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Andrew Kitua,
Peter Folb,
Marian Warsame,
Fred Binka,
Abul Faiz,
Isabela Ribeiro,
Tom Peto,
John Gyapong,
Emran Bin Yunus,
Ridwan Rahman,
Frank Baiden,
Christine Clerk,
Zakayo Mrango,
Charles Makasi,
Omari Kimbute,
Amir Hossain,
Rasheda Samad, Melba Gomes
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Andrew Kitua,
Peter Folb,
Marian Warsame,
Fred Binka,
Abul Faiz,
Isabela Ribeiro,
Tom Peto,
John Gyapong,
Emran Bin Yunus,
Ridwan Rahman,
Frank Baiden,
Christine Clerk,
Zakayo Mrango,
Charles Makasi,
Omari Kimbute,
Amir Hossain,
Rasheda Samad, Melba Gomes
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ABSTRACT: Placebo-controlled trials are controversial when individuals might be denied existing beneficial medical interventions. In the case of malaria, most patients die in rural villages without healthcare facilities. An artesunate suppository that can be given by minimally skilled persons might be of value when patients suddenly become too ill for oral treatment but are several hours from a facility that can give injectable treatment for severe disease. In such situations, by default, no treatment is (or can be) given until the patient reaches a facility, making the placebo control design clinically relevant; alternative bioequivalence designs at the facility would misrepresent reality and risk incorrect conclusions. We describe the ethical issues underpinning a placebo-controlled trial in severe malaria. To protect patients and minimise risk, all patients were referred immediately to hospital so that each had a higher chance of prompt treatment through participation. There was no difference between artesunate and placebo in patients who reached clinic rapidly; among those who could not, a single artesunate suppository significantly reduced death or permanent disability, a finding of direct and indirect benefit to patients in participating villages and elsewhere.
Journal of medical ethics 02/2010; 36(2):116-20. · 1.21 Impact Factor
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ABSTRACT: Abstract
Background
Malaria kills. A single rectal dose of artesunate before referral can reduce mortality and prevent permanent disability. However, the success of this intervention depends on caretakers' adherence to referral advice for follow-up care. This paper explores the dilemma facing caretakers when they are in the process of deciding whether or not to transit their child to a health facility after pre-referral treatment with rectal artesunate.
Methods
Four focus group discussions were held in each of three purposively selected villages in Mtwara rural district of Tanzania. Data were analysed manually using latent qualitative content analysis.
Results
The theme "Caretakers dilemma in deciding whether or not to adhere with referral advice after pre-referral treatment with rectal artesunate" depicts the challenge they face. Caretakers' understanding of the rationale for going to hospital after treatment - when and why they should adhere - influenced adherence. Caretakers, whose children did not improve, usually adhered to referral advice. If a child had noticeably improved with pre-referral treatment however, caretakers weighed whether they should proceed to the facility, balancing the child's improved condition against other competing priorities, difficulties in reaching the health facilities, and the perceived quality of care at the health facility. Some misinterpretation were found regarding the urgency and rationale for adherence among some caretakers of children who improved which were attributed to be possibly due to their prior understanding.
Conclusion
Some caretakers did not adhere when their children improved and some who adhered did so without understanding why they should proceed to the facility. Successful implementation of the rectal artesunate strategy depends upon effective communication regarding referral to clinic.
Malaria Journal. 01/2010;
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Christine Manyando,
Rhoda Mkandawire,
Lwipa Puma,
Moses Sinkala,
Evans Mpabalwani,
Eric Njunju, Melba Gomes,
Isabela Ribeiro,
Verena Walter,
Mailis Virtanen,
Raymond Schlienger,
Marc Cousin,
Miriam Chipimo,
Frank M Sullivan
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ABSTRACT: Safety data regarding exposure to artemisinin-based combination therapy in pregnancy are limited. This prospective cohort study conducted in Zambia evaluated the safety of artemether-lumefantrine (AL) in pregnant women with malaria.
Pregnant women attending antenatal clinics were assigned to groups based on the drug used to treat their most recent malaria episode (AL vs. sulphadoxine-pyrimethamine, SP). Safety was assessed using standard and pregnancy-specific parameters. Post-delivery follow-up was six weeks for mothers and 12 months for live births. Primary outcome was perinatal mortality (stillbirth or neonatal death within seven days after birth).
Data from 1,001 pregnant women (AL n = 495; SP n = 506) and 933 newborns (AL n = 466; SP n = 467) showed: perinatal mortality (AL 4.2%; SP 5.0%), comprised of early neonatal mortality (each group 2.3%), stillbirths (AL 1.9%; SP 2.7%); preterm deliveries (AL 14.1%; SP 17.4% of foetuses); and gestational age-adjusted low birth weight (AL 9.0%; SP 7.7%). Infant birth defect incidence was 1.8% AL and 1.6% SP, excluding umbilical hernia. Abortions prior to antenatal care could not be determined: abortion occurred in 4.5% of women treated with AL during their first trimester; none were reported in the 133 women exposed to SP and/or quinine during their first trimester. Overall development (including neurological assessment) was similar in both groups.
These data suggest that exposure to AL in pregnancy, including first trimester, is not associated with particular safety risks in terms of perinatal mortality, malformations, or developmental impairment. However, more data are required on AL use during the first trimester.
Malaria Journal 01/2010; 9:249. · 3.19 Impact Factor
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ABSTRACT: WHO recommends artemisinin suppository formulations as pre-referral treatment for children who are unable to take oral medication and cannot rapidly reach a facility for parenteral treatment. We investigated factors influencing caretakers' adherence to referral advice following pre-referral treatment of their children with rectal artesunate suppositories.
The study was nested within an intervention study that involved pre-referral treatment of all children who came to a community dispenser for treatment because they were unable to take oral medications because of repeated vomiting, lethargy, convulsions or altered consciousness. All patients who did not comply with referral advice were stratified by actions taken post-referral: taking their children to a drug shop, a traditional healer, or not seeking further treatment, and added to a random selection of patients who complied with referral advice. Caretakers of the children were interviewed about their socio-economic status (SES), knowledge about malaria, referral advice given and actions they took following pre-referral treatment. Interview data for 587 caretakers were matched with symptoms of the children, the time of treatment, arrival at a health facility or other actions taken post-pre-referral treatment.
The majority (93.5%) of caretakers reported being given referral advice by the community drug dispenser. The odds of adherence with this advice were three times greater for children with altered consciousness and/or convulsions than for children with other symptoms [odds ratio (OR) 3.47, 95% confidence interval (CI) 2.32-5.17, P < 0.001]. When questioned, caretakers who remembered when (OR 2.19, 95% CI 1.48-3.23, P < 0.001) and why (OR 1.77, 95% CI 1.07-2.95, P = 0.026) they were advised to proceed to health facility - were more likely to follow referral advice. Cost did not influence adherence except within a catchment area of facilities that charged for services. In these areas, costs deterred adherence by four to five times for those who had previously paid for laboratory services (OR = 0.25, 95% CI: 0.09-0.67, P = 0.006) or consultation (OR 0.20, 95% CI: 0.06-0.61, P = 0.005) compared with those who had not.
When given referral advice, caretakers of patients with life-threatening symptoms adhere to referral advice more readily than other caretakers. Health service charges deter adherence.
Tropical Medicine & International Health 06/2009; 14(7):775-83. · 2.80 Impact Factor
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ABSTRACT: Rectal administration of artemisinin derivatives has potential for early treatment for severe malaria in remote settings where injectable antimalarial therapy may not be feasible. Preparations available include artesunate, artemisinin, artemether and dihydroartemisinin. However each may have different pharmacokinetic properties and more information is needed to determine optimal dose and comparative efficacy with each another and with conventional parenteral treatments for severe malaria.
Individual patient data from 1167 patients in 15 clinical trials of rectal artemisinin derivative therapy (artesunate, artemisinin and artemether) were pooled in order to compare the rapidity of clearance of Plasmodium falciparum parasitaemia and the incidence of reported adverse events with each treatment. Data from patients who received comparator treatment (parenteral artemisinin derivative or quinine) were also included. Primary endpoints included percentage reductions in parasitaemia at 12 and 24 hours. A parasite reduction of >90% at 24 hours was defined as parasitological success.
Artemisinin and artesunate treatment cleared parasites more rapidly than parenteral quinine during the first 24 hours of treatment. A single higher dose of rectal artesunate treatment was five times more likely to achieve >90% parasite reductions at 24 hours than were multiple lower doses of rectal artesunate, or a single lower dose administration of rectal artemether.
Artemisinin and artesunate suppositories rapidly eliminate parasites and appear to be safe. There are less data on artemether and dihydroartemisinin suppositories. The more rapid parasite clearance of single high-dose regimens suggests that achieving immediate high drug concentrations may be the optimal strategy.
BMC Infectious Diseases 02/2008; 8:39. · 3.12 Impact Factor
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ABSTRACT: To test whether strict implementation of a standardised protocol for the management of malaria and provision of a financial incentive for health workers reduced mortality.
Randomised controlled intervention trial.
Paediatric ward at the national hospital in Guinea-Bissau. All children admitted to hospital with severe malaria received free drug kits.
951 children aged 3 months to 5 years admitted to hospital with a diagnosis of malaria randomised to normal or intervention wards.
Before the start of the study, all personnel were trained in the use of the standardised guidelines for the management of malaria, including strict follow-up procedures. Nurses and doctors were randomised to work on intervention or control wards. Personnel in the intervention ward received a small financial incentive ($50 (25 pounds sterling; 35 euros)/month for nurses and $160 for doctors) and their compliance with standard case management was closely monitored.
In-hospital mortality and cumulative mortality within 4 weeks of hospital admission.
In-hospital mortality was 5% for the intervention group and 10% in the control group (risk ratio 0.48, 95% confidence interval 0.29 to 0.79). The effect may have been stronger in patients with positive malaria slides (0.36, 0.16 to 0.80). Cumulative mortality 4 weeks after discharge was also lower in the intervention group (0.61, 0.40 to 0.95).
Supervising healthcare workers to adhere to a standardised treatment protocol was associated with greatly reduced in-hospital mortality. Financial incentives may be important for the dedication and compliance of staff members.
Clinical Trials NCT00465777 [ClinicalTrials.gov].
BMJ (Clinical research ed.). 11/2007; 335(7625):862.
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ABSTRACT: Preparatory to a community trial investigating how best to deliver rectal artesunate as pre-referral treatment for severe malaria; local understanding, perceptions of signs/symptoms of severe malaria and treatment-seeking patterns for and barriers to seeking biomedical treatment were investigated.
19 key informant interviews, 12 in-depth interviews and 14 focus group discussions targeting care-givers, opinion leaders, and formal and informal health care providers were conducted. Monthly fever episodes and danger signs or symptoms associated with severe malaria among under-fives were recorded. Respondents recognized convulsions, altered consciousness and coma, and were aware of their risks if not treated. But, these symptoms were perceived to be caused by supernatural forces, and traditional healers were identified as primary care providers. With some delay, mothers eventually visited a health facility when convulsions were part of the illness, despite pressures against this. Although vomiting and failure to eat/suck/drink were associated with malaria, they were not considered as indicators of danger signs unless combined with another more severe symptom. Study communities were familiar with rectal application of medicines.
Communities' recognition and awareness of major symptoms of severe malaria could encourage action, but perceptions of their causes and poor discrimination of other danger signs - vomiting and failure to feed - might impede early treatment. An effective health education targeting parents/guardians, decision-makers/advisors, and formal and informal care providers might be a prerequisite for successful introduction of rectal artemisinins as an emergency treatment. Role of traditional healers in delivering such medication to the community should be explored.
PLoS ONE 02/2007; 2(1):e149. · 4.09 Impact Factor
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ABSTRACT: This paper reviews recent trends in the production, supply and price of the active ingredients as well as finished ACT products. Production and cost data provided in this paper are based on an ongoing project (Artepal). Stability data are derived from a development project on rectal artesunate.
The artemisinin raw material and its derivatives appear to be very stable compared to the finished products. Supply of artemisinin changed in May 2004 when the Global Fund shifted financial support to qualified countries from chloroquine or sulphadoxine-pyrimethamine to an ACT for treatment of malaria. First, there was a sudden shortage of the starting material, and short term scarcity led to a steep rise in API price: it increased dramatically in 2004, from $350 per kg to more than $1000. Second, there was a parallel increase in the number of companies extracting artemisinin from 10 to 80 between 2003 and 2005 in China, and from 3 to 20 in Vietnam. Commercial cultivation began also in East Africa and Madagascar.A steady and predictable demand for the crop can eliminate such wide fluctuations and indirectly contribute to price stability of the herb, the API and ACT. With appropriate mechanisms to reduce those fluctuations, the cost of artemisinin might decrease sustainably to US$ 250-300 per kg.
Today the global health community is facing the risk of another cyclical swing with lower demand feeding into reduced planting of A. annua and, thereafter, a new shortage of the raw material and higher API prices. International donors, the largest purchasers for ACTs could better coordinate their activities, in order to guarantee purchase of ACTs and consequently of API with manufacturers. In parallel, the base of quality producers of APIs and finished ACT products needs to be broadened.While the ACT programme is still in its early stages, the consequences of another wave of artemisinin and ACT shortages would permanently discredit it and impede any progress in rolling malaria back.
Malaria Journal 02/2007; 6:125. · 3.19 Impact Factor
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Monica Longo,
Sara Zanoncelli,
Paola Della Torre,
Mariagrazia Riflettuto,
Francesco Cocco,
Manuela Pesenti,
Annamaria Giusti,
Paolo Colombo,
Marco Brughera,
Guy Mazué,
Visweswaran Navaratman, Melba Gomes,
Piero Olliaro
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ABSTRACT: Artemisinin derivatives are clinically effective and safe antimalarials, but are not recommended during the first trimester of pregnancy because of the resorptions and abnormalities seen in animal reproduction studies. Understanding how, when and what toxicity occurs is crucial to any assessment of clinical relevance. Previously, DHA has been shown in the rat whole embryo culture (WEC) to primarily affect primitive red blood cells (RBCs) causing subsequent tissue damage and dysmorphogenesis. To verify the primary target of DHA in vivo and to detect consequences induced by early damage on embryo development, pregnant female rats were orally treated on gestation days (GD) 9.5 and 10.5 with 7.5 or 15 mg/kg/day DHA and caesarean sectioned on GD11.5, 12.5, 13.5, 15 and 20. A parallel in vitro WEC study evaluated the role of oxidative damage and examined blood islands and primitive RBCs. In accordance with the WEC results, primitive RBCs from yolk sac hematopoiesis were the target of DHA in vivo. The resulting anemia led to cell damage, which depending on its degree, was either diffuse or focal. Embryonic response to acute anemia varied from complete recovery to malformation and death, depending on the extent of cell death. Malformations occurred only in litters with embryonic deaths. DHA induced low glutathione levels in RBCs, indicating that oxidative stress may be involved in artemisinin toxicity; effects were extremely rapid, with altered RBCs seen as early as GD10. In establishing the relevance of these findings to humans, one should consider differences in the development of rodents and humans. While yolk sac hematopoiesis occurs similarly in the two species, early placentation and extent of exposure differ. In particular, early hematopoiesis takes only 7 days in rats (during which RBCs expand in a clonal fashion) compared with 6 weeks in humans; thus the susceptible period in relation to the duration of exposure to an artemisinin-based treatment may be substantially different.
Reproductive Toxicology 12/2006; 22(4):797-810. · 3.23 Impact Factor
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Julie A Simpson,
Tsiri Agbenyega,
Karen I Barnes,
Gianni Di Perri,
Peter Folb, Melba Gomes,
Sanjeev Krishna,
Srivicha Krudsood,
Sornchai Looareesuwan,
Sharif Mansor, [......],
Francois Nosten,
Piero Olliaro,
Lorrin Pang,
Isabela Ribeiro,
Madalitso Tembo,
Michele van Vugt,
Steve Ward,
Kris Weerasuriya,
Kyaw Win,
Nicholas J White
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ABSTRACT: Intra-rectal artesunate has been developed as a potentially life-saving treatment of severe malaria in rural village settings where administration of parenteral antimalarial drugs is not possible. We studied the population pharmacokinetics of intra-rectal artesunate and the relationship with parasitological responses in patients with moderately severe falciparum malaria.
Adults and children in Africa and Southeast Asia with moderately severe malaria were recruited in two Phase II studies (12 adults from Southeast Asia and 11 children from Africa) with intensive sampling protocols, and three Phase III studies (44 children from Southeast Asia, and 86 children and 26 adults from Africa) with sparse sampling. All patients received 10 mg/kg artesunate as a single intra-rectal dose of suppositories. Venous blood samples were taken during a period of 24 h following dosing. Plasma artesunate and dihydroartemisinin (DHA, the main biologically active metabolite) concentrations were measured by high-performance liquid chromatography with electrochemical detection. The pharmacokinetic properties of DHA were determined using nonlinear mixed-effects modelling. Artesunate is rapidly hydrolysed in vivo to DHA, and this contributes the majority of antimalarial activity. For DHA, a one-compartment model assuming complete conversion from artesunate and first-order appearance and elimination kinetics gave the best fit to the data. The mean population estimate of apparent clearance (CL/F) was 2.64 (l/kg/h) with 66% inter-individual variability. The apparent volume of distribution (V/F) was 2.75 (l/kg) with 96% inter-individual variability. The estimated DHA population mean elimination half-life was 43 min. Gender was associated with increased mean CL/F by 1.14 (95% CI: 0.36-1.92) (l/kg/h) for a male compared with a female, and weight was positively associated with V/F. Larger V/Fs were observed for the patients requiring early rescue treatment compared with the remainder, independent of any confounders. No associations between the parasitological responses and the posterior individual estimates of V/F, CL/F, and AUC0-6h were observed.
The pharmacokinetic properties of DHA were affected only by gender and body weight. Patients with the lowest area under the DHA concentration curve did not have slower parasite clearance, suggesting that rectal artesunate is well absorbed in most patients with moderately severe malaria. However, a number of modelling assumptions were required due to the large intra- and inter-individual variability of the DHA concentrations.
PLoS Medicine 12/2006; 3(11):e444. · 16.27 Impact Factor
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ABSTRACT: Artemisinin derivatives are not currently recommended for use during the first trimester of pregnancy because they cause embryo death and some abnormalities in early pregnancy in animals. We studied the effects of dihydroartemisinin (DHA) in rat whole embryo cultures (WEC). DHA was added to the culture medium for the entire 48-h culture, 1.5 h at the beginning or at the end of the culture at 0.01-2 microg/mL. DHA affected primarily red blood cells during yolk sac hematopoiesis. Higher concentrations and longer exposure inhibited angiogenesis. Tissue damage (cell deaths) and effects on embryo morphology (neural tube, branchial arches, somites and caudal region defects) were attributed to these events. The viability of severely affected embryos beyond the 48-h assay is uncertain. These results help explain findings from animal data and provide evidence that the yolk sac is highly susceptible to artemisinin compounds. Extrapolating results to pregnant women exposed in the first trimester remains difficult. Pharmacovigilance and further studies of the mechanism of damage are needed.
Reproductive Toxicology 02/2006; 21(1):83-93. · 3.23 Impact Factor
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ABSTRACT: Over recent years, tuberculosis (TB) and disease caused by human immunodeficiency virus (HIV) have merged in a synergistic pandemic. The number of new cases of TB is stabilizing and declining, except in countries with a high prevalence of HIV infection. In these countries, where HIV is driving an increase in the TB burden, the capacity of the current tools and strategies to reduce the burden has been exceeded. This paper summarizes the current status of TB management and describes recent thinking and strategy adjustments required for the control of TB in settings of high HIV prevalence. We review the information on anti-TB drugs that is available in the public domain and highlight the need for continued and concerted efforts (including financial, human and infrastructural investments) for the development of new strategies and anti-TB agents.
Bulletin of the World Health Organisation 12/2005; 83(11):857-65. · 4.64 Impact Factor
