Exploration of in Vivo Efficacy of Artemether-Lumefantrine Against Uncomplicated Plasmodium Falciparum Malaria in Under Fives in Tabora Region, Tanzania.

Tanzania adopted artemether-lumefantrine (AL) as first-line drug for uncomplicated malaria in 2006. Recently, there was an anecdotal report on high malaria recurrence rate following AL treatment in in the (urban and peri-urban), western part of Tanzania. The current report is an exploratory study to carefully and systematically assess AL efficacy in the area. Between June and August 2011, a total of 1,126 patients were screened for malaria, 33 had malaria, of which 20 patients met inclusion criteria and were enrolled and treated with standard dose of AL as recommended in the WHO protocol. Treated patients were followed up for 28 days to assess treatment responses. Before treatment (Day 0) and post-treatment (Day 7) plasma lumefantrine levels were determined to assess prior AL use and ascertain parasites exposure to adequate plasma leveles of lumefantrine, respectively. The cure rate was 100%. All Day 0 plasma lumefantrine were below HPLC detectable level. The median Day 7 lumefantrine concentration was 404, (range, 189-894 ng/ml). Six out of 20 patients (30%) were gametocytaemic and all cleared gametocytes by Day 14. One patient showed an increase in gametocytes from four on Day 0 to 68, per 500 WBC on Day 2. Artemether lumefantrine is highly efficacious against uncomplicated Plasmodium falciparum malaria. The elevation of gametocytaemia despite AL treatment needs to be evaluated in a larger study

Adherence to Antiretroviral Therapy among HIV Infected Children Measured by Caretaker Report, Medication Return, and Drug Level in Dar Es Salaam, Tanzania.

Adherence to antiretroviral drugs in the treatment of paediatric HIV infection is complicated because of many factors including stigma and drug intake logistics. It is therefore important to identify children with non-adherence in order to intervene before they become at risk of developing treatment failure or drug resistance. The aim of this study was to determine the level of adherence to antiretroviral therapy (ART), measured by caretaker report, medication return and nevirapine plasma concentration. In addition, the association between level of adherence and patient's immune status was compared across the three methods of measuring adherence. This was a descriptive cross-sectional study involving HIV infected children aged 2-14 years, on nevirapine- based antiretroviral treatment for at least six months, attending care and treatment clinic in three municipal hospitals in Dar- Es- Salaam City. Eligible patients and their accompanying caretakers were consecutively enrolled after obtaining written informed consent. Structured questionnaires were administered to caretakers to assess patient's adherence by caretaker report and medication return whereas a single blood sample for CD4 cell count/percent and determination of nevirapine plasma concentration was taken from patients on the day of assessment. A total of 300 patients and accompanying caretakers were enrolled and the mean patient age (SD) was 8 (3) years. Caretakers' report and medication return showed good adherence (98% and 97%) respectively. However, the level of adherence assessed by nevirapine plasma concentration (85%) was significantly lower than caretaker report and medication return (p < 0.001). The agreement between nevirapine plasma concentration and medication return and between nevirapine plasma concentration and caretaker report was weak (k = 0. 131) (k = 0. 09) respectively. Nevirapine plasma concentration below 3 μg/ml was associated with immunosuppression (p = 0. 021) whereas medication return (>5% of prescribed doses) and caretaker reported missing more than one dose within 72 hours prior to interview were not associated with immunosuppression (p = 0. 474), (p = 0. 569) respectively. Lower adherence level observed using nevirapine plasma concentration and its association with immunological response supports the validity of the method and indicates that adherence data obtained from caretaker report and medication return may overestimate the true adherence in paediatric antiretroviral therapy

Comparison of Bioavailability Between the Most Available Generic Tablet Formulation Containing Artemether and Lumefantrine on the Tanzanian Market and the Innovator's Product.

Existence of anti-malarial generic drugs with low bioavailability marketed on sub-Saharan Africa has raised a concern on patients achieving therapeutic concentrations after intake of these products. This work compared bioavailability of one generic tablet formulation with innovator's product. Both were fixed dose combination tablet formulations containing artemether and lumefantrine.MethodologyThe study was conducted in Dar Es Salaam, Tanzania, in which a survey of the most abundant generic containing artemether-lumefantrine tablet formulation was carried out in retail pharmacies. The most widely available generic (Artefan(R), Ajanta Pharma Ltd, Maharashtra, India) was sampled for bioavailability comparison with Coartem(R) (Novartis Pharma, Basel, Switzerland) - the innovator's product. A randomized, two-treatment cross-over study was conducted in 18 healthy Tanzanian black male volunteers. Each volunteer received Artefan(R) (test) and Coartem(R) (as reference) formulation separated by 42 days of drug-free washout period. Serial blood samples were collected up to 168 hours after oral administration of a single dose of each treatment. Quantitation of lumefantrine plasma levels was done using HPLC with UV detection. Bioequivalence of the two products was assessed in accordance with the US Food and Drug Authority (FDA) guidelines. The most widely available generic in pharmacies was Artefan(R) from India. All eighteen enrolled volunteers completed the study and both test and reference tablet formulations were well tolerated. It was possible to quantify lumefantrine alone, therefore, the pharmacokinetic parameters reported herein are for lumefantrine. The geometric mean ratios for Cmax, AUC0-t and AUC0-[infinity] were 84% in all cases and within FDA recommended bioequivalence limits of 80% -- 125%, but the 90% confidence intervals were outside FDA recommended limits (CI 49--143%, 53 - 137%, 52 - 135% respectively). There were no statistical significant differences between the two formulations with regard to PK parameters (P > 0.05). Although the ratios of AUCs and Cmax were within the acceptable FDA range, bioequivalence between Artefan(R) and Coartem(R) tablet formulations was not demonstrated due to failure to comply with the FDA 90 % confidence interval criteria. Based on the observed total drug exposure (AUCs), Artefan(R) is likely to produce a similar therapeutic response as Coartem(R)