Efficacy of artemether-lumefantrine therapy for the treatment of uncomplicated Plasmodium falciparum malaria in Southwestern Ethiopia

Therapeutic efficacy and safety of artemether-lumefantrine combination therapy for the treatment of uncomplicated Plasmodium falciparum malaria at Teda Health Centre, Northwest Ethiopia, 2022/23

BACKGROUND

The emergence of Plasmodium falciparum drug resistance against artemisinin-based combination therapy has threatened malaria control efforts. Since malaria control and elimination plans are dependent on these drugs, they must remain efficacious. However, resistance to these drugs was detected in low-transmission settings and is predicted to emerge in high-transmission settings, including in unspecified areas of Ethiopia. Therefore, this study aimed to assess the therapeutic efficacy and safety of artemether-lumefantrine for the treatment of uncomplicated P. falciparum malaria.

METHODS

A single-arm prospective observational study was conducted at Teda Health Centre, Northwest Ethiopia, by following the 2009 World Health Organization efficacy study guidelines from September 2022 to February 2023. Patients with uncomplicated falciparum malaria were conveniently selected and treated with a standard dose of artemether-lumefantrine, along with a single low dose of primaquine. Then clinical and parasitological responses and haemoglobin levels were assessed during the 28-day scheduled follow-up. Blood films were examined and asexual parasites were quantified; axillary temperature was measured; and drug adverse events were assessed throughout the follow-up. Finally, the drug efficacy (adequate clinical and parasitological response) was determined by Kaplan-Meier and per-protocol analyses. The data were analysed using the WHO Excel spreadsheet and SPSS version 25 software.

RESULTS

The success rates of PCR uncorrected and corrected Kaplan-Meier analysis on day 28 were 95.8% (95% CI 87.5-98.6) and 97.3% (95% CI 89.4-99.3), respectively. The per-protocol PCR uncorrected and corrected adequate clinical and parasitological responses were 95.5% (95% CI 87.5-99.1) and 97% (95% CI 89.5-99.6), respectively. On day-3, 97% of study participants were free of asexual parasitaemia, and all of them were fever-free on day-2. All of the gametocyte-positive patients at baseline were found to be negative for gametocytes on day-2. Moreover, the baseline mean hemoglobin of 13.10 g/dl increased slightly on day-14 to 13.27 g/dl but significantly on day-28 to 13.69 g/dl in a paired sample t test. All adverse events reported were mild.

CONCLUSION

Artemether-lumefantrine continued to be an efficacious and safe drug for the treatment of uncomplicated Plasmodium falciparum malaria at the Teda Health Centre.

TRIAL REGISTRATION

unique ID# PACTR202309773069812 at https://pactr.samrc.ac.za on September 1, 2023.

Biology and epidemiology of Plasmodium falciparum and Plasmodium vivax gametocyte carriage: Implication for malaria control and elimination

Malaria is among the leading public health problems worldwide. Female anopheles mosquito orchestrates the transmission of malaria by taking gametocytes and introducing sporozoite while taking blood meals. Interrupting transmission is the major strategy for malaria elimination. The gametocyte stage is essential for the onward transmission of malaria. Thus, understanding its basic biology and epidemiology is key to malaria control and elimination. Therefore, the current review focuses on revealing the biology, prevalence, and determinants of gametocyte carriage as well as its implication on mitigation of malaria. It also illustrates the role of asymptomatic and sub-microscopic Plasmodium infections and G-6-PD deficiency in gametocyte carriage and hence malaria transmission. Gametocytogenesis is initiated at committed merozoites and gives rise to the development of gametocytes. The trigger for gametocytogenesis depends on the host, parasite, and intervention factors. Gametocytes pass through five developmental stages identifiable by molecular markers. A considerable number of malaria patients carry gametocytes at a sub-microscopic level, thereby serving as a potential infectious reservoir of transmission. Factors involving the human host, Plasmodium parasite, and intervention parameters play a critical role in gametocyte biology and prevalence. The contribution of asymptomatic and sub-microscopic infections to malaria transmission is unknown. The clear impact of G-6-PD deficiency on malaria control and elimination remains unclear. Lack of clarity on such issues might impede the success of interventions. Basic science and epidemiological studies should continue to overcome the challenges and cope with the ever-evolving parasite and guide interventions.

Safety and therapeutic efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria at Shecha health centre, Arba Minch, Ethiopia

BACKGROUND

In 2004, Ethiopia adopted artemether-lumefantrine (AL, Coartem^®) as first-line treatment for the management of uncomplicated Plasmodium falciparum malaria. Continuous monitoring of AL therapeutic efficacy is crucial in Ethiopia, as per the World Health Organization (WHO) recommendation. This study aimed to assess the therapeutic efficacy of AL in the treatment of uncomplicated P. falciparum infection.

METHODS

A 28 day onearm, prospective evaluation of the clinical and parasitological response to AL was conducted at Shecha Health Centre, Arba Minch town, Southern Ethiopia. Patients were treated with six-dose regimen of AL over three days and monitored for 28 days with clinical and laboratory assessments. Participant recruitment and outcome classification was done in accordance with the 2009 WHO methods for surveillance of anti-malarial drug efficacy guidelines.

RESULTS

A total of 88 study participants were enrolled and 69 of them completed the study with adequate clinical and parasitological response. Two late parasitological failures were observed, of which one was classified as a recrudescence by polymerase chain reaction (PCR). The PCRcorrected cure rate was 98.6% (95% CI 92.3-100). AL demonstrated a rapid parasite and fever clearance with no parasitaemia on day 2 and febrile cases on day 3. Gametocyte clearance was complete by day three. No serious adverse events were reported during the 28 days follow-up.

CONCLUSION

The study demonstrated high therapeutic efficacy and good safety profile of AL. This suggests the continuation of AL as the first-line drug for the treatment of uncomplicated P. falciparum malaria in Ethiopia. Periodic therapeutic efficacy studies and monitoring of markers of resistance are recommended for early detection of resistant parasites.

Therapeutic efficacy of artemether-lumefantrine, artesunate-amodiaquine and dihydroartemisinin-piperaquine in the treatment of uncomplicated Plasmodium falciparum malaria in Sub-Saharan Africa: A systematic review and meta-analysis

Background

Sub-Saharan Africa has the highest burden of malaria in the world. Artemisinin-based combination therapies (ACTs) have been the cornerstone in the efforts to reduce the global burden of malaria. In the effort to facilitate early detection of resistance for artemisinin derivatives and partner drugs, WHO recommends monitoring of ACT’s efficacy in the malaria endemic countries. The present systematic meta-analysis study summarises the evidence of therapeutic efficacy of the commonly used artemisinin-based combinations for the treatment of uncomplicated P. falciparum malaria in Sub-Saharan Africa after more than a decade since the introduction of the drugs.

Methods

Fifty two studies carried out from 2010 to 2020 on the efficacy of artemether-lumefantrine or dihydro-artemisinin piperaquine or artesunate amodiaquine in patients with uncomplicated P. falciparum malaria in Sub-Saharan Africa were searched for using the Google Scholar, Cochrane Central Register of controlled trials (CENTRAL), PubMed, Medline, LILACS, and EMBASE online data bases. Data was extracted by two independent reviewers. Random analysis effect was performed in STATA 13. Heterogeneity was established using I² statistics.

Results

Based on per protocol analysis, unadjusted cure rates in malaria infected patients treated with artemether-lumefantrine (ALU), artesunate-amodiaquine (ASAQ) and dihydroartemisinin-piperaquine (DHP) were 89%, 94% and 91% respectively. However, the cure rates after PCR correction were 98% for ALU, 99% for ASAQ and 99% for DHP.

Conclusion

The present meta-analysis reports the overall high malaria treatment success for artemether-lumefantrine, artesunate-amodiaquine and dihydroartemisinin-piperaquine above the WHO threshold value in Sub-Saharan Africa.

Efficacy and safety of artemether-lumefantrine for treatment of uncomplicated Plasmodium falciparum malaria in Ethiopia: a systematic review and meta-analysis

Background

Regular monitoring of anti-malarial drug efficacy is vital for establishing rational malaria treatment guidelines and ensuring adequate treatment outcomes. This study aimed to synthesize the available evidence on the efficacy of artemether–lumefantrine for the management of uncomplicated falciparum malaria in Ethiopia.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Relevant published studies were searched from the databases (PubMed, Google Scholar and Clinical trial registry) on published artemether–lumefantrine therapeutic efficacy studies conducted in Ethiopia from 2004 to 2020. The retrieved studies were assessed for quality using the modified Newcastle Ottawa Scale for observational studies and modified Jadad scale for interventional studies. Risk of bias was also assessed by using ROBINS-I tool. OpenMeta-Analyst software was used for the statistical analysis. The review protocol is registered in PROSPERO, number CRD42020201859.

Results

Fifteen studies (1523 participants) were included in the final analysis. The overall PCR-uncorrected pooled proportion of treatment success of artemether–lumefantrine therapy for uncomplicated falciparum malaria was 98.4% (95%CI 97.6–99.1). A random-effects model was used because of considerable heterogeneity [χ² = 20.48, df (14), P = 0.011 and I² = 31.65]. PCR-corrected pooled proportion of treatment success of artemether–lumefantrine therapy was 98.7% (95% CI 97.7–99.6). A random-effects model was used [χ² = 7.37, df(6), P = 0.287 and I² = 18.69]. Most studies included in the present review achieved a rapid reduction of fevers and parasitaemia between D0 and D3 of assessment. Adverse events were mostly mild and only two cases were reported as serious, but were not directly attributed to the drug.

Conclusion

The present meta-analysis suggests that artemether–lumefantrine therapy is efficacious and safe in treating uncomplicated falciparum malaria in Ethiopia. However, owing to the high risk of bias in the included studies, strong conclusions cannot be drawn. Further high-quality RCTs assessing anti-malarial efficacy and safety should be performed to demonstrates strong evidence of changes in parasite sensitivity to artemether–lumefantrine in Ethiopia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-03745-8.

Efficacy of artemisinin-lumefantrine for treatment of uncomplicated malaria after more than a decade of its use in Kenya

BACKGROUND

The resistance of Plasmodium falciparum to antimalarial drugs remains a major impairment in the treatment and eradication of malaria globally. Following the introduction of artemisinin-based combination therapy (ACT), there have been reports of delayed parasite clearance. In Kenya, artemether-lumefantrine (AL) is the recommended first-line treatment of uncomplicated malaria. This study sought to assess the efficacy of AL after a decade of use as the preferred method of managing malarial infections in Kenya. We assessed clinical and parasitological responses of children under 5 years between May and November 2015 in Chulaimbo sub-County, Kisumu, Kenya. Patients aged between 6 and 60 months with uncomplicated P. falciparum mono-infection, confirmed through microscopy, were enrolled in the study. The patients were admitted at the facility for 3 days, treated with a standard dose of AL, and then put under observation for the next 28 days for the assessment of clinical and parasitological responses. Of the 90 patients enrolled, 14 were lost to follow-up while 76 were followed through to the end of the study period. Seventy-five patients (98.7%) cleared the parasitaemia within a period of 48 h while one patient (1.3%) cleared on day 3. There was 100% adequate clinical and parasitological response. All the patients cleared the parasites on day 3 and there were no re-infections observed during the stated follow-up period. This study, therefore, concludes that AL is highly efficacious in clearing P. falciparum parasites in children aged ≥6 and ≤60 months. The study, however, underscores the need for continued monitoring of the drug to forestall both gradual ineffectiveness and possible resistance to the drug in all target users.

Therapeutic Efficacy of Artemether-Lumefantrine (Coartem®) for the Treatment of Uncomplicated Falciparum Malaria in Africa: A Systematic Review

Background

Africa still bears the largest burden of malaria as the majority of infections in the continent are caused by P. falciparum. Artemether-lumefantrine (AL, Coartem®) is the most widely used artemisinin-based combination therapy (ACT), for treating uncomplicated falciparum malaria globally. However, the development of resistance to antimalarial drugs is a major challenge for malaria control. In this review, the efficacy of AL for the treatment of uncomplicated falciparum malaria in Africa was evaluated.

Methods

Articles published between January 2015 and July 2019 were systematically searched using comprehensive search strings from PubMed/Medline, SCOPUS, and grey literature from Google Scholar. Interventional studies that followed patients for at least 28 days were included. Two reviewers independently assessed study eligibility, extracted data, and assessed risk of bias. All the included articles were measured to be good quality. While computing the efficacy of AL, polymerase chain reaction (PCR)–corrected cure rate (adequate clinical and parasitological response, ACPR) at day 28 was considered as the main endpoint. Meta-analysis was computed using STATA v 15 to calculate the pooled ACPR.

Results

In this review, 39 articles that reported the treatment outcome of 8,320 patients were included. After 28 days of follow-up, the pooled PCR uncorrected and corrected APCR was at 87% (95% CI: 85-90%) and 97.0% (95% CI: 96-98%), respectively. Moreover, the proportion of early treatment failure (ETF) was almost 0%, while most of the included articles reported <8% late treatment failures. The reinfection and recrudescence rate was less than 10% and 2.6%, respectively, within 28 days. We noted rapid fever and parasite clearance in which greater than 93% and 94% patients were parasite and fever free at day three following AL treatment.

Conclusions

This review discovered that despite more than a decade since its introduction, Coartem® remains effective and thus could continue to be the drug of choice for the treatment of uncomplicated falciparum malaria for all age groups in Africa. However, the risk of new emerging resistance for this combination warrants regular monitoring of its efficacy across the continent.

Therapeutic efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria in Chewaka District, Ethiopia

Background

The efficacy of artemether-lumefantrine (AL) for treatment of uncomplicated Plasmodium falciparum malaria in south-western Ethiopia is poorly documented. Regular monitoring of drug efficacy is an important tool for supporting national treatment policies and practice. This study investigated the therapeutic efficacy of AL for the treatment of P. falciparum malaria in Ethiopia.

Methods

The study was a one-arm, prospective, evaluation of the clinical and parasitological, responses to directly observed treatment with AL among participants 6 months and older with uncomplicated P. falciparum malaria. Real-time polymerase chain reaction (PCR) and nested PCR reaction methods were used to quantify and genotype P. falciparum. A modified protocol based on the World Health Organization 2009 recommendations for the surveillance of anti-malarial drug efficacy was used for the study with primary outcomes, clinical and parasitological cure rates at day-28. Secondary outcomes assessed included patterns of fever and parasite clearance. Cure rate on day-28 was assessed by intention to treat (ITT) and per protocol (PP) analysis. Parasite genotyping was also performed at baseline and at the time of recurrence of parasitaemia to differentiate between recrudescence and new infection.

Results

Of the 80 study participants enrolled, 75 completed the follow-up at day-28 with ACPR. For per protocol (PP) analysis, PCR-uncorrected and-corrected cure rate of AL among the study participants was 94.7% (95% CI 87.1–98.5) and 96% (95% CI 88.8–99.2), respectively. For intention to treat (ITT) analysis, the cure rate was 90% (95% CI 88.8–99.2). Based on Kaplan–Meier survival estimate, the cumulative incidence of failure rate of AL was 3.8% (95% CI 1.3–11.4). Only three participants 3.8% (95% CI 0.8–10.6) of the 80 enrolled participants were found to be positive on day-3. The day three-positive participants were followed up to day 28 and did not correspond to treatment failures observed during follow-up. Only 7.5% (6/80) of the participants were gametocyte-positive on enrollment and gametocytaemia was absent on day-2 following treatment with AL.

Conclusions

The therapeutic efficacy of AL is considerably high (above 90%). AL remained highly efficacious in the treatment of uncomplicated malaria in the study area resulted in rapid fever and parasite clearance as well as low gametocyte carriage rates despite the use of this combination for more than 15 years.

Usefulness of day 7 lumefantrine plasma concentration as a predictor of malaria treatment outcome in under-fives children treated with artemether-lumefantrine in Tanzania

Background

Day 7 plasma lumefantrine concentration is suggested as a predictor for malaria treatment outcomes and a cut-off of ≥ 200 ng/ml is associated with day 28 cure rate in the general population. However, day 7 lumefantrine plasma concentration can be affected by age, the extent of fever, baseline parasitaemia, and bodyweight. Therefore, this study assessed the usefulness of day 7 lumefantrine plasma concentration as a predictor of malaria treatment outcome in under-fives children treated with generic or innovator drug-containing artemether-lumefantrine (ALu) in Tanzania.

Methods

This study was nested in an equivalence prospective study that aimed at determining the effectiveness of a generic ALu (Artefan^®) in comparison with the innovator’s product (Coartem^®). Children with uncomplicated malaria aged 6–59 months were recruited and randomized to receive either generic or innovator’s product. Children were treated with ALu as per World Health Organization recommendations. The clinical and parasitological outcomes were assessed after 28 days of follow up. PCR was performed to distinguish recrudescence and re-infections among children with recurrent malaria. Analysis of day 7 lumefantrine plasma concentration was carried out using a high-performance liquid chromatographic method with UV detection.

Results

The PCR corrected cure rates were 98.7% for children treated with generic and 98.6% for those treated with the innovator product (p = 1.00). The geometric mean (± SD) of day 7 plasma lumefantrine concentration was 159.3 (± 2.4) ng/ml for the generic and 164 (± 2.5) ng/ml for the innovator groups, p = 0.87. Geometric mean (± SD) day 7 lumefantrine plasma concentration between cured and recurrent malaria was not statistically different in both treatment arms [158.5 (± 2.4) vs 100.0 (± 1.5) ng/ml, (p = 0.28) for generic arm and 158.5 (± 2.3) vs 251.2 (± 4.2) ng/ml, (p = 0.24) for innovator arm]. Nutritional status was found to be a determinant of recurrent malaria (adjusted hazardous ratio (95% confidence interval) = 3(1.1–8.2), p = 0.029.

Conclusion

Using the recommended cut-off point of ≥ 200 ng/ml, day 7 plasma lumefantrine concentration failed to predict malaria treatment outcome in children treated with ALu in Tanzania. Further studies are recommended to establish the day 7 plasma lumefantrine concentration cut-off point to predict malaria treatment outcome in children.

Comparison of malaria treatment outcome of generic and innovator's anti-malarial drugs containing artemether-lumefantrine combination in the management of uncomplicated malaria amongst Tanzanian children

Background

In 2006, artemether–lumefantrine (ALU), specifically Coartem^® (Novartis Pharma AG, Basel Switzerland), was approved as the first-line drug for treatment of uncomplicated malaria in Tanzania. Due to poor availability and affordability of the innovator’s product, the government of Tanzania in 2013 prequalified the use of generic anti-malarial drugs, whereby Artefan^® (Ajanta, Pharma Ltd, India) was the first to be approved.

Methods

This was an equivalence prospective study that aimed to determine the effectiveness of anti-malarial generic Artefan^® in comparison with innovator’s product Coartem^®. Patients aged 6 to 59 months with uncomplicated malaria were recruited and randomized to either receive Artefan^® or Coartem^® as a control. Participants were required to revisit clinic five times as follow up to monitor treatment outcome as per World Health Organization recommendations. On each visit, thick and thin blood smears, dried blood spot (DBS), haemoglobin concentrations and auxiliary temperature were performed and documented.

Results

Out of 230 recruited participants, 200 met inclusion criteria and were randomized equally to receive Artefan^® and Coartem^®. The overall PCR uncorrected cure rate were 80% for Artefan^® and 75% for Coartem^® (p = 0.44). Adequate clinical and parasitological response were 82.1% for Artefan^® and 74.7% for Coartem^®, and there was no early treatment failure (ETF) observed in both arms of treatment. Both drugs showed excellent early parasite clearance, whereby no participants had peripheral parasitaemia on day 3. Late clinical failures (LCF) were 3.6% for Artefan^® and 1.3% for Coartem^® (p = 0.31), and late parasitological failure (LPF) were 15.4% for Artefan^® and 22.7% for Coartem^® (p = 0.32). Mean haemoglobin (g/dl) concentrations observed on day 28 were higher compared to day 0 for both drugs, although not statistically significant. Only one (1.3%) participant on Artefan^® had temperature ≥ 37.5 °C on day 3.

Conclusion

The findings of this study indicate that both Artefan^® and Coartem^® are equivalent and effective in the management of uncomplicated malaria amongst children in the Coast part of Tanzania.

Detection of foci of residual malaria transmission through reactive case detection in Ethiopia

Background

Sub-microscopic and asymptomatic infections could be bottlenecks to malaria elimination efforts in Ethiopia. This study determined the prevalence of malaria, and individual and household-level factors associated with Plasmodium infections obtained following detection of index cases in health facilities in Jimma Zone.

Methods

Index malaria cases were passively detected and tracked in health facilities from June to November 2016. Moreover, family members of the index houses and neighbours located within approximately 200 m from the index houses were also screened for malaria.

Results

A total of 39 index cases initiated the reactive case detection of 726 individuals in 116 households. Overall, the prevalence of malaria using microscopy and PCR was 4.0% and 8.96%, respectively. Seventeen (43.6%) of the index cases were from Doyo Yaya kebele, where parasite prevalence was higher. The majority of the malaria cases (90.74%) were asymptomatic. Fever (AOR = 12.68, 95% CI 3.34–48.18) and history of malaria in the preceding 1 year (AOR = 3.62, 95% CI 1.77–7.38) were significant individual-level factors associated with detection of Plasmodium infection. Moreover, living in index house (AOR = 2.22, 95% CI 1.16–4.27), house with eave (AOR = 2.28, 95% CI 1.14–4.55), area of residence (AOR = 6.81, 95% CI 2.49–18.63) and family size (AOR = 3.35, 95% CI 1.53–7.33) were main household-level predictors for residual malaria transmission.

Conclusion

The number of index cases per kebele may enhance RACD efforts to detect additional malaria cases in low transmission settings. Asymptomatic and sub-microscopic infections were high in the study area, which need new or improved surveillance tools for malaria elimination efforts.

Efficacy of artesunate-amodiaquine in the treatment of falciparum uncomplicated malaria in Madagascar

Background

Since 2006, the artemisinin-based combination therapy (ACT) are recommended to treat uncomplicated malaria including non Plasmodium falciparum malaria in Madagascar. Artesunate–amodiaquine (ASAQ) and artemether–lumefantrine are the first- and second-line treatment in uncomplicated falciparum malaria, respectively. No clinical drug efficacy study has been published since 2009 to assess the efficacy of these two artemisinin-based combinations in Madagascar, although the incidence of malaria cases has increased from 2010 to 2016. In this context, new data about the efficacy of the drug combinations currently used to treat malaria are needed.

Methods

Therapeutic efficacy studies evaluating the efficacy of ASAQ were conducted in 2012, 2013 and 2016 among falciparum malaria-infected patients aged between 6 months and 56 years, in health centres in 6 sites representing different epidemiological patterns. The 2009 World Health Organization protocol for monitoring anti-malarial drug efficacy was followed.

Results

A total of 348 enrolled patients met the inclusion criteria including 108 patients in 2012 (n = 64 for Matanga, n = 44 for Ampasipotsy), 123 patients in 2013 (n = 63 for Ankazomborona, n = 60 for Anjoma Ramartina) and 117 patients in 2016 (n = 67 for Tsaratanana, n = 50 for Antanimbary). The overall cumulative PCR-corrected day 28 cure rate was 99.70% (95% IC 98.30–99.95). No significant difference in cure rates was observed overtime: 99.02% (95% IC 94.65–99.83) in 2012; 100% (95% IC 96.8–100) in 2013 and 100% (95% IC 96.65–100) in 2016.

Conclusion

The ASAQ combination remains highly effective for the treatment of uncomplicated falciparum malaria in Madagascar.

Therapeutic efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria in Ethiopia: a systematic review and meta-analysis

Background

As Ethiopia is one of the sub-Saharan countries with a great burden of malaria the effectiveness of first line anti-malarial drugs is the major concern. The aim of this study was to synthesize the available evidence on the efficacy of artemether-lumefantrine in the treatment of uncomplicated Plasmodium falciparum malaria in Ethiopia. This was done by performing a meta-analysis of recent studies conducted in the country on this topic.

Methods

Studies published between January 2010 and January 2017 that reported on the efficacy of artemether-lumefantrine in the treatment of P. falciparum malaria in Ethiopian patients were searched for using the PubMed and Google Scholar databases. Ten prospective single-arm cohort studies that followed patients for 28–42 days were included in this analysis. All of the included studies were deemed to be of high quality.

Results

Ten studies involving 1179 patients that were eligible for meta-analysis were identified. At recruitment, the average parasite count per patient was 1 2981/μl of blood. On the third day of treatment, 96.7% and 98.5% of the study subjects become fever-free and parasite-free, respectively. Based on the per protocol analysis, the cure rate after use of artemether-lumefantrine was 98.2% (polymerase chain reaction corrected) and 97.01% (polymerase chain reaction uncorrected) after 28 days of follow-up. The reinfection rate within 28 days was 1.1% and the recrudescence rate was 1.9%.

Conclusions

This review found that the cure rate for uncomplicated P. falciparum malaria using artemether-lumefantrine in Ethiopia is still high enough to recommend the drug as a first-line agent. There should be careful periodic monitoring of the efficacy of this drug, as treatment failure may occur due to resistance, sub-therapeutic levels that may occur due to non-adherence, or inadequate absorption.

Electronic supplementary material

The online version of this article (10.1186/s40249-017-0372-5) contains supplementary material, which is available to authorized users.

Anti-malarial treatment outcomes in Ethiopia: a systematic review and meta-analysis

BACKGROUND

Ethiopia is among countries with a high malaria burden. There are several studies that assessed the efficacy of anti-malarial agents in the country and this systematic review and meta-analysis was performed to obtain stronger evidence on treatment outcomes of malaria from the existing literature in Ethiopia.

METHODS

A systematic literature search using the preferred reporting items for systematic review and meta-analysis (PRISMA) statement was conducted on studies from Pubmed, Google Scholar, and ScienceDirect databases to identify published and unpublished literature. Comprehensive meta-analysis software was used to perform all meta-analyses. The Cochrane Q and the I 2 were used to evaluate heterogeneity of studies. Random effects model was used to combine studies showing heterogeneity of Cochrane Q p < 0.10 and I 2  > 50.

RESULTS

Twenty-one studies were included in the final analysis with a total number of 3123 study participants. Treatment outcomes were assessed clinically and parasitologically using World Health Organization guidelines. Adequate clinical and parasitological response was used to assess treatment success at the 28th day. Overall, a significant high treatment success of 92.9% (95% CI 89.1-96.6), p < 0.001, I 2  = 98.39% was noticed. However, treatment success was higher in falciparum malaria patients treated with artemether-lumefantrine than chloroquine for Plasmodium vivax patients [98.1% (97.0-99.2), p < 0.001, I 2  = 72.55 vs 94.7% (92.6-96.2), p < 0.001, I 2  = 53.62%]. Seven studies reported the adverse drug reactions to anti-malarial treatment; of 822 participants, 344 of them were exposed to adverse drug reactions with a pooled event rate of 39.8% (14.1-65.5), p = 0.002.

CONCLUSIONS

On the basis of this review, anti-malarial treatment success was high (92.9%) and standard regimens showed good efficacy against Plasmodium falciparum (98.1%) and P. vivax (94.7%) infections in Ethiopia, but associated with high rates of adverse drug reactions (ADRs). However, these ADRs were not serious enough to discontinue anti-malarial treatment. The results of this study suggest that the current anti-malarial medications are effective and safe; however, greater priority should be placed on the discovery of new anti-malarial drugs to achieve successful outcomes as resistance seems inevitable since cases of anti-malarial drug resistance have been reported from other areas of the world.

Therapeutic efficacy of artemether-lumefantrine against uncomplicated Plasmodium falciparum malaria in a high-transmission area in northwest Ethiopia

Malaria, particularly due to Plasmodium falciparum, remains a major public health threat in Ethiopia. Artemether-lumefantine (AL) has been the first-line antimalarial drug against uncomplicated P. falciparum malaria in the country since 2004. Regular monitoring of antimalarial drugs is recommended by the World Health Organization (WHO) to help early detection of drug resistant strains of the parasite and contain their rapid spread. The objective of this study was to assess the therapeutic efficacy of AL in a high-transmission setting in Ethiopia. The study site was Setit Humera, northwest Ethiopia. Single-arm prospective study of a 28-day follow-up was conducted from October 2014 to January 2015 according to the revised WHO 2009 drug efficacy study protocol. Study end-points were classified into primary end-point and secondary end-point. While the primary end-point was the day-28 adequate clinical and parasitological response the secondary end-points were clinical and parasitological evaluations (parasite, fever and gametocyte clearance rate, incidence of drug adverse events) and the relative increment in hemoglobin (Hb) level from baseline to day (D) 14 and D28. A total of 92 patients were enrolled and 79 had completed the 28-day follow-up period. The overall cure rate was 98.8% with 95% confidence interval of 0.915-0.998 without polymerase chain reaction correction. The parasite clearance rate was high with fast resolution of clinical symptoms; 100% of the study participants cleared parasitaemia and fever on D3. Gametocyte carriage was reduced from 7% on D0 to 1% on D3 and complete clearance was achieved on D14. Mean Hb concentration significantly increased on D28 compared to that on D14. There was no serious adverse event. AL was efficacious and safe in a high-transmission setting for treatment of uncomplicated falciparum malaria.

In vivo efficacy of artemether-lumefantrine against uncomplicated Plasmodium falciparum malaria in Dembia District, northwest Ethiopia

Background

Artemether–lumefantrine (AL) has been used as a first-line treatment for uncomplicated Plasmodium falciparum malaria in Ethiopia since 2004. Antimalarial drug resistance is one of the major obstacles for malaria control and curtails the lifespan of several drugs. Thus, continued monitoring of the efficacy of AL is of great public health importance in malaria endemic areas.

Objective

This study aimed to investigate the therapeutic efficacy and safety of AL for the treatment of uncomplicated P. falciparum malaria in the Dembia district, northwest Ethiopia.

Methods

A prospective study was conducted from April 2015 to February 2016 at Kola Diba Health Center (KHC) in the Dembia district to determine the therapeutic efficacy and safety of AL for the treatment of uncomplicated P. falciparum monoinfection. Patients were treated with the six-dose regimen of AL over 3 days and followed up for 28 days as per the World Health Organization protocol.

Results

Of the total 80 patients enrolled in the AL efficacy study, 75 patients completed the 28 days follow-up. None of the participants reported major adverse events. No early treatment failure or late clinical failure were observed during the study, but there were 6 (8.0%) late parasitological failures. The uncorrected per protocol cure rate of AL was 92.0 (95% CI: 85.7–98.3). Treatment with AL cleared parasitemia and fever in >95% of the patients by day 3.

Conclusion

This study showed that AL is well tolerated and remains efficacious for treatment of uncomplicated P. falciparum malaria in northwest Ethiopia. However, the observed late parasitological failures in this study are of a concern and warrant continued monitoring of drug efficacy as per the World Health Organization recommendations.

Therapeutic efficacy of artemether-lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria from three highly malarious states in India

Background

Anti-malarial drug resistance continues to be a leading threat to malaria control efforts and calls for continued monitoring of waning efficacy of artemisinin-based combination therapy (ACT). Artesunate + sulfadoxine/pyrimethamine (AS + SP) is used for the treatment of uncomplicated Plasmodium falciparum malaria in India. However, resistance against AS + SP is emerged in northeastern states. Therefore, artemether–lumefantrine (AL) is the recommended first line treatment for falciparum malaria in north eastern states. This study investigates the therapeutic efficacy and safety of AL for the treatment of uncomplicated falciparum malaria in three malaria-endemic states in India. The data generated through this study will benefit the immediate implementation of second-line ACT as and when required.

Methods

This was a one-arm prospective evaluation of clinical and parasitological responses for uncomplicated falciparum malaria using WHO protocol. Patients diagnosed with uncomplicated mono P. falciparum infection were administered six-dose regimen of AL over 3 days and subsequent follow-up was carried out up to 28 days. Molecular markers msp-1 and msp-2 were used to differentiate recrudescence and re-infection and K13 propeller gene was amplified and sequenced covering the codon 450–680.

Results

A total of 402 eligible patients were enrolled in the study from all four sites. Overall, adequate clinical and parasitological response (ACPR) was 98 % without PCR correction and 99 % with PCR correction. At three study sites, ACPR rates were 100 %, while at Bastar, cure rate was 92.5 % on day 28. No early treatment failure was found. The PCR-corrected endpoint finding confirmed that one late clinical failure (LCF) and two late parasitological failures (LPF) were recrudescences. The PCR corrected cure rate was 96.5 %. The mean fever clearance time was 27.2 h ± 8.2 (24–48 h) and the mean parasite clearance time was 30.1 h ± 11.0 (24–72 h). Additionally, no adverse event was recorded. Analysis of total 186 samples revealed a mutation in the k13 gene along with non-synonymous mutation at codon M579T in three (1.6 %) samples.

Conclusion

AL is an efficacious drug for the treatment of uncomplicated falciparum malaria. However, regular monitoring of AL is required in view of malaria elimination initiatives, which will be largely dependent on therapeutic interventions, regular surveillance and targeted vector control.

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-016-1555-4) contains supplementary material, which is available to authorized users.

Efficacy of Chloroquine for the Treatment of Vivax malaria in Northwest Ethiopia

Background

Resistance to anti-malarials is a major challenge for effective malaria control in sub-Saharan Africa. This triggered a need for routine monitoring of the efficacy of the antimalarial drugs every two years in all malaria endemic countries. Chloroquine remained the drug of choice for the treatment of vivax malaria in Ethiopia. Though, a strong scientific evidence of chloroquine resistance to P.vivax that could have brought change of treatment regimen is yet to be established in Ethiopia, continuous and regular monitoring of drug’s efficacy is critical for establishing rational anti-malarial drug policies. This study therefore, assessed the therapeutic efficacy of Chloroquine (CQ) for the treatment of Plasmodium vivax infections in Northwestern Ethiopia.

Methods

An observational, 28- day therapeutic clinical efficacy study was conducted from August to December, 2014, in Northwest Ethiopia. Patients confirmed to have monoinfection of vivax malaria, aged above 6 months were included. All subjects were treated with standard chloroquine dose of 25 mg/kg for three (3) days. Parasitological and clinical outcomes of treated patients were then evaluated on days 1, 2, 3, 7, 14, 21, and 28 during the entire 28-day follow-up period. A portable spectrophotometer (HemoCue Hb 301 System, Sweden) was used to estimate hemoglobin concentration.

Results

A total of 69 subjects had completed follow up. Some 57/69 (82.6%) had fever at enrolment and the rest 12 patients 48 hours before enrollment. Out of total, 65/69 (94.2%) and 66/69 (95.6%) of the study subjects were free of fever by day 1 and day 2 respectively but fever was cleared in all subjects by day 3. At base line the mean asexual parasitemia was 3540 parasites/μL of blood. Parasite carriage on day 3 was 3%. The overall cure rate (an adequate and clinical parasitological response) was very high (97%) [(95% CI = 93.1–99.4)]. The time to parasite, fever and gametocyte clearance as expressed in mean (SD) was 35 (3), 25 (4.6), 28 (3.2) hours respectively. Mean hemoglobin was significantly increased (P<0.001) from 12.2 (7–15) g/dl at day 0 to 13.3 (10–16) g/dl on day 28.

Conclusions

In view of our findings, CQ remains efficacious for the treatment of vivax malaria in the study area. However, there is a need to monitor CQR regularly using molecular and or biochemical tools for better evaluation of treatment outcomes.

Open-label trial on efficacy of artemether/lumefantrine against the uncomplicated Plasmodium falciparum malaria in Metema district, Northwestern Ethiopia

Purpose

Following the increased Plasmodium falciparum resistance to chloroquine and sulfadoxine/pyrimethamine, Ethiopia adopted artemether/lumefantrine (AL) as the first-line treatment for uncomplicated P. falciparum in 2004. According to the recommendation of the World Health Organization, this study was carried out for regular monitoring of the efficacy of AL in treating the uncomplicated P. falciparum malaria in Metema district, Gondar Zone, Northwest Ethiopia.

Patients and methods

This is a one-arm prospective 28-day in vivo therapeutic efficacy study among the uncomplicated P. falciparum malaria patients aged 6 months and older. The study was conducted from October 2014 to January 2015, based on the revised World Health Organization protocol of 2009 for surveillance of antimalarial drug therapeutic efficacy study. Standard six-dose regimen of AL was given twice daily for 3 days, and then the treatment outcomes were assessed on days 0, 1, 2, 3, 7, 14, 21, 28, and any other unscheduled day for emergency cases.

Results

There were 91 study subjects enrolled in this study, of whom 80 study subjects completed the full follow-up schedules and showed adequate clinical and parasitological responses on day 28, with no major adverse event. Per protocol analysis, the unadjusted cure rate of Coartem^® was 98.8% (95% confidence interval: 93.3%–100%) in the study area. Recurrence of one P. falciparum case was detected on day 28, with a late parasitological failure rate of 1.2%. No early treatment failure occurred. Complete parasite and fever clearance was observed on day 3. Gametocyte carriage was 4.4% at enrollment that cleared on day 21. Although the difference is statistically not significant, a slight increase in the level of mean hemoglobin from baseline to day 28 was observed.

Conclusion

The study showed high efficacy and tolerability of Coartem^® against uncomplicated P. falciparum malaria, suggesting the continuation as a first-line drug in the study district. However, regular monitoring of the therapeutic efficacy of the drug, possibly with plasma drug-level measurement, is critical among the mobile border population.

Therapeutic efficacy trial of artemisinin-based combination therapy for the treatment of uncomplicated malaria and investigation of mutations in k13 propeller domain in Togo, 2012-2013

BACKGROUND

Since 2005, the Togo National Malaria Control Programme has recommended two different formulations of artemisinin-based combination therapy (ACT), artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL), for the treatment of uncomplicated malaria. Regular efficacy monitoring of these two combinations is conducted every 2 or 3 years. This paper reports the latest efficacy assessment results and the investigation of mutations in the k13 propeller domain.

METHODS

The study was conducted in 2012-2013 on three sentinel sites of Togo (Lomé, Sokodé and Niamtougou). Children aged 6-59 months, who were symptomatically infected with Plasmodium falciparum, were treated with either AL (Coartem(®), Novartis Pharma, Switzerland) or ASAQ (Co-Arsucam(®), Sanofi Aventis, France). The WHO standard protocol for anti-malarial treatment evaluation was used. The primary end-point was 28-day adequate clinical and parasitological response (ACPR), corrected to exclude reinfection using polymerase-chain reaction (PCR) genotyping.

RESULTS

A total of 523 children were included in the study. PCR-corrected ACPR was 96.3-100 % for ASAQ and 97-100 % for AL across the three study sites. Adverse events were negligible: 0-4.8 % across all sites, for both artemisinin-based combinations. Upon investigation of mutations in the k13 propeller domain, only 9 (1.8 %) mutations were reported, three in each site. All mutant parasites were cleared before day 3. All day 3 positive patients were infected with k13 wild type parasites.

CONCLUSIONS

The efficacy of AL and ASAQ remains high in Togo, and both drugs are well tolerated. ASAQ and AL would be recommended for the treatment of uncomplicated malaria in Togo.

Combining long-lasting insecticidal nets and indoor residual spraying for malaria prevention in Ethiopia: study protocol for a cluster randomized controlled trial

BACKGROUND

Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the main malaria prevention interventions in Ethiopia. There is conflicting evidence that the combined application of both interventions is better than either LLINs or IRS used alone. This trial aims to investigate whether the combination of LLINs (PermaNet 2.0, Vestergaard Frandsen, Lausanne, Switzerland) with IRS using propoxur will enhance the protective benefits and cost-effectiveness of the interventions against malaria and its effect on mosquito behavior, as compared to each intervention alone.

METHODS/DESIGN

This 2 x 2 factorial cluster randomized controlled trial is being carried out in the Adami Tullu district in south-central Ethiopia for about 116 weeks from September 2014 to December 2016. The trial is based on four arms: LLINs + IRS, LLINs alone, IRS alone and control. Villages (or clusters) will be the unit of randomization. The sample size includes 44 clusters per arm, with each cluster comprised of approximately 35 households (about 175 people). Prior to intervention, all households in the LLINs + IRS and LLINs alone arms will be provided with LLINs free of charge. Households in the LLINs + IRS and IRS alone arms will be sprayed with carbamate propoxur once a year just before the main malaria transmission season throughout the investigation. The primary outcome of this trial will be a malaria incidence based on the results of the rapid diagnostic tests in patients with a fever or history of fever attending health posts by passive case detection. Community-based surveys will be conducted each year to assess anemia among children 5-59 months old. In addition, community-based malaria prevalence surveys will be conducted each year on a representative sample of households during the main transmission season. The cost-effectiveness of the interventions and entomological studies will be simultaneously conducted. Analysis will be based on an intention-to-treat principle.

DISCUSSION

This trial aims to provide evidence on the combined use of LLINs and IRS for malaria prevention by answering the following research questions: Can the combined use of LLINs and IRS significantly reduce the incidence of malaria compared with the use of either LLINs or IRS alone? And is the reduced incidence justifiable compared to the added costs? Will the combined use of LLINs and IRS reduce vector density, infection, longevity and the entomological inoculation rate? These data are crucial in order to maximize the impact of vector control interventions on the morbidity and mortality of malaria.

TRIAL REGISTRATION

PACTR201411000882128 (8 September 2014).

Quality of malaria diagnosis and molecular confirmation of Plasmodium ovale curtisi in a rural area of the southeastern region of Ethiopia

Background

Approximately 50 million people (60 %) live in malaria risk areas in Ethiopia, at altitudes below 2000 m. According to official data, 60–70 % of malaria cases are due to Plasmodium falciparum, and 40–30 % by Plasmodium vivax. The species Plasmodium ovale was detected in 2013 in the northwest of the country, being the first report of the presence of this species in Ethiopia since the 60 s. The aim of this study was to assess the diagnosis by microscopy and PCR, and demonstrate the presence of other Plasmodium species in the country.

Methods

The survey was conducted in Bulbula, situated in the Rift Valley (West Arsi Province, Oromia Region). From December 2010 to October 2011, 3060 samples were collected from patients with symptoms of malaria; the diagnosis of malaria was done by microscopy and confirmation by PCR.

Results

736 samples were positive for malaria by microscopy. After removing the 260 samples (109 positives and 151 negatives) for which it was not possible to do PCR, there were a total of 2800 samples, 1209 are used for its confirmation by PCR and quality control (627 are positives and 582 negatives by microscopy). From the 627 positive samples, 604 were confirmed as positive by PCR, 23 false positives were detected, and the group of 582 negative samples, 184 were positive by PCR (false negatives), which added to the previous positive samples is a total of 788, positive samples for some species of Plasmodium sp. 13.3 % more positives were detected with the PCR than the microscopy. Importantly, 23 samples were detected by PCR as P. ovale, after the sequencing of these samples was determined as P. ovale curtisi.

Conclusions

The PCR detected more positive samples than the microscopy; in addition, P. ovale and P. ovale/P. vivax were detected that had not been detected by microscopy, which can affect in the infection control.