Mitochondrial Dysfunction and Electron Transport Chain Complex Defect in a Rat Model of Tenofovir Disoproxil Fumarate Nephrotoxicity

The long‐term use of tenofovir, a commonly used anti‐HIV drug, can result in renal damage. The mechanism of tenofovir disoproxil fumarate (TDF) nephrotoxicity is not clear, although it has been shown to target proximal tubular mitochondria. In the present study, the effects of chronic TDF treatment on the proximal tubular function, renal mitochondrial function, and the activities of the electron transport chain (ETC) complexes were studied in rats. Damage to proximal tubular mitochondria and proximal tubular dysfunction was observed. The impaired mitochondrial function such as the respiratory control ratio, 2‐(4,5‐dimethyl‐2‐thiazolyl)‐3,5‐diphenyl‐2H‐tetrazolium bromide (MTT) reduction, and mitochondrial swelling was observed. The activities of the electron chain complexes I, II, IV, and V were decreased by 46%, 20%, 26%, and 21%, respectively, in the TDF‐treated rat kidneys. It is suggested that TDF induced proximal tubular mitochondrial dysfunction and ETC defects may impair ATP production, resulting in proximal tubular damage and dysfunction.     

An Indirect Comparison of Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate and Abacavir/Lamivudine + Dolutegravir in Initial Therapy

ObjectivesThe objective of this analysis is to perform an indirect comparison of elvitegravir, cobicistat, emtricitabine and tenofovir DF (E/C/F/TDF) to abacavir/lamivudine and dolutegravir (ABC/3TC + DTG) by using 2 trials evaluating each of these regimens in comparison to efavirenz, emtricitabine and tenofovir DF (EFV/FTC/TDF).MethodsAn indirect comparison was performed by using a generalization of Bucher''s methodology to calculate risk differences. Two phase III clinical trials (GS-US-236-0102 and SINGLE—described above) were used.ResultsResults of the indirect comparison showed no statistically significant risk difference of the efficacy endpoint of achieving HIV RNA < 50 copies/mL between E/C/F/TDF and ABC/3TC + DTG for the ITT population at weeks 48, 96 and 144: respectively -3.7% (CI95% = [-10.8%; 3.4%]), -5.2% (CI95% = [-13.2%; 2.8%]) and -3.1% (CI_95% = [-12.0%; 5.7%]). There was no statistically significant differences in the risk difference for serious adverse events (5.7% (CI95% = [-2.2%; 12.3%])), drug related adverse event (2.7% (CI95% = [-7.0%;12.4%])), drug related serious adverse event (0.8% (CI95% = [-1.6%;3.2%])) and death (0.5% (CI95% = [-0.8%;1.8%])), respectively, between E/C/F/TDF and ABC/3TC + DTG. A significant difference was found for discontinuation due to adverse events with a higher rate for E/C/F/TDF (difference = 8.6% (CI95% = [3.3%; 13.9%])). There was also no statistically significant risk difference of the viral resistance of 1.2% (CI95% = [-1.2; 3.7]) between E/C/F/TDF and ABC/3TC + DTG at week 48, 1.7% at week 96 (CI95% = [-1.1; 4.5]) and 2.2% (CI95% = [-1.0; 5.4]) at week 144.     

MTN-001: Randomized Pharmacokinetic Cross-Over Study Comparing Tenofovir Vaginal Gel and Oral Tablets in Vaginal Tissue and Other Compartments

Background

Oral and vaginal preparations of tenofovir as pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection have demonstrated variable efficacy in men and women prompting assessment of variation in drug concentration as an explanation. Knowledge of tenofovir concentration and its active form, tenofovir diphosphate, at the putative vaginal and rectal site of action and its relationship to concentrations at multiple other anatomic locations may provide key information for both interpreting PrEP study outcomes and planning future PrEP drug development.

Objective

MTN-001 was designed to directly compare oral to vaginal steady-state tenofovir pharmacokinetics in blood, vaginal tissue, and vaginal and rectal fluid in a paired cross-over design.

Methods and Findings

We enrolled 144 HIV-uninfected women at 4 US and 3 African clinical research sites in an open label, 3-period crossover study of three different daily tenofovir regimens, each for 6 weeks (oral 300 mg tenofovir disoproxil fumarate, vaginal 1% tenofovir gel [40 mg], or both). Serum concentrations after vaginal dosing were 56-fold lower than after oral dosing (p<0.001). Vaginal tissue tenofovir diphosphate was quantifiable in ≥90% of women with vaginal dosing and only 19% of women with oral dosing. Vaginal tissue tenofovir diphosphate was ≥130-fold higher with vaginal compared to oral dosing (p<0.001). Rectal fluid tenofovir concentrations in vaginal dosing periods were higher than concentrations measured in the oral only dosing period (p<0.03).

Conclusions

Compared to oral dosing, vaginal dosing achieved much lower serum concentrations and much higher vaginal tissue concentrations. Even allowing for 100-fold concentration differences due to poor adherence or less frequent prescribed dosing, vaginal dosing of tenofovir should provide higher active site concentrations and theoretically greater PrEP efficacy than oral dosing; randomized topical dosing PrEP trials to the contrary indicates that factors beyond tenofovir’s antiviral effect substantially influence PrEP efficacy.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00592124","term_id":"NCT00592124"}}NCT00592124     

A Phase 1 Randomized,Open Label,Rectal Safety,Acceptability, Pharmacokinetic,and Pharmacodynamic Study of Three Formulations of Tenofovir 1% Gel (the CHARM-01 Study)

Objectives

The CHARM-01 study characterized the safety, acceptability, pharmacokinetics (PK), and pharmacodynamics (PD) of three tenofovir (TFV) gels for rectal application. The vaginal formulation (VF) gel was previously used in the CAPRISA 004 and VOICE vaginal microbicide Phase 2B trials and the RMP-02/MTN-006 Phase 1 rectal safety study. The reduced glycerin VF (RGVF) gel was used in the MTN-007 Phase 1 rectal microbicide trial and is currently being evaluated in the MTN-017 Phase 2 rectal microbicide trial. A third rectal specific formulation (RF) gel was also evaluated in the CHARM-01 study.

Methods

Participants received 4 mL of the three TFV gels in a blinded, crossover design: seven daily doses of RGVF, seven daily doses of RF, and six daily doses of placebo followed by one dose of VF, in a randomized sequence. Safety, acceptability, compartmental PK, and explant PD were monitored throughout the trial.

Results

All three gels were found to be safe and acceptable. RF and RGVF PK were not significantly different. Median mucosal mononuclear cell (MMC) TFV-DP trended toward higher values for RF compared to RGVF (1136 and 320 fmol/10⁶ cells respectively). Use of each gel in vivo was associated with significant inhibition of ex vivo colorectal tissue HIV infection. There was also a significant negative correlation between the tissue levels of TFV, tissue TFV-DP, MMC TFV-DP, rectal fluid TFV, and explant HIV-1 infection.

Conclusions

All three formulations were found to be safe and acceptable. However, the safety profile of the VF gel was only based on exposure to one dose whereas participants received seven doses of the RGVF and RF gels. There was a trend towards higher tissue MMC levels of TFV-DP associated with use of the RF gel. Use of all gels was associated with significant inhibition of ex vivo tissue HIV infection.

Trial Registration

ClinicalTrials.gov NCT01575405     

A Phase 1 Randomized,Double Blind,Placebo Controlled Rectal Safety and Acceptability Study of Tenofovir 1% Gel (MTN-007)

Objective

Rectal microbicides are needed to reduce the risk of HIV acquisition associated with unprotected receptive anal intercourse. The MTN-007 study was designed to assess the safety (general and mucosal), adherence, and acceptability of a new reduced glycerin formulation of tenofovir 1% gel.

Methods

Participants were randomized 1∶1:1∶1 to receive the reduced glycerin formulation of tenofovir 1% gel, a hydroxyethyl cellulose placebo gel, a 2% nonoxynol-9 gel, or no treatment. Each gel was administered as a single dose followed by 7 daily doses. Mucosal safety evaluation included histology, fecal calprotectin, epithelial sloughing, cytokine expression (mRNA and protein), microarrays, flow cytometry of mucosal T cell phenotype, and rectal microflora. Acceptability and adherence were determined by computer-administered questionnaires and interactive telephone response, respectively.

Results

Sixty-five participants (45 men and 20 women) were recruited into the study. There were no significant differences between the numbers of ≥ Grade 2 adverse events across the arms of the study. Likelihood of future product use (acceptability) was 87% (reduced glycerin formulation of tenofovir 1% gel), 93% (hydroxyethyl cellulose placebo gel), and 63% (nonoxynol-9 gel). Fecal calprotectin, rectal microflora, and epithelial sloughing did not differ by treatment arms during the study. Suggestive evidence of differences was seen in histology, mucosal gene expression, protein expression, and T cell phenotype. These changes were mostly confined to comparisons between the nonoxynol-9 gel and other study arms.

Conclusions

The reduced glycerin formulation of tenofovir 1% gel was safe and well tolerated rectally and should be advanced to Phase 2 development.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01232803","term_id":"NCT01232803"}}NCT01232803.     

Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study

Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting via the oral route. From a clinical point of view, data suggest MFS-LNCs as a potential single dose oral nanomedicine for enhanced therapy of schistosomiasis mansoni and possibly other diseases.     

Comparison of Two Routines for Long-Term Oral Hygiene Treatment with Chlorhexidine Gel in Geriatric Patients1

The aims of the present study were to register the effect of toothbrushing with chlorhexidine gel for 51 weeks and compare the effect of two hygiene regimens, one with continuous use of chlorhexidine gel for toothbrushing twice a day and the other in which ordinary toothpaste was substituted for chlorhexidine 1 week every third week. The total number of participating patients was 152 institutionalized elderly, mean age 76.2 years, Gingival Index according to Löe-Silness and Plaque Index according to Bay-Ainamo were registered 12 times during the study. The long-term effect of Toothbrushing with chlorhexidine gel was equal for the two hygiene regimens. The incidence of side effects was surprising small. Moderate discolouration of teeth occurred with equal distribution in both groups.     

Single Oral Dose Pharmacokinetics of Decursin and Decursinol Angelate in Healthy Adult Men and Women

The ethanol extract of Angelica gigas Nakai (AGN) root has promising anti-cancer and other bioactivities in rodent models. It is currently believed that the pyranocoumarin isomers decursin (D) and decursinol angelate (DA) contribute to these activities. We and others have documented that D and DA were rapidly converted to decursinol (DOH) in rodents. However, our in vitro metabolism studies suggested that D and DA might be metabolized differently in humans. To test this hypothesis and address a key question for human translatability of animal model studies of D and DA or AGN extract, we conducted a single oral dose human pharmacokinetic study of D and DA delivered through an AGN-based dietary supplement Cogni.Q (purchased from Quality of Life Labs, Purchase, NY) in twenty healthy subjects, i.e., 10 men and 10 women, each consuming 119 mg D and 77 mg DA from 4 vegicaps. Analyses of plasma samples using UHPLC-MS/MS showed mean time to peak concentration (T_max) of 2.1, 2.4 and 3.3 h and mean peak concentration (C_max) of 5.3, 48.1 and 2,480 nmol/L for D, DA and DOH, respectively. The terminal elimination half-life (t_1/2) for D and DA was similar (17.4 and 19.3 h) and each was much longer than that of DOH (7.4 h). The mean area under the curve (AUC_0-48h) for D, DA and DOH was estimated as 37, 335 and 27,579 h∙nmol/L, respectively. Gender-wise, men absorbed the parent compounds faster and took shorter time to reach DOH peak concentration. The human data supported an extensive conversion of D and DA to DOH, even though they metabolized DA slightly slower than rodents. Therefore, the data generated in rodent models concerning anti-cancer efficacy, safety, tissue distribution and pharmacodynamic biomarkers will likely be relevant for human translation.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT02114957","term_id":"NCT02114957"}}NCT02114957     

Alteration of the Systemic and Microcirculation by a Single Oral Dose of Flavan-3-Ols

Several systematic reviews have reported that flow mediated dilatation (FMD) was significantly increased in subjects after ingestion of chocolate that contains flavan-3-ols; however, the mechanisms responsible for this effect are not clear. In this study, we evaluated the effects of a single oral dose of flavan-3-ols on the systemic circulation and microcirculation in the cremaster muscle using intravital video microscopy in vivo. The cremaster muscle in rats was spread over a plastic chamber and a gastric tube was placed into the stomach. Blood flow in the cremasteric artery was determined using a laser Doppler flowmeter, while blood pressure and heart rate were measured by the tail-cuff method. Red blood cell velocity in arterioles and blood flow in the artery were significantly increased 5 min after the administration of 10 mg/kg flavan-3-ols compared with distilled water treatment. The number of capillaries recruited in the cremaster muscle was also significantly increased 15 min after treatment. Microscopic observation confirmed that increased shear stress on endothelial cells was maintained during the measurement period. The mean arterial blood pressure and heart rate were also significantly elevated soon after administration and returned to baseline before the end of the observation period. Plasma nitrate and nitrite levels, and NO phosphorylation of aortic tissue were significantly increased at 60 min after administration of flavan-3-ols. According to these results, a single oral dose of flavan-3-ols elevates blood pressure and flow transiently, and these effects induce NO production through increased shear stress on endothelial cells.     

五灵胶囊联合富马酸丙酚替诺福韦片对慢性乙型肝炎患者氧化应激、CD4+CD25+调节性T细胞和血清MMP-1、MMP-2、TIMP-1的影响

摘要 目的：探讨五灵胶囊联合富马酸丙酚替诺福韦片对慢性乙型肝炎（CHB）患者氧化应激、CD4⁺CD25⁺调节性T细胞和血清基质金属蛋白酶-1（MMP-1）、基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶组织抑制因子-1（TIMP-1）的影响。方法：纳入苏州大学附属传染病医院2021年6月~2022年12月期间收治的CHB患者122例,采用随机数字表法分为对照组（n=61,富马酸丙酚替诺福韦片）和研究组（n=61,五灵胶囊联合富马酸丙酚替诺福韦片）。对比两组疗效、氧化应激指标、CD4⁺CD25⁺调节性T细胞、肝功能指标[总胆红素（TBIL）、谷丙转氨酶（ALT）、谷氨酰转肽酶（GGT）]、血清MMP-1、MMP-2、TIMP-1水平和不良反应发生情况。结果：研究组的临床总有效率高于对照组（P<0.05）。两组治疗后丙二醛（MDA）下降,且研究组低于对照组同时间点;超氧化物歧化酶（SOD）升高,且研究组高于对照组同时间点（P<0.05）。两组治疗后CD4⁺CD25⁺调节性T细胞下降,且研究组低于对照组同时间点（P<0.05）。两组治疗后MMP-1、MMP-2、TIMP-1下降,且研究组低于对照组同时间点（P<0.05）。两组治疗后TBIL、ALT、GGT下降,且研究组低于对照组同时间点（P<0.05）。两组不良反应总发生率组间对比未见差异（P>0.05）。结论：五灵胶囊联合富马酸丙酚替诺福韦片治疗CHB患者,可有效减轻机体氧化应激,调节CD4⁺CD25⁺调节性T细胞和血清MMP-1、MMP-2、TIMP-1水平。     

A Randomised Trial Evaluating the Safety and Immunogenicity of the Novel Single Oral Dose Typhoid Vaccine M01ZH09 in Healthy Vietnamese Children

Background

The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC ⁻ ssaV ⁻) ZH9 with two independently attenuating deletions. Studies in healthy adults demonstrated immunogenicity and an acceptable safety profile.

Objectives

We conducted a randomised placebo controlled, single-blind trial to evaluate the safety and immunogenicity of M01ZH09 in healthy Vietnamese children aged 5 to 14 years.

Methods

Subjects were randomly assigned to receive either a nominal dose of 5×10⁹ CFU of M01ZH09 or placebo and were followed up for 28 days. The primary safety outcome was the proportion of subjects with any adverse event attributed to M01ZH09. The primary immunogenicity endpoint was the proportion of subjects who showed a positive immune response to M01ZH09 in the Salmonella Typhi lipopolysaccharide (LPS) specific serum IgA and IgG ELISA.

Principal Findings

One hundred and fifty-one children were enrolled, 101 subjects received M01ZH09 and 50 subjects received placebo. An intention to treat analysis was conducted. There were no serious adverse events and no bacteraemias. In the M01ZH09 group, 26 (26%; 95% CI, 18–5%) of 101 subjects experienced adverse events compared to 11 (22%; 95% CI, 12–36%) of 50 subjects in the placebo group (odds ratio (OR) [95%CI]  = 1.23 [0.550–2.747]; p = 0.691). Faecal shedding of S. Typhi (Ty2 aroC ⁻ ssaV ⁻) ZH9 was detected in 51 (51%; 95% CI, 41–61%) of 100 M01ZH09 subjects. No shedding was detected beyond day 3. A positive immune response, defined as 70% increase (1.7 fold change) in LPS specific serum IgG (day 14 or 28) and/or 50% increase (1.5 fold change) in LPS specific serum IgA (day 7 or 14) from baseline was detected in 98 (97%; 95% CI, 92–99%) of 101 M01ZH09 recipients and 8 (16%; 95% CI, 7–29%) of 50 placebo recipients. Twenty-eight (100%; 95% CI, 88–100%) of 28 vaccine recipients who were evaluated in the LPS specific IgA ELISPOT assay showed a positive response compared to none of the 14 placebo recipients tested.

Conclusions

This was the first phase II trial of a novel oral candidate typhoid vaccine in children in an endemic country. M01ZH09 had an appropriate safety profile and was immunogenic in children.

Trial Registration

Controlled-trials.comISRCTN91111837     

Amiloride Effects on Taste Quality: Comparison of Single and Multiple Response Category Procedures

Although there is compelling evidence that amiloride reducesthe intensity of Na⁺ and Li⁺ salts in humans, its effects onsaltiness are conflicting. Many salts elicit not only a saltytaste but also one or more side tastes (sweetness, sournessor bitterness). Some studies have shown a suppression of saltinessby amiloride; others show no effect on saltiness but a significantreduction in sourness. In the experiments demonstrating a reductionof saltiness, subjects estimated only saltiness; in those showingan amiloride effect on sourness and not saltiness, subjectsestimated all qualities on each trial. The present study examinesthe role of the psychophysical method in these conflicting results.We have investigated the effects of amiloride on taste qualityby modifying only the instructions to the subjects, keepingall other variables constant. One group of subjects (intensity-only)gave magnitude estimates of the overall intensity of a LiCIconcentration series. A second group (salty-only) was instructedto estimate the saltiness of the stimuli, and a third group(sour-only) estimated their sourness. Finally, a fourth group(profile) rated all of the taste qualities on each stimuluspresentation, using a modified taste profile method. The ratingsof all groups were made comparable by the use of 0.1 mM quinine-HCIas a modulus. When subjects used only one response category,amiloride reduced their estimates (of intensity, saltiness orsourness), but if subjects attended to all four qualities, amiloridespecifically reduced the sourness of LJCI and had no significanteffect on its saltiness. Comparison of the saltiness estimatesof the salty-only group to the sum of the salty and sour estimatesof the profile group demonstrated that subjects combined thesesensations when presented with only one response alternative.To reveal the effect of amiloride on a specific quality of asalt, the psychophysical method must allow subjects to attendto all qualities on each trial. These data and previous resultssuggest that apical Na⁺ channels on the taste receptor cellmembrane mediate the sourness but not the saltiness of Na⁺ andLi⁺ salts. Chem. Senses 22: 267–275, 1997.     

Single and Multiple Dose Pharmacokinetics,Pharmacodynamics and Safety of the Novel Lipoprotein-Associated Phospholipase A2 Enzyme Inhibitor Darapladib in Healthy Chinese Subjects: An Open Label Phase-1 Clinical Trial

Background and Objectives

Darapladib is a lipoprotein-associated phospholipase A₂ (Lp-PLA₂) inhibitor. This study evaluated the pharmacokinetics, pharmacodynamics and safety of darapladib in healthy Chinese subjects.

Methods

Twenty-four subjects received darapladib 160 mg orally, approximately 1 hour after a standard breakfast, as a single dose and once daily for 28 days. Non-compartmental methods were used to determine the single and multiple dose pharmacokinetics of darapladib and its metabolite SB-553253. Repeat dose Lp-PLA₂ activity and safety were evaluated.

Results

Systemic exposure (AUC_(0-T), Cmax geometric mean (CVb%)) of darapladib was higher after multiple-dosing (519 ng.h/mL (33.3%), 34.4 ng/mL (49.9%)) compared to single-dose administration (153 ng.h/mL (69.0%), 17.9 ng/mL (55.2%). The steady-state accumulation ratio was less than unity (Rs = 0.80), indicating time-dependent pharmacokinetics of darapladib. Darapladib steady-state was reached by Day 14 of once daily dosing. Systemic exposure to SB-553253 was lower than darapladib with median (SB-553253: darapladib) ratios for AUC_(0-τ) of 0.0786 for single dose and 0.0532 for multiple dose administration. On Day 28, pre-dose and maximum inhibition of Lp-PLA₂ activity was approximately 70% and 75% relative to the baseline value, respectively and was dependent of darapladib concentration. The most common adverse events (≥ 21% subjects) were abnormal faeces, abnormal urine odour, diarrhoea and nasopharyngitis.

Conclusion

Darapladib 160 mg single and repeat doses were profiled in healthy Chinese subjects. Single dose systemic exposure to darapladib in healthy Chinese subjects was consistent with that observed previously in Western subjects whereas steady-state systemic exposure was approximately 65% higher in Chinese than Western subjects. The Lp-PLA₂ activity and adverse event profile were similar in healthy Chinese and previous reports in Western subjects. Ethnic-specific dose adjustment of darapladib is not considered necessary for the Chinese population.

Trial Registration

ClinicalTrials.gov NCT02000804     

A Study of Chlorhexidine Gel Treatment in an Oral Hygiene Program for Elderly Patients in Long Term Care1

An investigation was made to measure the effectiveness of one of the newer agents used in promotion of oral hygiene, i.e., Chlorhexidine gel. The study was designed with elderly people in long term care.     

Single Versus Double Dose Praziquantel Comparison on Efficacy and Schistosoma mansoni Re-Infection in Preschool-Age Children in Uganda: A Randomized Controlled Trial

Background

Schistosoma mansoni infection is proven to be a major health problem of preschool-age children in sub-Saharan Africa, yet this age category is not part of the schistosomiasis control program. The objective of this study was to compare the impact of single and double dose praziquantel (PZQ) treatment on cure rates (CRs), egg reduction rates (ERRs) and re-infection rates 8 months later, in children aged 1-5 years living along Lake Victoria, Uganda.

Methodology/Principal Findings

Infected children (n= 1017) were randomized to receive either a single or double dose of PZQ. Initially all children were treated with a single standard oral dose 40 mg/kg body weight of PZQ. Two weeks later a second dose was administered to children in the double dose treatment arm. Side effects were monitored at 30 minutes to 24 hours after each treatment. Efficacy in terms of CRs and ERRs for the two treatments was assessed and compared 1 month after the second treatment. Re-infection with S. mansoni was assessed in the same children 8 months following the second treatment. CRs were non-significantly higher in children treated with two 40 mg/kg PZQ doses (85.5%; 290/339) compared to a single dose (83.2%; 297/357). ERRs were significantly higher in the double dose with 99.3 (95%CI: 99.2-99.5) compared with 98.9 (95%CI: 98.7-99.1) using a single dose, (P = 0.01). Side effects occurred more frequently during the first round of drug administration and were mild and short-lived; these included vomiting, abdominal pain and bloody diarrhea. Overall re-infection rate 8 months post treatment was 44.5%.

Conclusions

PZQ is efficacious and relatively safe to use in preschool-age children but there is still an unmet need to improve its formulation to suit small children. Two PZQ doses lead to significant reduction in egg excretion compared to a single dose. Re-infection rates with S. mansoni 8 months post treatment is the same among children irrespective of the treatment regimen.     

Fractioned Dose Regimen of Sunitinib for Patients with Gastrointestinal Stromal Tumor: A Pharmacokinetic and Treatment Efficacy Study

AIM: Sunitinib has shown benefit in patients with imatinib (IM)–resistant gastrointestinal stromal tumor (GIST). However, its advantages are somewhat diminished because of associated toxicities. Herein, we clarify the efficacy and safety of fractioned dose regimen of sunitinib by a pharmacokinetic and efficacy study. MATERIALS AND METHODS: Between 2001 and March 2013, a total of 214 patients with metastatic GIST was treated at Chang Gung Memorial Hospital. Among them, 55 (11.6%) patients who received sunitinib were investigated. One group of patients was administered with standard dose of once-daily sunitinib (standard dose group) and the other group was administered with standard total daily dose of sunitinib in fractioned doses (fractioned dose group). RESULTS: Thirty-two male and 23 female patients with a median age of 55 years received sunitinib. The median duration of sunitinib administration was 9.2 months. The clinical benefit was 65.2%. The mean peak blood level of sunitinib in patients with fractioned doses was significantly lower than that in those with once-daily dose (83.4 vs 50.1 ng/ml, P = .01). The rates of adverse effects of hand-foot syndrome, mucositis, and yellow skin were significantly decreased by fractioned doses of sunitinib. However, the progression-free and overall survival did not differ between patients with different treatment regimens. CONCLUSION: The fractioned dose regimen of sunitinib appears to be a safe and effective treatment for patients with IM-resistant/intolerant GISTs. Significantly decreased toxicity of this regimen could be explained by significantly lower peak sunitinib blood level. However, the treatment efficacy is not reduced by this regimen.     

Genetic and Non-Genetic Determinants of Raltegravir Penetration into Cerebrospinal Fluid: A Single Arm Pharmacokinetic Study

Background

Antiretroviral drugs vary in their central nervous system penetration, with better penetration possibly conferring neurocognitive benefit during human immunodeficiency virus (HIV) therapy. The efflux transporter gene ABCB1 is expressed in the blood-brain barrier, and an ABCB1 variant (3435C→T) has been reported to affect ABCB1 expression. The integrase inhibitor raltegravir is a substrate for ABCB1. We examined whether ABCB1 3435C→T affects raltegravir disposition into cerebrospinal fluid (CSF), and explored associations with polymorphisms in other membrane transporter genes expressed in the blood-brain barrier.

Methods

Forty healthy, HIV-negative adults of European descent (20 homozygous for ABCB1 3435 C/C, 20 homozygous for 3435 T/T, each group divided equally between males and females) were given raltegravir 400 mg twice daily for 7 days. With the final dose, plasma was collected for pharmacokinetic analysis at 9 timepoints over 12 hours, and CSF collected 4 hours post dose.

Results

The 4-hour CSF concentration correlated more strongly with 2-hour (r²=0.76, P=1.12x10^-11) than 4-hour (r²=0.47, P=6.89x10^-6) single timepoint plasma concentration, and correlated strongly with partial plasma area-under-the-curve values (AUC_0-4h r²=0.86, P=5.15x10^-16). There was no significant association between ABCB1 3435C→T and ratios of CSF-to-plasma AUC or concentration (p>0.05 for each comparison). In exploratory analyses, CSF-to-plasma ratios were not associated with 276 polymorphisms across 16 membrane transporter genes.

Conclusions

Among HIV-negative adults, CSF raltegravir concentrations do not differ by ABCB1 3435C→T genotype but strongly correlate with plasma exposure.

Trial Registration

ClinicalTrials.gov NCT00729924 http://clinicaltrials.gov/show/NCT00729924     

A Novel,Single Algorithm Approach to Predict Acenocoumarol Dose Based on CYP2C9 and VKORC1 Allele Variants

The identification of CYP2C9 and VKORC1 genes has strongly stimulated the research on pharmacogenetics of coumarins in the last decade. We assessed the combined influence of CYP2C9 *2 and *3, and VKORC1 c.-1639G>A, 497C>G, and 1173C>T variants, on acenocoumarol dosage using a novel algorithm approach, in 193 outpatients who had achieved stable anticoagulation. We constructed an “acenocoumarol-dose genotype score” (AGS, maximum score = 100) based on the number of alleles associated with higher acenocoumarol dosage carried by each subject for each polymorphism. The mean AGS was higher in the high-dose (>28mg/week) compared with the low-dose (<7mg/week) group (mean(SEM) of 84.1±3.4 vs. 62.2±4.8, P = 0.008). An AGS>70 was associated with an increased odds ratio (OR) of requiring high acenocoumarol dosage (OR: 3.347; 95%CI: 1.112–10.075; P = 0.032). In summary, although more research is necessary in other patient cohorts, and this algorithm should be replicated in an independent sample, our data suggest that the AGS algorithm could be used to help discriminating patients requiring high acenocoumarol doses to achieve stable anti-coagulation.