting the asymptomatic liver stage of Plasmodium infection through chemoprevention could become a key intervention to reduce malaria-associated incidence and mortality. METHODS: M5717, a Plasmodium elongation factor 2 inhibitor, was assessed in vitro and in vivo with readily accessible Plasmodium berghei parasites. In an animal refinement, reduction, replacement approach, the in vitro IC99 value was used to feed a Population Pharmacokinetics modelling and simulation approach to determine meaningful effective doses for a subsequent Plasmodium sporozoite-induced volunteer infection study. RESULTS: Doses of 100 and 200 mg would provide exposures exceeding IC99 in 96 and 100% of the simulated population, respectively. CONCLUSIONS: This approach has the potential to accelerate the search for new anti-malarials, to reduce the number of healthy volunteers needed in a clinical study and decrease and refine the animal use in the preclinical phase.


Assuntos
Antimaláricos , Malária , Animais , Antimaláricos/farmacocinética , Antimaláricos/uso terapêutico , Humanos , Fígado/parasitologia , Malária/tratamento farmacológico , Malária/parasitologia , Malária/prevenção & controle , Fator 2 de Elongação de Peptídeos , Plasmodium berghei
4.
BMC Infect Dis ; 21(1): 1274, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930178

RESUMO

BACKGROUND: The development of novel malaria vaccines and antimalarial drugs is limited partly by emerging challenges to conduct field trials in malaria endemic areas, including unknown effects of existing immunity and a reported fall in malaria incidence. As a result, Controlled Human Malaria Infection (CHMI) has become an important approach for accelerated development of malarial vaccines and drugs. We conducted a systematic review of the literature to establish aggregate evidence on the reproducibility of a malaria sporozoite challenge model. METHODS: A systematic review of research articles published between 1990 and 2018 on efficacy testing of malaria vaccines and drugs using sporozoite challenge and sporozoite infectivity studies was conducted using Pubmed, Scopus, Embase and Cochrane Library, ClinicalTrials.gov and Trialtrove. The inclusion criteria were randomized and non-randomized, controlled or open-label trials using P. falciparum or P. vivax sporozoite challenges. The data were extracted from articles using standardized data extraction forms and descriptive analysis was performed for evidence synthesis. The endpoints considered were infectivity, prepatent period, parasitemia and safety of sporozoite challenge. RESULTS: Seventy CHMI trials conducted with a total of 2329 adult healthy volunteers were used for analysis. CHMI was induced by bites of mosquitoes infected with P. falciparum or P. vivax in 52 trials and by direct venous inoculation of P. falciparum sporozoites (PfSPZ challenge) in 18 trials. Inoculation with P. falciparum-infected mosquitoes produced 100% infectivity in 40 studies and the mean/median prepatent period assessed by thick blood smear (TBS) microscopy was ≤ 12 days in 24 studies. On the other hand, out of 12 infectivity studies conducted using PfSPZ challenge, 100% infection rate was reproduced in 9 studies with a mean or median prepatent period of 11 to 15.3 days as assessed by TBS and 6.8 to 12.6 days by PCR. The safety profile of P. falciparum and P.vivax CHMI was characterized by consistent features of malaria infection. CONCLUSION: There is ample evidence on consistency of P. falciparum CHMI models in terms of infectivity and safety endpoints, which supports applicability of CHMI in vaccine and drug development. PfSPZ challenge appears more feasible for African trials based on current evidence of safety and efficacy.


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Preparações Farmacêuticas , Adulto , Animais , Humanos , Malária Falciparum/prevenção & controle , Reprodutibilidade dos Testes , Esporozoítos
5.
J Pharmacokinet Pharmacodyn ; 45(5): 747-762, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30218416

RESUMO

L-praziquantel (PZQ) pharmacokinetic data were analyzed from two relative bioavailability Phase 1 studies in adult, healthy subjects with two new oral dispersion tablet (ODT) formulations of L-PZQ administered under various combinations of co-administration with food, water, and/or crushing. Linear mixed effects models adequately characterized the noncompartmental estimates of the pharmacokinetic profiles in both studies. Dose, food, and formulation were found to significantly affect L-PZQ exposure in both studies. The model for AUC was then extrapolated to children 2-5 years old accounting for enzyme maturation and weight. The predicted exposures were compared to an external Phase 1 study conducted by the Swiss Tropical and Public Health Institute using a currently marketed formulation (Cesol 600 mg immediate-release tablets) and found to be substantially lower than observed. A root cause analysis was completed to identify the reason for failure of the models. Various scenarios were proposed and tested. Two possible reasons for the failure were identified. One reason was that the model did not account for the reduced hepatic clearance seen in patients compared to the healthy volunteer population used to build the model. The second possible reason was that PZQ absorption appears sensitive to meal composition and the model did not account for differences in meals between a standardized Phase 1 unit and clinical sites in Africa. Further studies are needed to confirm our hypotheses.


Assuntos
Praziquantel/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Pré-Escolar , Estudos Cross-Over , Voluntários Saudáveis , Humanos , Masculino , Comprimidos/farmacocinética , Equivalência Terapêutica , Adulto Jovem
6.
Reprod Med Biol ; 17(1): 52-58, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29371821

RESUMO

Purpose: Recombinant hCG (r-hCG) was approved in Japan in 2016. As a prerequisite for a Phase III study in Japan related to this approval, the pharmacokinetic (PK) profile of r-hCG was investigated. Methods: An open-label, partly randomized, single-center, single-dose, group-comparison, Phase I PK-bridging study was done that compared a single 250 µg dose of r-hCG with a single 5000 IU dose of urinary hCG (u-hCG) in healthy Japanese women, as well as comparing a single 250 µg dose of r-hCG in Japanese and Caucasian women. The Japanese participants were randomized 1:1 to receive either r-hCG or u-hCG, while the Caucasian participants were weight-matched to the Japanese participants who were receiving r-hCG in a 1:1 fashion. The primary PK parameters were the area under the serum concentration-time curve from time 0 extrapolated to infinity (AUC 0-∞) and the maximum serum concentration (Cmax). Results: The mean serum hCG concentration-time profiles of r-hCG in the Japanese and Caucasian participants were a similar shape, but the level of overall exposure was ~20% lower in the Japanese participants. For the Japanese participants, r-hCG resulted in an 11% lower Cmax but a 19% higher AUC 0-∞ compared with u-hCG. No new safety signal was identified. Conclusion: This study cannot exclude a potential difference in the PK profile of r-hCG between Japanese and Caucasian participants. However, this study does not indicate that there are clinically relevant differences in the serum PK of r-hCG and u-hCG in the Japanese participants.

7.
Lancet Infect Dis ; 23(7): 867-876, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36893784

RESUMO

BACKGROUND: WHO has underlined the need for a child-friendly treatment for schistosomiasis, a prevalent parasitic disease in low-income and middle-income countries. After successful phase 1 and 2 trials, we aimed to evaluate the efficacy, safety, palatability, and pharmacokinetics of arpraziquantel (L-praziquantel) orodispersible tablets for preschool-aged children. METHODS: This open-label, partly randomised, phase 3 study was conducted at two hospitals in Côte d'Ivoire and Kenya. Children with a minimum bodyweight of 5 kg in those aged 3 months to 2 years and 8 kg in those aged 2-6 years were eligible. In cohort 1, participants aged 4-6 years infected with Schistosoma mansoni were randomly assigned (2:1) to receive a single dose of oral arpraziquantel 50 mg/kg (cohort 1a) or oral praziquantel 40 mg/kg (cohort 1b) using a computer-generated randomisation list. Cohorts 2 (aged 2-3 years) and 3 (aged 3 months to 2 years) infected with S mansoni, and the first 30 participants in cohort 4a (aged 3 months to 6 years) infected with Schistosoma haematobium, received a single dose of oral arpraziquantel 50 mg/kg. After follow-up assessments, arpraziquantel was increased to 60 mg/kg (cohort 4b). Laboratory personnel were masked to the treatment group, screening, and baseline values. S mansoni was detected using a point-of-care circulating cathodic antigen urine cassette test and confirmed using the Kato-Katz method. The primary efficacy endpoint was clinical cure rate at 17-21 days after treatment in cohorts 1a and 1b, measured in the modified intention-to-treat population and calculated using the Clopper-Pearson method. This study is registered with ClinicalTrials.gov, NCT03845140. FINDINGS: Between Sept 2, 2019, and Aug 7, 2021, 2663 participants were prescreened and 326 were diagnosed with S mansoni or S haematobium. 288 were enrolled (n=100 in cohort 1a, n=50 in cohort 1b, n=30 in cohort 2, n=18 in cohort 3, n=30 in cohort 4a, and n=60 in cohort 4b), but eight participants received antimalarial drugs and were excluded from the efficacy analyses. The median age was 5·1 years (IQR 4·1-6·0) and 132 (47%) of 280 participants were female and 148 (53%) were male. Cure rates with arpraziquantel were similar to those with praziquantel (87·8% [95% CI 79·6-93·5] in cohort 1a vs 81·3% [67·4-91·1] in cohort 1b). No safety concerns were identified during the study. The most common drug-related treatment-emergent adverse events were abdominal pain (41 [14%] of 288 participants), diarrhoea (27 [9%]), vomiting (16 [6%]), and somnolence (21 [7%]). INTERPRETATION: Arpraziquantel, a first-line orodispersible tablet, showed high efficacy and favourable safety in preschool-aged children with schistosomiasis. FUNDING: The Global Health Innovative Technology Fund, the European and Developing Countries Clinical Trials Partnership, and the healthcare business of Merck KGaA, Darmstadt, Germany (CrossRef Funder ID: 10.13039/100009945).


Assuntos
Anti-Helmínticos , Esquistossomose mansoni , Esquistossomose , Animais , Pré-Escolar , Masculino , Feminino , Humanos , Praziquantel/efeitos adversos , Côte d'Ivoire , Quênia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/prevenção & controle , Anti-Helmínticos/efeitos adversos , Schistosoma mansoni , Esquistossomose/tratamento farmacológico
8.
Lancet Infect Dis ; 23(10): 1164-1174, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37414066

RESUMO

BACKGROUND: Cabamiquine is a novel antimalarial that inhibits Plasmodium falciparum translation elongation factor 2. We investigated the causal chemoprophylactic activity and dose-exposure-response relationship of single oral doses of cabamiquine following the direct venous inoculation (DVI) of P falciparum sporozoites in malaria-naive, healthy volunteers. METHODS: This was a phase 1b, randomised, double-blind, placebo-controlled, adaptive, dose-finding, single-centre study performed in Leiden, Netherlands. Malaria-naive, healthy adults aged 18-45 years were divided into five cohorts and randomly assigned (3:1) to receive cabamiquine or placebo. Randomisation was done by an independent statistician using codes in a permuted block schedule with a block size of four. Participants, investigators, and study personnel were masked to treatment allocation. A single, oral dose regimen of cabamiquine (200, 100, 80, 60, or 30 mg) or matching placebo was administered either at 2 h (early liver-stage) or 96 h (late liver-stage) after DVI. The primary endpoints based on a per-protocol analysis set were the number of participants who developed parasitaemia within 28 days of DVI, time to parasitaemia, number of participants with documented parasite blood-stage growth, clinical symptoms of malaria, and exposure-efficacy modelling. The impact of cabamiquine on liver stages was evaluated indirectly by the appearance of parasitaemia in the blood. The Clopper-Pearson CI (nominal 95%) was used to express the protection rate. The secondary outcomes were safety and tolerability, assessed in those who had received DVI and were administered one dose of the study intervention. The trial was prospectively registered on ClinicalTrials.gov (NCT04250363). FINDINGS: Between Feb 17, 2020 and April 29, 2021, 39 healthy participants were enrolled (early liver-stage: 30 mg [n=3], 60 mg [n=6], 80 mg [n=6], 100 mg [n=3], 200 mg [n=3], pooled placebo [n=6]; late liver-stage: 60 mg [n=3], 100 mg [n=3], 200 mg [n=3], pooled placebo [n=3]). A dose-dependent causal chemoprophylactic effect was observed, with four (67%) of six participants in the 60 mg, five (83%) of six participants in the 80 mg, and all three participants in the 100 and 200 mg cabamiquine dose groups protected from parasitaemia up to study day 28, whereas all participants in the pooled placebo and 30 mg cabamiquine dose group developed parasitaemia. A single, oral dose of 100 mg cabamiquine or higher provided 100% protection against parasitaemia when administered during early or late liver-stage malaria. The median time to parasitaemia in those with early liver-stage malaria was prolonged to 15, 22, and 24 days for the 30, 60, and 80 mg dose of cabamiquine, respectively, compared with 10 days for the pooled placebo. All participants with positive parasitaemia showed documented blood-stage parasite growth, apart from one participant in the pooled placebo group and one participant in the 30 mg cabamiquine group. Most participants did not exhibit any malaria symptoms in both the early and late liver-stage groups, and those reported were mild in severity. A positive dose-exposure-efficacy relationship was established across exposure metrics. The median maximum concentration time was 1-6 h, with a secondary peak observed between 6 h and 12 h in all cabamiquine dose groups (early liver-stage). All cabamiquine doses were safe and well tolerated. Overall, 26 (96%) of 27 participants in the early liver-stage group and ten (83·3%) of 12 participants in the late liver-stage group reported at least one treatment-emergent adverse event (TEAE) with cabamiquine or placebo. Most TEAEs were of mild severity, transient, and resolved without sequelae. The most frequently reported cabamiquine-related TEAE was headache. No dose-related trends were observed in the incidence, severity, or causality of TEAEs. INTERPRETATION: The results from this study show that cabamiquine has a dose-dependent causal chemoprophylactic activity. Together with previously demonstrated activity against the blood stages combined with a half-life of more than 150 h, these results indicate that cabamiquine could be developed as a single-dose monthly regimen for malaria prevention. FUNDING: The healthcare business of Merck KGaA, Darmstadt, Germany.


Assuntos
Antimaláricos , Malária Falciparum , Adulto , Humanos , Plasmodium falciparum , Países Baixos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia , Voluntários Saudáveis , Método Duplo-Cego
9.
PLoS Negl Trop Dis ; 15(6): e0007370, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34106922

RESUMO

BACKGROUND: Praziquantel (PZQ) is currently the only recommended drug for infection and disease caused by the schistosome species that infects humans; however, the current tablet formulation is not suitable for pre-school age children mainly due to its bitterness and the large tablet size. We assessed the palatability of two new orally disintegrating tablet (ODT) formulations of PZQ. METHODOLOGY: This randomized, single-blind, crossover, swill-and-spit palatability study (NCT02315352) was carried out at a single school in Tanzania in children aged 6-11 years old, with or without schistosomiasis infection as this was not part of the assessment. Children were stratified according to age group (6-8 years or 9-11 years) and gender, then randomized to receive each formulation in a pre-specified sequence. Over 2 days, the children assessed the palatability of Levo-Praziquantel (L-PZQ) ODT 150 mg and Racemate Praziquantel (Rac-PZQ) ODT 150 mg disintegrated in the mouth without water on the first day, and L-PZQ and Rac-PZQ dispersed in water and the currently available PZQ 600 mg formulation (PZQ-Cesol) crushed and dispersed in water on the second day. The palatability of each formulation was rated using a 100 mm visual analogue scale (VAS) incorporating a 5-point hedonic scale, immediately after spitting out the test product (VASt = 0 primary outcome) and after 2-5 minutes (VASt = 2-5). PRINCIPAL FINDINGS: In total, 48 children took part in the assessment. Overall, there was no reported difference in the VASt = 0 between the two ODT formulations (p = 0.106) without water. Higher VASt = 0 and VASt = 2-5 scores were reported for L-PZQ ODT compared with Rac-PZQ ODT in older children (p = 0.046 and p = 0.026, respectively). The VASt = 0 and VASt = 2-5 were higher for both ODT formulations compared with the standard formulation (p<0.001 for both time points). No serious adverse events were reported. CONCLUSIONS/SIGNIFICANCE: The new paediatric-friendly formulations dispersed in water were both found to be more palatable than the existing standard formulation of PZQ. There may be gender and age effects on the assessment of palatability. Further research is needed for assessing efficacy and tolerability of the newly ODTs Praziquantel drug in younger children. TRIAL REGISTRATION: The trial was registered on ClinicalTrials.gov (NCT02315352) and in the Pan African Clinical Trials Registry (PACTR201412000959159).


Assuntos
Anti-Helmínticos/administração & dosagem , Praziquantel/administração & dosagem , Paladar , Administração Oral , Criança , Estudos Cross-Over , Formas de Dosagem , Feminino , Humanos , Masculino , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Comprimidos , Tanzânia/epidemiologia
10.
Lancet Infect Dis ; 21(12): 1713-1724, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715032

RESUMO

BACKGROUND: M5717 is the first plasmodium translation elongation factor 2 inhibitor to reach clinical development as an antimalarial. We aimed to characterise the safety, pharmacokinetics, and antimalarial activity of M5717 in healthy volunteers. METHODS: This first-in-human study was a two-part, single-centre clinical trial done in Brisbane, QLD, Australia. Part one was a double-blind, randomised, placebo-controlled, single ascending dose study in which participants were enrolled into one of nine dose cohorts (50, 100, 200, 400, 600, 1000, 1250, 1800, or 2100 mg) and randomly assigned (3:1) to M5717 or placebo. A sentinel dosing strategy was used for each dose cohort whereby two participants (one assigned to M5717 and one assigned to placebo) were initially randomised and dosed. Randomisation schedules were generated electronically by independent, unblinded statisticians. Part two was an open-label, non-randomised volunteer infection study using the Plasmodium falciparum induced blood-stage malaria model in which participants were enrolled into three dose cohorts. Healthy men and women of non-childbearing potential aged 18-55 years were eligible for inclusion; individuals in the volunteer infection study were required to be malaria naive. Safety and tolerability (primary outcome of the single ascending dose study and secondary outcome of the volunteer infection study) were assessed by frequency and severity of adverse events. The pharmacokinetic profile of M5717 was also characterised (primary outcome of the volunteer infection study and secondary outcome of the single ascending dose study). Parasite clearance kinetics (primary outcome of the volunteer infection study) were assessed by the parasite reduction ratio and the corresponding parasite clearance half-life; the incidence of recrudescence up to day 28 was determined (secondary outcome of the volunteer infection study). Recrudescent parasites were tested for genetic mutations (exploratory outcome). The trial is registered with ClinicalTrials.gov (NCT03261401). FINDINGS: Between Aug 28, 2017, and June 14, 2019, 221 individuals were assessed for eligibility, of whom 66 men were enrolled in the single ascending dose study (eight per cohort for 50-1800 mg cohorts, randomised three M5717 to one placebo, and two in the 2100 mg cohort, randomised one M5717 to one placebo) and 22 men were enrolled in the volunteer infection study (six in the 150 mg cohort and eight each in the 400 mg and 800 mg cohorts). No adverse event was serious; all M5717-related adverse events were mild or moderate in severity and transient, with increased frequency observed at doses above 1250 mg. In the single ascending dose study, treatment-related adverse events occurred in three of 17 individuals in the placebo group; no individual in the 50 mg, 100 mg, or 200 mg groups; one of six individuals in each of the 400 mg, 1000 mg, and 1250 mg groups; two of six individuals in the 600 mg group; and in all individuals in the 1800 mg and 2100 mg groups. In the volunteer infection study, M5717-related adverse events occurred in no participants in the 150 mg or 800 mg groups and in one of eight participants in the 400 mg group. Transient oral hypoesthesia (in three participants) and blurred vision (in four participants) were observed in the 1800 mg or 2100 mg groups and constituted an unknown risk; thus, further dosing was suspended after dosing of the two sentinel individuals in the 2100 mg cohort. Maximum blood concentrations occurred 1-7 h after dosing, and a long half-life was observed (146-193 h at doses ≥200 mg). Parasite clearance occurred in all participants and was biphasic, characterised by initial slow clearance lasting 35-55 h (half-life 231·1 h [95% CI 40·9 to not reached] for 150 mg, 60·4 h [38·6 to 138·6] for 400 mg, and 24·7 h [20·4 to 31·3] for 800 mg), followed by rapid clearance (half-life 3·5 h [3·1 to 4·0] for 150 mg, 3·9 h [3·3 to 4·8] for 400 mg, and 5·5 h [4·8 to 6·4] for 800 mg). Recrudescence occurred in three (50%) of six individuals dosed with 150 mg and two (25%) of eight individuals dosed with 400 mg. Genetic mutations associated with resistance were detected in four cases of parasite recrudescence (two individuals dosed with 150 mg and two dosed with 400 mg). INTERPRETATION: The safety, pharmacokinetics, and antimalarial activity of M5717 support its development as a component of a single-dose antimalarial combination therapy or for malaria prophylaxis. FUNDING: Wellcome Trust and the healthcare business of Merck KGaA, Darmstadt, Germany.


Assuntos
Antimaláricos/farmacologia , Malária Falciparum/tratamento farmacológico , Fator 2 de Elongação de Peptídeos/antagonistas & inibidores , Adulto , Antimaláricos/farmacocinética , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum , Adulto Jovem
11.
Clin Transl Sci ; 12(1): 66-76, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30536632

RESUMO

Orally dispersible tablet (ODT) formulations of levo praziquantel (L-PZQ) and racemic PZQ (rac-PZQ) are being developed to treat schistosomiasis in preschool-aged children. Two crossover studies (N = 32 and 36, respectively) assessed the relative bioavailability of these ODTs vs. Cysticide in adults. Bioavailability for L-PZQ of ODT rac-PZQ and Cysticide at 40 mg/kg was comparable (L-PZQ area under the concentration-time curve from zero to infinity (AUC0-∞ ) test/reference ratio (90% confidence interval (CI)): 96% (84-111%)), whereas relative bioavailability of ODT L-PZQ 20 mg/kg was ~40% that of Cysticide 40 mg/kg (test/reference: 40% (35-46%)). AUC0-∞ and peak plasma concentration (Cmax ) were highly variable in both studies. For both ODTs, L-PZQ AUC0-∞ showed greater than dose-proportional increase over the ranges tested and a significant food effect. Safety was comparable among formulations. The lower bioavailability of ODT L-PZQ, as well as the high variability and nondose-proportionality of pharmacokinetic (PK) parameters, highlighted the need for a dedicated pediatric dose-finding study for the selection of the most appropriate formulation and dose (L-PZQ ODT or rac-PZQ ODT).


Assuntos
Anti-Helmínticos/farmacocinética , Praziquantel/farmacocinética , Esquistossomose/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Fatores Etários , Anti-Helmínticos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Pré-Escolar , Estudos Cross-Over , Relação Dose-Resposta a Droga , Cálculos da Dosagem de Medicamento , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Praziquantel/administração & dosagem , Praziquantel/química , Estereoisomerismo , Comprimidos , Equivalência Terapêutica , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-29375477

RESUMO

This was a Phase I, open-label, randomized, two-period, two-sequence crossover study [ClinicalTrials.gov NCT02317809 (https://www.clinicaltrials.gov/ct2/show/NCT02317809); EudraCT 2014-003506-32] assessing the bioequivalence of the liquid and freeze-dried formulations of fixed-dose, fixed-ratio (2:1) combination recombinant human follicle-stimulating hormone plus recombinant human luteinizing hormone (r-hFSH/r-hLH). The safety and tolerability of the two formulations were also assessed. Healthy premenopausal women were randomized to one of two crossover dosing schedules. Subjects in Treatment Sequence 1 received a single subcutaneous dose (900/450 IU r-hFSH/r-hLH) of the liquid formulation of r-hFSH/r-hLH on Day 1 of Dose Period 1 and, after a washout period of at least 14 days, a single subcutaneous dose (900/450 IU r-hFSH/r-hLH) of the freeze-dried formulation of r-hFSH/r-hLH (reconstituted in water for injection prior to administration) on Day 1 of Dose Period 2. Subjects in Treatment Sequence 2 received the treatments in reverse order. The primary endpoints were AUC0-t (area under the serum concentration-time curve from time 0 to the time of the last quantifiable concentration) and Cmax (maximum serum concentration) for FSH and LH, both baseline corrected. A total of 34 subjects were randomized, and 22 subjects were included in the bioequivalence evaluation. Overall, the mean observed PK profiles and individual PK parameters were comparable for the liquid and freeze-dried formulations, although a median difference in the tmax (time to reach maximum observed concentration) of FSH of ~4.5 h was observed between the formulations. The calculated 90% confidence intervals of the mean liquid formulation/freeze-dried formulation ratios for Cmax and AUC0-t were within the bioequivalence range (80-125%) for both LH and FSH, confirming bioequivalence between the two formulations. The safety and tolerability profiles of the two formulations were similar. The liquid formulation can, therefore, be expected to provide the same efficacy as the freeze-dried formulation, with no differences in tolerability.

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