Safety and efficacy of re-treatments with pyronaridine-artesunate in African patients with malaria: a substudy of the WANECAM randomised trial

Randomized, placebo-controlled, double-blind phase I trial of co-administered pyronaridine and piperaquine in healthy adults of sub-Saharan origin

Drug resistance to sulfadoxine-pyrimethamine and amodiaquine threatens the efficacy of malaria chemoprevention interventions in children and pregnant women. Combining pyronaridine (PYR) and piperaquine (PQP), both components of approved antimalarial therapies, has the potential to protect vulnerable populations from severe malaria. This randomized, double-blind, placebo-controlled (double-dummy), parallel-group, single site phase I study in healthy adult males or females of Black sub-Saharan African ancestry investigated the safety, tolerability, and pharmacokinetics of PYR + PQP (n = 15), PYR + placebo (n = 8), PQP + placebo (n = 8), and double placebo (n = 6) administered orally once daily for 3 days at the registered dose for the treatment of uncomplicated malaria. All participants completed the study. Forty-five adverse events were reported in 26 participants, most (41/45) were mild/moderate in severity, with no serious adverse events, deaths, or study withdrawals. Adverse events were reported in 66.7% (10/15) of participants administered PYR + PQP, 87.5% (7/8) with PYR + placebo, 50.0% (4/8) with PQP + placebo, and 83.3% (5/6) with placebo. For PYR containing regimens, five of 23 participants had asymptomatic transient increases in alanine and/or aspartate aminotransferase. With PQP containing regimens, four of 23 participants had mild Fridericia-corrected QT interval prolongation. Liver enzyme elevations and prolonged QTc interval were consistent with observations for PYR-artesunate and dihydroartemisinin-PQP, respectively, administered to healthy adults and malaria patients. Increases in PYR and PQP exposures were observed following co-administration versus placebo, with substantial interparticipant variability. The findings suggest that PYR + PQP may have potential in chemoprevention strategies. Further studies are needed in the target populations to assess chemoprotective efficacy and define the benefit-risk profile, with special considerations regarding hepatic and cardiac safety.

Safety and efficacy of pyronaridine-artesunate paediatric granules in the treatment of uncomplicated malaria in children: insights from randomized clinical trials and a real-world study

BACKGROUND

Children are particularly at risk of malaria. This analysis consolidates the clinical data for pyronaridine-artesunate (PA) paediatric granules in children from three randomized clinical trials and a real-world study (CANTAM).

METHODS

An integrated safety analysis of individual patient data from three randomized clinical trials included patients with microscopically-confirmed Plasmodium falciparum, body weight ≥ 5 kg to < 20 kg, who received at least one dose of study drug (paediatric safety population). PA was administered once daily for 3 days; two trials included the comparator artemether-lumefantrine (AL). PCR-adjusted day 28 adequate clinical and parasitological response (ACPR) was evaluated. Real-world PA granules safety and effectiveness was also considered.

RESULTS

In the integrated safety analysis, 63.9% (95% CI 60.2, 67.4; 426/667) of patients had adverse events following PA and 62.0% (95% CI 56.9, 66.9; 222/358) with AL. Vomiting was more common with PA (7.8% [95% CI 6.0, 10.1; 52/667]) than AL (3.4% [95% CI 1.9, 5.8; 12/358]), relative risk 2.3 (95% CI 1.3, 4.3; P = 0.004), occurring mainly following the first PA dose (6.7%, 45/667), without affecting re-dosing or adherence. Prolonged QT interval occurred less frequently with PA (3.1% [95% CI 2.1, 4.8; 21/667]) than AL (8.1% [95% CI 5.7, 11.4; 29/358]), relative risk 0.39 (95% CI 0.22, 0.67; P = 0.0007). In CANTAM, adverse events were reported for 17.7% (95% CI 16.3, 19.2; 460/2599) of patients, most commonly vomiting (5.4% [95% CI 4.6, 6.4; 141/2599]), mainly following the first dose, (4.5% [117/2599]), with all patients successfully re-dosed, and pyrexia (5.4% [95% CI 4.6, 6.3; 140/2599]). In the two comparative clinical trials, Day 28 ACPR in the per-protocol population for PA was 97.1% (95% CI 94.6, 98.6; 329/339) and 100% (95% CI 99.3, 100; 514/514) versus 98.8% (95% CI 95.7, 99.9; 165/167) and 98.4% (95% CI 95.5, 99.7; 188/191) for AL, respectively. In CANTAM, PA clinical effectiveness was 98.0% (95% CI 97.3, 98.5; 2273/2320).

CONCLUSIONS

Anti-malarial treatment with PA paediatric granules administered once daily for 3 days was well tolerated in children and displayed good clinical efficacy in clinical trials, with effectiveness confirmed in a real-world study. Trial registration Clinicaltrials.gov: SP-C-003-05: identifier NCT00331136; SP-C-007-07: identifier NCT0541385; SP-C-021-15: identifier NCT03201770. Pan African Clinical Trials Registry: SP-C-013-11: identifier PACTR201105000286876.

Pyronaridine: a review of its clinical pharmacology in the treatment of malaria

Pyronaridine-artesunate was recently strongly recommended in the 2022 update of the WHO Guidelines for the Treatment of Malaria, becoming the newest artemisinin-based combination therapy (ACT) for both uncomplicated Plasmodium falciparum and Plasmodium vivax malaria. Pyronaridine-artesunate, available as a tablet and paediatric granule formulations, is being adopted in regions where malaria treatment outcome is challenged by increasing chloroquine resistance. Pyronaridine is an old antimalarial agent that has been used for more than 50 years as a blood schizonticide, which exerts its antimalarial activity by interfering with the synthesis of the haemozoin pigment within the Plasmodium digestive vacuole. Pyronaridine exhibits a high blood-to-plasma distribution ratio due to its tendency to accumulate in blood cells. This feature is believed to play a crucial role in its pharmacokinetic (PK) properties and pharmacological activity. The PK characteristics of pyronaridine include rapid oral absorption, large volumes of distribution and low total body clearance, resulting in a long terminal apparent half-life. Moreover, differences in PK profiles have been observed between healthy volunteers and malaria-infected patients, indicating a potential disease-related impact on PK properties. Despite a long history, there is only limited knowledge of the clinical PK and pharmacodynamics of pyronaridine, particularly in special populations such as children and pregnant women. We here provide a comprehensive overview of the clinical pharmacology of pyronaridine in the treatment of malaria.

Therapeutic efficacy of pyronaridine-artesunate (Pyramax®) against uncomplicated Plasmodium falciparum infection at Hamusit Health Centre, Northwest Ethiopia

BACKGROUND

Early case detection and prompt treatment are important malaria control and elimination strategies. However, the emergence and rapid spread of drug-resistant strains present a major challenge. This study reports the first therapeutic efficacy profile of pyronaridine-artesunate against uncomplicated Plasmodium falciparum in Northwest Ethiopia.

METHODS

This single-arm prospective study with 42-day follow-up period was conducted from March to May 2021 at Hamusit Health Centre using the World Health Organization (WHO) therapeutic efficacy study protocol. A total of 90 adults ages 18 and older with uncomplicated falciparum malaria consented and were enrolled in the study. A standard single-dose regimen of pyronaridine-artesunate was administered daily for 3 days, and clinical and parasitological outcomes were assessed over 42 days of follow-up. Thick and thin blood films were prepared from capillary blood and examined using light microscopy. Haemoglobin was measured and dried blood spots were collected on day 0 and on the day of failure.

RESULTS

Out of 90 patients, 86/90 (95.6%) completed the 42-day follow-up study period. The overall PCR-corrected cure rate (adequate clinical and parasitological response) was very high at 86/87 (98.9%) (95% CI: 92.2-99.8%) with no serious adverse events. The parasite clearance rate was high with fast resolution of clinical symptoms; 86/90 (95.6%) and 100% of the study participants cleared parasitaemia and fever on day 3, respectively.

CONCLUSION

Pyronaridine-artesunate was highly efficacious and safe against uncomplicated P. falciparum in this study population.

Efficacy and safety of pyronaridine-artesunate versus artemether-lumefantrine in the treatment of acute uncomplicated malaria in children in South-West Nigeria: an open-labelled randomized controlled trial

BACKGROUND

In Nigeria, declining responsiveness to artemether-lumefantrine (AL), the artemisinin-based combination therapy (ACT) of choice since 2005, has been reported. Pyronaridine-artesunate (PA) is a newer fixed-dose ACT recently prequalified by the WHO for the treatment of uncomplicated falciparum malaria. However, PA data from the Nigerian pediatric population is scarce. Therefore, the efficacy and safety of PA and AL using the WHO 28-day anti-malarial therapeutic efficacy study protocol in Ibadan, southwest Nigeria, were compared.

METHODS

In an open-labelled, randomized, controlled clinical trial, 172 children aged 3-144 months with a history of fever and microscopically confirmed uncomplicated Plasmodium falciparum malaria were enrolled in southwest Nigeria. Enrollees were randomly assigned to receive PA or AL at standard dosages according to body weight for 3 days. Venous blood was obtained for hematology, blood chemistry, and liver function tests on days 0, 3, 7, and 28 as part of the safety evaluation.

RESULTS

165 (95.9%) of the enrolled individuals completed the study. About half (52.3%; 90/172) of enrollees were male. Eighty-seven (50.6%) received AL, while 85 (49.4%) received PA. Day 28, adequate clinical and parasitological response for PA was 92.7% [(76/82) 95% CI 83.1, 95.9] and 71.1% [(59/83) 95% CI 60.4, 79.9] for AL (0.001). Fever and parasite clearance were similar in both groups. Two of six and eight of 24 parasite recurrences were observed among PA- and AL-treated children, respectively. PCR-corrected Day-28 cure rates for PA were 97.4% (76/78) and 88.1% (59/67) for AL (= 0.04) in the per-protocol population after new infections were censored. Hematological recovery at day 28 was significantly better among PA-treated patients (34.9% 2.8) compared to those treated with AL (33.1% 3.0) (0.002). Adverse events in both treatment arms were mild and similar to the symptoms of malaria infection. Blood chemistry and liver function tests were mostly within normal limits, with an occasional marginal rise.

CONCLUSION

PA and AL were well-tolerated. PA was significantly more efficacious than AL in both the PCR-uncorrected and PCR-corrected per-protocol populations during this study. The results of this study support the inclusion of PA in the anti-malarial treatment guidelines in Nigeria.

RETROSPECTIVE TRIAL REGISTRATION

Clinicaltrials.gov: NCT05192265.

Feasibility and Acceptability of a Strategy Deploying Multiple First-Line Artemisinin-Based Combination Therapies for Uncomplicated Malaria in the Health District of Kaya, Burkina Faso

(1) Background: Effective malaria case management relies on World Health Organization (WHO) recommended artemisinin-based combination therapies (ACTs), but partial resistance to artemisinin has emerged and is spreading, threatening malaria control and elimination efforts. The strategy of deploying multiple first-line therapies (MFT) may help mitigate this threat and extend the therapeutic life of current ACTs. (2) Methods: A district-wide pilot quasi-experimental study was conducted, deploying three different ACTs at the public health facility (PHF) level for uncomplicated malaria treatment from December 2019 to December 2020 in the health district (HD) of Kaya, Burkina Faso. Mixed methods, including household and health facility-based quantitative and qualitative surveys, were used to evaluate the pilot programme. (3) Results: A total of 2008 suspected malaria patients were surveyed at PHFs, of which 79.1% were tested by rapid diagnostic test (RDT) with 65.5% positivity rate. In total, 86.1% of the confirmed cases received the appropriate ACT according to the MFT strategy. The adherence level did not differ by study segment (p = 0.19). Overall, the compliance level of health workers (HWs) with MFT strategy was 72.7% (95% CI: 69.7–75.5). The odds of using PHF as the first source of care increased after the intervention (aOR = 1.6; 95% CI, 1.3–1.9), and the reported adherence to the 3-day treatment regimen was 82.1%; (95% CI: 79.6–84.3). Qualitative results showed a high acceptance of the MFT strategy with positive opinions from all stakeholders. (4) Conclusions: Implementing an MFT strategy is operationally feasible and acceptable by stakeholders in the health systems in Burkina Faso. This study provides evidence to support the simultaneous use of multiple first-line artemisinin combination therapies in malaria-endemic countries such as Burkina Faso.

Efficacy and safety of pyronaridine-artesunate (Pyramax®) for the treatment of uncomplicated Plasmodium vivax malaria in Northwest Ethiopia

BACKGROUND

Declining efficacy of chloroquine for the treatment Plasmodium vivax malaria has been reported in different endemic settings in Ethiopia. This highlights the need to assess alternative options for P. vivax treatment with artemisinin-based combination therapy, such as pyronaridine-artesunate. This treatment regimen has shown high efficacy for uncomplicated malaria in both Africa and Asia. However, limited data are available from Ethiopia. This study was conducted to assess the efficacy and safety of pyronaridine-artesunate for the treatment of uncomplicated P. vivax malaria in Northwest Ethiopia.

METHODS

A single arm prospective efficacy study was conducted in the Hamusite area, Northwest Ethiopia. Fifty-one febrile adult patients with uncomplicated P. vivax malaria were enrolled between March and July 2021. Patients were treated with pyronaridine-artesunate once daily for three days. Clinical and parasitological parameters were monitored over a 42-day follow-up period using the standard World Health Organization protocol for therapeutic efficacy studies.

RESULTS

A total of 4372 febrile patients were screened with 51 patients enrolled and 49 completing the 42-day follow-up period. The PCR-uncorrected adequate clinical and parasitological response (ACPR) was 95.9% (47/49; 95% CI 84.9-99.0) on day 42. Two patients had recurrences [4.0% (2/49); 95% CI 0.7-12.1] on days 35 and 42. The parasite clearance rate was rapid with fast resolution of clinical symptoms; 100% of participants had cleared parasitaemia on day 1 and fever on day 2. All 16 (31.4%) patients with gametocyte carriage on day 0 had cleared by day 1. There were no serious adverse events.

CONCLUSION

In this small study, pyronaridine-artesunate was efficacious and well-tolerated for the treatment of uncomplicated P. vivax malaria. In adults in the study setting, it would be a suitable alternative option for case management.

A Novel Ex Vivo Drug Assay for Assessing the Transmission-Blocking Activity of Compounds on Field-Isolated Plasmodium falciparum Gametocytes

The discovery and development of transmission-blocking therapies challenge malaria elimination and necessitate standard and reproducible bioassays to measure the blocking properties of antimalarial drugs and candidate compounds. Most of the current bioassays evaluating the transmission-blocking activity of compounds rely on laboratory-adapted Plasmodium strains. Transmission-blocking data from clinical gametocyte isolates could help select novel transmission-blocking candidates for further development. Using freshly collected Plasmodium falciparum gametocytes from asymptomatic individuals, we first optimized ex vivo culture conditions to improve gametocyte viability and infectiousness by testing several culture parameters. We next pre-exposed ex vivo field-isolated gametocytes to chloroquine, dihydroartemisinin, primaquine, KDU691, GNF179, and oryzalin for 48 h prior to direct membrane feeding. We measured the activity of the drug on the ability of gametocytes to resume the sexual life cycle in Anopheles after drug exposure. Using 57 blood samples collected from Malian volunteers aged 6 to 15 years, we demonstrate that the infectivity of freshly collected field gametocytes can be preserved and improved ex vivo in a culture medium supplemented with 10% horse serum at 4% hematocrit for 48 h. Moreover, our optimized drug assay displays the weak transmission-blocking activity of chloroquine and dihydroartemisinin, while primaquine and oryzalin exhibited a transmission-blocking activity of ~50% at 1 μM. KDU691 and GNF179 both interrupted Plasmodium transmission at 1 μM and 5 nM, respectively. This new approach, if implemented, has the potential to accelerate the screening of compounds with transmission-blocking activity.

Antimalarial treatment in infants

INTRODUCTION

Malaria in infants is common in high-transmission settings, especially in infants >6 months. Infants undergo physiological changes impacting pharmacokinetics and pharmacodynamics of anti-malarial drugs and, consequently, the safety and efficacy of malaria treatment. Yet, treatment guidelines and evidence on pharmacological interventions for malaria often fail to address this vulnerable age-group. This review aims to summarise the available data on anti-malarial treatment in infants.

AREAS COVERED

The standard recommended treatments for severe and uncomplicated malaria are generally safe and effective in infants. However, infants have an increased risk of drug-related vomiting and have distinct pharmacokinetic parameters of antimalarials compared with older patients. These include larger volumes of distribution, higher clearance rates and immature enzyme systems. Consequently, infants with malaria may be at increased risk of treatment failure and drug toxicity.

EXPERT OPINION

Knowledge expansion to optimize treatment can be achieved by including more infants in antimalarial drug trials and by reporting separately on treatment outcomes in infants. Additional evidence on the efficacy, safety, tolerability, acceptability and effectiveness of ACTs in infants is needed, as well as population pharmacokinetics studies on antimalarials in the infant population.

Prospective observational study to evaluate the clinical and biological safety profile of pyronaridine-artesunate in a rural health district in Burkina Faso

The assessment in real‐life conditions of the safety and efficacy of new antimalarial drugs is of greatest interest. This study aimed to monitor and evaluate both clinical and biological safety of pyronaridine‐artesunate (PA) in real‐life conditions in Burkina Faso's health system. This was a single‐arm, open‐label study, where patients attending Nanoro health facilities with uncomplicated malaria were consented to be part of a cohort event monitoring (CEM). At inclusion (day‐0), PA was administered orally once a day for 3 days. Patients spontaneous reported any clinical adverse events (AEs) occurring within 28 days following the treatment. Additionally, the study focused on AEs of special interest (AESI), namely clinical signs related to hepatotoxicity and increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST). A nested subset of patients with blood sample collection at day‐0 and day‐7 were monitored to investigate the effect of PA on biochemistry parameters. From September 2017 to October 2018, 2786 patients were treated with PA. About 97.8% (2720/2786) of patients did not report any AE. The most commonly reported events were respiratory, thoracic, and mediastinal disorders (8.3 per 1000), infections and infestations (7.9 per 1000), and gastrointestinal disorders (7.2 per 1000). No clinical or biological hepatotoxicity event related to PA was reported during the follow‐up. Changes in biochemistry parameters remained within laboratory reference ranges. The study showed that PA is a well‐tolerated drug and should be considered as a good option by malaria control programs in countries where existing first‐line antimalarial drugs are continuously threatened by the emergence of drug resistance.

Pyronaridine-artesunate for treating uncomplicated Plasmodium falciparum malaria

BACKGROUND

The World Health Organization (WHO) recommends artemisinin-based combination therapies (ACTs) to treat uncomplicated Plasmodium falciparum malaria. Concerns about artemisinin resistance have led to global initiatives to develop new partner drugs to protect artemisinin derivatives in ACT. Pyronaridine-artesunate is a novel ACT.

OBJECTIVES

To evaluate the efficacy of pyronaridine-artesunate compared to alternative ACTs for treating people with uncomplicated P falciparum malaria, and to evaluate the safety of pyronaridine-artesunate and other pyronaridine treatments compared to alternative treatments.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; Embase; and LILACS. We also searched ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, and the ISRCTN registry for ongoing or recently completed trials. The date of the last search was 27 October 2021.

SELECTION CRITERIA

For the efficacy analysis, we included randomized controlled trials (RCTs) of pyronaridine-artesunate for treating uncomplicated P falciparum malaria. For the safety analysis, we included RCTs that used pyronaridine alone or in combination with any other antimalarials. In addition to these analyses, we conducted a separate systematic review summarizing data on safety from non-randomized studies (NRS) of any patient receiving pyronaridine (NRS safety review).  DATA COLLECTION AND ANALYSIS: Two review authors independently extracted all data and assessed the certainty of the evidence. We meta-analysed data to calculate risk ratios (RRs) for treatment failures between comparisons, and for safety outcomes between and across comparisons.

MAIN RESULTS

We included 10 relevant RCTs. Seven RCTs were co-funded by Shin Poong Pharmaceuticals, and three were funded by government agencies. Efficacy analysis (RCTs) For the efficacy analysis, we identified five RCTs comprising 5711 participants. This included 4465 participants from 13 sites in Africa, and 1246 participants from five sites in Asia. The analysis included 541 children aged less than five years. Overall, pyronaridine-artesunate had a polymerase chain reaction (PCR)-adjusted treatment failure rate of less than 5%. We evaluated pyronaridine-artesunate versus the following. • Artemether-lumefantrine. Pyronaridine artesunate may perform better for PCR-adjusted failures at day 28 (RR 0.59, 95% confidence interval (CI) 0.26 to 1.31; 4 RCTs, 3068 participants, low-certainty evidence); for unadjusted failures at day 28 (RR 0.27, 95% CI 0.13 to 0.58; 4 RCTs, 3149 participants, low-certainty evidence); and for unadjusted failures at day 42 (RR 0.61, 95% CI 0.46 to 0.82; 4 RCTs, 3080 participants, low-certainty evidence). For PCR-adjusted failures at day 42, there may be little or no difference between groups (RR 0.86, 95% CI 0.49 to 1.51; 4 RCTs, 2575 participants, low-certainty evidence). • Artesunate-amodiaquine. Pyronaridine artesunate may perform better for PCR-adjusted failures at day 28 (RR 0.55, 95% CI 0.11 to 2.77; 1 RCT, 1245 participants, low-certainty evidence); probably performs better for unadjusted failures at day 28 (RR 0.49, 95% CI 0.30 to 0.81; 1 RCT, 1257 participants, moderate-certainty evidence); may make little or no difference for PCR-adjusted failures at day 42 (RR 0.98, 95% CI 0.20 to 4.83; 1 RCT, 1091 participants, low-certainty evidence); and probably makes little or no difference for unadjusted failures at day 42 (RR 0.98, 95% CI 0.78 to 1.23; 1 RCT, 1235 participants, moderate-certainty evidence). • Mefloquine plus artesunate. Pyronaridine artesunate may perform better for PCR-adjusted failures at day 28 (RR 0.37, 95% CI 0.13 to 1.05; 1 RCT, 1117 participants, low-certainty evidence); probably performs better for unadjusted failures at day 28 (RR 0.36, 95% CI 0.17 to 0.78; 1 RCT, 1120 participants, moderate-certainty evidence); may make little or no difference for unadjusted failures at day 42 (RR 0.84, 95% CI 0.54 to 1.31; 1 RCT, 1059 participants, low-certainty evidence); but may lead to higher PCR-adjusted failures at day 42 (RR 1.80, 95% CI 0.90 to 3.57; 1 RCT, 1037 participants, low-certainty evidence). Safety analysis (RCTs) For the RCT safety analysis, we identified eight RCTs, one of which was delineated by study site, comparing pyronaridine-artesunate to other antimalarials. Pyronaridine-artesunate was associated with raised liver enzymes compared to other antimalarials: alanine aminotransferase (ALT) (RR 3.59, 95% CI 1.76 to 7.33; 8 RCTS, 6669 participants, high-certainty evidence) and aspartate transaminase (AST) (RR 2.22, 95% CI 1.12 to 4.41; 8 RCTs, 6669 participants, moderate-certainty evidence). No such effect was demonstrated with bilirubin (RR 1.03, 95% CI 0.49 to 2.18; 7 RCTs, 6384 participants, moderate-certainty evidence). There was one reported case in which raised ALT occurred with raised bilirubin. No study reported severe drug-induced liver injury. Electrocardiograph (ECG) abnormalities were less common with pyronaridine-artesunate compared to other antimalarials. We identified no other safety concerns. NRS safety review A review on safety in NRS allowed us to increase the population within which safety was assessed. We included seven studies with 9546 participants: five single-arm observational studies, one cohort event monitoring study, and one dose-escalation study. All studies provided data on adverse event frequency, with a small number of participants experiencing serious adverse events and adverse effects related to pyronaridine: serious adverse events average 0.37%; drug-related 9.0%. In two studies reporting elevations in liver enzymes, small percentages of participants (2.4% and 14.1% respectively) experienced increases in either ALT, AST, or bilirubin on day 7; however, these were small increases that returned to normal by day 42.  AUTHORS' CONCLUSIONS: Pyronaridine-artesunate was efficacious against uncomplicated P falciparum malaria; achieved a PCR-adjusted treatment failure rate of less than 5% at days 28 and 42; and may be at least as good as, or better than, other marketed ACTs. Pyronaridine-artesunate increases the risk of episodes of abnormally raised ALT. The observational data did not signal an excess of clinically important adverse effects.

Attitudes, practices, and determinants of community care-seeking behaviours for fever/malaria episodes in the context of the implementation of multiple first-line therapies for uncomplicated malaria in the health district of Kaya, Burkina Faso

Background

Malaria case management relies on World Health Organization (WHO)-recommended artemisinin-based combination therapy (ACT), and a continuous understanding of local community knowledge, attitudes, and practices may be a great support for the success of malaria disease control efforts. In this context, this study aimed to identify potential facilitators or barriers at the community level to inform a health district-wide implementation of multiple first-line therapies (MFT) as a new strategy for uncomplicated malaria case management.

Methods

A community-based cross-sectional study using a mixed-method design was carried out from November 2018 to February 2019, in the health district (HD) of Kaya in Burkina Faso. Quantitative data were collected using a standardized questionnaire from 1394 individuals who had fever/malaria episodes four weeks prior to the survey. In addition, 23 focus group discussions (FGDs) were conducted targeting various segments of the community. Logistic regression models were used to assess the predictors of community care-seeking behaviours.

Results

Overall, 98% (1366/1394) of study participants sought advice or treatment, and 66.5% did so within 24 h of fever onset. 76.4% of participants preferred to seek treatment from health centres as the first recourse to care, 5.8% were treated at home with remaining drug stock, and 2.3% preferred traditional healers. Artemether-lumefantrine (AL) was by far the most used anti-malarial drug (98.2%); reported adherence to the 3-day treatment regimen was 84.3%. Multivariate analysis identified less than 5 km distance travelled for care (AOR = 2.7; 95% CI 2.1–3.7) and education/schooling (AOR = 1.8; 95% CI 1.3–2.5) as determinants of prompt care-seeking for fever. Geographical proximity (AOR = 1.5, 95% CI 1.2–2.1), having a child under five (AOR = 4.6, 95% CI 3.2–6.7), being pregnant (AOR = 6.5, 95% CI 1.9–22.5), and living in an urban area (AOR = 2.8, 95% CI 1.8–4.2) were significant predictors for visiting health centres. The FGDs showed that participants had good knowledge about malaria symptoms, prevention tools, and effective treatment. Behaviour change regarding malaria treatment and free medication for children under five were the main reasons for participants to seek care at health centres.

Conclusions

The study showed appropriate knowledge about malaria and positive community care-seeking behaviour at health centres for fever/malaria episodes. This could potentially facilitate the implementation of a MFT pilot programme in the district.

ClinicalTrials.gov Identifier: NCT04265573.

Opportunities for enteral drug delivery for neonates, infants and toddlers: a critical exploration

INTRODUCTION

The field of neonatal, infant and toddler pharmaceutical development is constantly improving, however a lag still remains in comparison to older children and adults. Their rapid anatomical, physiological and behavioural developmental rates pose extra challenges in diagnosing, treating, or preventing their disease. In turn, this brings complexity in formulating truly age-appropriate medicinal products that suit this heterogeneous paediatric subset. Progress in the availability of such products has ensued following the introduction of the 2007 European Union Paediatric Regulation, and in recent years, oral multiparticulate and dispersible solid formulations have gained interest alongside liquid formulations. However, the need is still great for dosage forms that do not compromise on pharmaceutical efficacy, safety and global accessibility in those aged under 2.

AREAS COVERED

This article highlights some of the formulation challenges correlated with this age group and critically explores recent solid age-appropriate formulations and their administration devices for enteral drug delivery.

EXPERT OPINION

There are many formulation requirements to consider when formulating drug products for children aged under 2. Efforts are required into understanding acceptability in this age group and of their carers, and whether innovation or optimisation is required, to help guide formulators towards optimal approaches without impacting access.

Efficacy, Safety and Tolerability of Pyronaridine-artesunate in Asymptomatic Malaria-infected Individuals: a Randomized Controlled Trial

BACKGROUND

Pyronaridine-artesunate (PA) is a registered artemisinin-based combination therapy, potentially useful for mass drug administration campaigns. However, further data are needed to evaluate its efficacy, safety and tolerability as full or incomplete treatment in asymptomatic Plasmodium falciparum-infected individuals.

METHODS

This phase II, multi-center, open label, randomized clinical trial was conducted in The Gambia and Zambia. Participants with microscopically confirmed asymptomatic P. falciparum infection were randomly assigned (1:1:1) to receive a 3-day, 2-day, or 1-day treatment regimen of PA (180:60 mg), dosed according to bodyweight. The primary efficacy outcome was polymerase chain reaction (PCR)-adjusted adequate parasitological response (APR) at day 28 in the per-protocol population.

RESULTS

A total of 303 participants were randomized. Day 28 PCR-adjusted APR was 100% for both the 3-day (98/98) and 2-day regimens (96/96), and 96.8% (89/94) for the 1-day regimen. Efficacy was maintained at 100% until day 63 for the 3-day and 2-day regimens but declined to 94.4% (84/89) with the 1-day regimen. Adverse event frequency was similar between the 3-day (51.5% [52/101]), 2-day (52.5% [52/99]), and 1-day (54.4% [56/103]) regimens; the majority of adverse events were of grade 1 or 2 severity (85% [136/160]). Asymptomatic, transient increases (>3 times the upper limit of normal) in alanine aminotransferase/aspartate aminotransferase were observed for 6/301 (2.0%) participants.

CONCLUSIONS

PA had high efficacy and good tolerability in asymptomatic P. falciparum-infected individuals, with similar efficacy for the full 3-day and incomplete 2-day regimens. Although good adherence to the 3-day regimen should be encouraged, these results support the further investigation of PA for mass drug administration campaigns.

CLINICAL TRIALS REGISTRATION

NCT03814616.

An update on pharmacogenetic factors influencing the metabolism and toxicity of artemisinin-based combination therapy in the treatment of malaria

INTRODUCTION

Artemisinin-based combination therapies (ACTs) are recommended first-line antimalarials for uncomplicated Plasmodium falciparum malaria. Pharmacokinetic/pharmacodynamic variation associated with ACT drugs and their effect is documented. It is accepted to an extent that inter-individual variation is genetically driven, and should be explored for optimized antimalarial use.

AREAS COVERED

We provide an update on the pharmacogenetics of ACT antimalarial disposition. Beyond presently used antimalarials, we also refer to information available for the most notable next-generation drugs under development. The bibliographic approach was based on multiple Boolean searches on PubMed covering all recent publications since our previous review.

EXPERT OPINION

The last 10 years have witnessed an increase in our knowledge of ACT pharmacogenetics, including the first clear examples of its contribution as an exacerbating factor for drug-drug interactions. This knowledge gap is still large and is likely to widen as a new wave of antimalarial drug is looming, with few studies addressing their pharmacogenetics. Clinically useful pharmacogenetic markers are still not available, in particular, from an individual precision medicine perspective. A better understanding of the genetic makeup of target populations can be valuable for aiding decisions on mass drug administration implementation concerning region-specific antimalarial drug and dosage options.

Antimalarials for children with Plasmodium vivax infection: Current status, challenges, and research priorities

The aim of this narrative review is to summarise efficacy and pharmacokinetic data for Plasmodium vivax in children. The burden of P. vivax malaria in children continues to remain a significant public health issue, and the need for improved treatment regimens for this vulnerable population is critical. Relapse after re-activation of dormant liver-stage hypnozoites poses additional challenges for treatment, elimination, and control strategies for P. vivax. Whilst it is recognised that paediatric pharmacology may be significantly influenced by anatomical and physiological changes of childhood, dosing regimens often continue to be extrapolated from adult data, highlighting the need for antimalarial dosing in children to be evaluated in early phase clinical trials. This will ensure that globally recommended treatment regimens do not result in suboptimal dosing in children. Furthermore, the development of affordable paediatric formulations to enhance treatment acceptability and widespread G6PD testing to facilitate use of anti-hypnozoite treatment such as primaquine and tafenoquine, should be further prioritised. As the world prepares for malaria elimination, a renewed focus on P. vivax malaria provides an ideal opportunity to harness momentum and ensure that all populations, including children have access to safe, efficacious, and correctly dosed antimalarial therapies.

Artemisinin-based combination therapy for uncomplicated Plasmodium falciparum malaria in Mali: a systematic review and meta-analysis

BACKGROUND

Artemisinin-based combination therapy (ACT) was deployed in 2005 as an alternative to chloroquine and is considered the most efficacious treatment currently available for uncomplicated falciparum malaria. While widespread artemisinin resistance has not been reported to date in Africa, recent studies have reported partial resistance in Rwanda. The purpose of this study is to provide a current systematic review and meta-analysis on ACT at Mali study sites, where falciparum malaria is highly endemic.

METHODS

A systematic review of the literature maintained in the bibliographic databases accessible through the PubMed, ScienceDirect and Web of Science search engines was performed to identify research studies on ACT occurring at Mali study sites. Selected studies included trials occurring at Mali study sites with reported polymerase chain reaction (PCR)-corrected adequate clinical and parasite response rates (ACPRcs) at 28 days. Data were stratified by treatment arm (artemether-lumefantrine (AL), the first-line treatment for falciparum malaria in Mali and non-AL arms) and analysed using random-effects, meta-analysis approaches.

RESULTS

A total of 11 studies met the inclusion criteria, and a risk of bias assessment carried out by two independent reviewers determined low risk of bias among all assessed criteria. The ACPRc for the first-line AL at Mali sites was 99.0% (95% CI (98.3%, 99.8%)), while the ACPRc among non-AL treatment arms was 98.9% (95% CI (98.3%, 99.5%)). The difference in ACPRcs between non-AL treatment arms and AL treatment arms was not statistically significant (p = .752), suggesting that there are potential treatment alternatives beyond the first-line of AL in Mali.

CONCLUSIONS

ACT remains highly efficacious in treating uncomplicated falciparum malaria in Mali. Country-specific meta-analyses on ACT are needed on an ongoing basis for monitoring and evaluating drug efficacy patterns to guide local malaria treatment policies, particularly in the wake of observed artemisinin resistance in Southeast Asia and partial resistance in Rwanda.

Pyronaridine-artesunate real-world safety, tolerability, and effectiveness in malaria patients in 5 African countries: A single-arm, open-label, cohort event monitoring study

BACKGROUND

In Phase II/III randomized controlled clinical trials for the treatment of acute uncomplicated malaria, pyronaridine-artesunate demonstrated high efficacy and a safety profile consistent with that of comparators, except that asymptomatic, mainly mild-to-moderate transient increases in liver aminotransferases were reported for some patients. Hepatic safety, tolerability, and effectiveness have not been previously assessed under real-world conditions in Africa.

METHODS AND FINDINGS

This single-arm, open-label, cohort event monitoring study was conducted at 6 health centers in Cameroon, Democratic Republic of Congo, Gabon, Ivory Coast, and Republic of Congo between June 2017 and April 2019. The trial protocol as closely as possible resembled real-world clinical practice for the treatment of malaria at the centers. Eligible patients were adults or children of either sex, weighing at least 5 kg, with acute uncomplicated malaria who did not have contraindications for pyronaridine-artesunate treatment as per the summary of product characteristics. Patients received fixed-dose pyronaridine-artesunate once daily for 3 days, dosed by body weight, without regard to food intake. A tablet formulation was used in adults and adolescents and a pediatric granule formulation in children and infants under 20 kg body weight. The primary outcome was the hepatic event incidence, defined as the appearance of the clinical signs and symptoms of hepatotoxicity confirmed by a >2× rise in alanine aminotransferase/aspartate aminotransferase (ALT/AST) versus baseline in patients with baseline ALT/AST >2× the upper limit of normal (ULN). As a secondary outcome, this was assessed in patients with ALT/AST >2× ULN prior to treatment versus a matched cohort of patients with normal baseline ALT/AST. The safety population comprised 7,154 patients, of mean age 13.9 years (standard deviation (SD) 14.6), around half of whom were male (3,569 [49.9%]). Patients experienced 8,560 malaria episodes; 158 occurred in patients with baseline ALT/AST elevations >2×ULN. No protocol-defined hepatic events occurred following pyronaridine-artesunate treatment of malaria patients with or without baseline hepatic dysfunction. Thus, no cohort comparison could be undertaken. Also, as postbaseline clinical chemistry was only performed where clinically indicated, postbaseline ALT/AST levels were not systematically assessed for all patients. Adverse events of any cause occurred in 20.8% (1,490/7,154) of patients, most frequently pyrexia (5.1% [366/7,154]) and vomiting (4.2% [303/7,154]). Adjusting for Plasmodium falciparum reinfection, clinical effectiveness at day 28 was 98.6% ([7,369/7,746] 95% confidence interval (CI) 98.3 to 98.9) in the per-protocol population. There was no indication that comorbidities or malnutrition adversely affected outcomes. The key study limitation was that postbaseline clinical biochemistry was only evaluated when clinically indicated.

CONCLUSIONS

Pyronaridine-artesunate had good tolerability and effectiveness in a representative African population under conditions similar to everyday clinical practice. These findings support pyronaridine-artesunate as an operationally useful addition to the management of acute uncomplicated malaria.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03201770.

Therapeutic efficacy of artemether-lumefantrine and artesunate-amodiaquine for the treatment of uncomplicated Plasmodium falciparum malaria in Mali, 2015-2016

BACKGROUND

The current first-line treatments for uncomplicated malaria recommended by the National Malaria Control Programme in Mali are artemether-lumefantrine (AL) and artesunate-amodiaquine (ASAQ). From 2015 to 2016, an in vivo study was carried out to assess the clinical and parasitological responses to AL and ASAQ in Sélingué, Mali.

METHODS

Children between 6 and 59 months of age with uncomplicated Plasmodium falciparum infection and 2000-200,000 asexual parasites/μL of blood were enrolled, randomly assigned to either AL or ASAQ, and followed up for 42 days. Uncorrected and PCR-corrected efficacy results at days 28 and 42. were calculated. Known markers of resistance in the Pfk13, Pfmdr1, and Pfcrt genes were assessed using Sanger sequencing.

RESULTS

A total of 449 patients were enrolled: 225 in the AL group and 224 in the ASAQ group. Uncorrected efficacy at day 28 was 83.4% (95% CI 78.5-88.4%) in the AL arm and 93.1% (95% CI 89.7-96.5%) in the ASAQ arm. The per protocol PCR-corrected efficacy at day 28 was 91.0% (86.0-95.9%) in the AL arm and 97.1% (93.6-100%) in the ASAQ arm. ASAQ was significantly (p < 0.05) better than AL for each of the aforementioned efficacy outcomes. No mutations associated with artemisinin resistance were identified in the Pfk13 gene. Overall, for Pfmdr1, the N86 allele and the NFD haplotype were the most common. The NFD haplotype was significantly more prevalent in the post-treatment than in the pre-treatment isolates in the AL arm (p < 0.01) but not in the ASAQ arm. For Pfcrt, the CVIET haplotype was the most common.

CONCLUSIONS

The findings indicate that both AL and ASAQ remain effective for the treatment of uncomplicated malaria in Sélingué, Mali.

Artesunate attenuates proliferation of epithelial cells by downregulating the NF-κB and AKT signaling pathways in benign mammary gland hyperplasia rats

Background

The aim of this study was to investigate the effects of artesunate (ART) on breast epithelial cell proliferation in vitro and in vivo.

Methods

Immortalized human non-cancer mammary epithelial (MCF-10A) cells were used to determine the effect of ART on estrogen-induced mammary hyperplasia cells. We investigated the effect of ART on the synthesis of cyclooxygenase-2 (COX-2) and proliferating cell nuclear antigen (PCNA) in MCF-10A by treating MCF-10A 36 h with different concentrations of ART (0, 100, 200, 400 µm, n=12/group). We then investigated the effect of ART on estrogen induced COX-2, PCNA, nuclear factor-kappa B (NF-κB), and pNF-κB synthesis by treating MCF-10A with both estrogen and ART (0, 50, 100, 200 µm, n=12/group). A mammary hyperplasia model (MGH) was established in rats. All rats (n=12) were divided into 4 groups [group A: negative control (NC) + Art −; group B: NC + Art +; group C: MGH + Art −; group D: MGH + Art +] by the random number table method and the effects of ART on estradiol-induced mammary hyperplasia, fibrosis, and phosphorylation of AKT and NF-κB were studied by histopathological staining, Masson trichrome staining, immunohistochemistry (IHC), and western blotting.

Results

The proliferation and inflammation of mammary epithelial cells were blocked by ART (P<0.05). The phosphorylation of NF-κB induced by estradiol in MCF-10A was attenuated by ART (P<0.05). In the rat MGH, ART reduced cell proliferation and fibrosis (P<0.05) and inhibited the phosphorylation of AKT and NF-κB (P<0.05).

Conclusions

The drug ART inhibits estrogen-induced breast hyperplasia by blocking AKT and NFkB phosphorylation.

Protocol for a quasi-experimental study to assess the feasibility, acceptability and costs of multiple first-lines artemisinin-based combination therapies for uncomplicated malaria in the Kaya health district, Burkina Faso

INTRODUCTION

As demonstrated in mathematical models, the simultaneous deployment of multiple first-line therapies (MFT) for uncomplicated malaria, using artemisinin-based combination therapies (ACTs), may extend the useful therapeutic life of the current ACTs. This is possible by reducing drug pressure and slowing the spread of resistance without putting patients' life at risk. We hypothesised that a simultaneous deployment of three different ACTs is feasible, acceptable and can achieve high coverage rate if potential barriers are properly identified and addressed.

METHODS AND ANALYSIS

We plan to conduct a quasi-experimental study in the Kaya health district in Burkina Faso. We will investigate a simultaneous deployment of three ACTs, artemether-lumefantrine, pyronaridine-artesunate, dihydroartesinin-piperaquine, targeting three segments of the population: pregnant women, children under five and individuals aged five years and above. The study will include four overlapping phases: the formative phase, the MFT deployment phase, the monitoring and evaluation phase and the post-evaluation phase. The formative phase will help generate baseline information and develop MFT deployment tools. It will be followed by the MFT deployment phase in the study area. The monitoring and evaluation phase will be conducted as the deployment of MFT progresses. Cross-sectional surveys including desk reviews as well as qualitative and quantitative research methods will be used to assess the study outcomes. Quantitatives study outcomes will be measured using univariate, bivariate and multivariate analysis, including logistic regression and interrupted time series analysis approach. Content analysis will be performed on the qualitative data.

ETHICS AND DISSEMINATION

The Health Research Ethics Committee in Burkina Faso approved the study (Clearance no. 2018-8-113). Study findings will be disseminated through feedback meetings with local communities, national workshops, oral presentations at congresses, seminars and publications in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT04265573.

Hepatic safety of repeated treatment with pyronaridine-artesunate versus artemether-lumefantrine in patients with uncomplicated malaria: a secondary analysis of the WANECAM 1 data from Bobo-Dioulasso, Burkina Faso

Background

The use of pyronaridine-artesunate (PA) has been associated with scarce transaminitis in patients. This analysis aimed to evaluate the hepatic safety profile of repeated treatment with PA versus artemether–lumefantrine (AL) in patients with consecutive uncomplicated malaria episodes in Bobo-Dioulasso, Burkina Faso.

Methods

This study analysed data from a clinical trial conducted from 2012 to 2015, in which participants with uncomplicated malaria were assigned to either PA or AL arms and followed up to 42 days. Subsequent malaria episodes within a 2-years follow up period were also treated with the same ACT initially allocated. Transaminases (AST/ALT), alkaline phosphatase (ALP), total and direct bilirubin were measured at days 0 (baseline), 3, 7, 28 and on some unscheduled days if required. The proportions of non-clinical hepatic adverse events (AEs) following first and repeated treatments with PA and AL were compared within study arms. The association of these AEs with retreatment in each arm was also determined using a logistic regression model.

Results

A total of 1379 malaria episodes were included in the intention to treat analysis with 60% of all cases occurring in the AL arm. Overall, 179 non-clinical hepatic AEs were recorded in the AL arm versus 145 in the PA arm. Elevated ALT was noted in 3.05% of treated malaria episodes, elevated AST 3.34%, elevated ALP 1.81%, and elevated total and direct bilirubin in 7.90% and 7.40% respectively. Retreated participants were less likely to experience elevated ALT and AST than first episode treated participants in both arms. One case of Hy’s law condition was recorded in a first treated participant of the PA arm. Participants from the retreatment group were 76% and 84% less likely to have elevated ALT and AST, respectively, in the AL arm and 68% less likely to present elevated ALT in the PA arm. In contrast, they were almost 2 times more likely to experience elevated total bilirubin in both arms.

Conclusions

Pyronaridine-artesunate and artemether–lumefantrine showed similar hepatic safety when used repeatedly in participants with uncomplicated malaria. Pyronaridine-artesunate represents therefore a suitable alternative to the current first line anti-malarial drugs in use in endemic areas.

Trial registration Pan African Clinical Trials Registry. PACTR201105000286876

Monitoring of the Sensitivity In Vivo of Plasmodium falciparum to Artemether-Lumefantrine in Mali

In Mali, since 2007, artemether-lumefantrine has been the first choice against uncomplicated malaria. Despite its effectiveness, a rapid selection of markers of resistance to partner drugs has been documented. This work evaluated the treatment according to the World Health Organization's standard 28-day treatment method. The primary endpoint was the clinical and parasitological response corrected by a polymerase chain reaction. It was more than 99.9 percent, the proportion of patients with anemia significantly decrease compared to baseline (p < 0.001), and no serious events were recorded. Plasmodium falciparum remains sensitive to artemether-lumefantrine in Mali.

Anti-malarial efficacy and resistance monitoring of artemether-lumefantrine and dihydroartemisinin-piperaquine shows inadequate efficacy in children in Burkina Faso, 2017-2018

Background

The World Health Organization recommends regularly assessing the efficacy of artemisinin-based combination therapy (ACT), which is a critical tool in the fight against malaria. This study evaluated the efficacy of two artemisinin-based combinations recommended to treat uncomplicated Plasmodium falciparum malaria in Burkina Faso in three sites: Niangoloko, Nanoro, and Gourcy.

Methods

This was a two-arm randomized control trial of the efficacy of artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DP). Children aged 6–59 months old were monitored for 42 days. The primary outcomes of the study were uncorrected and PCR-corrected efficacies to day 28 for AL and 42 for DP. Molecular markers of resistance to artemisinin derivatives and partner drugs were also analysed.

Results

Of 720 children enrolled, 672 reached study endpoints at day 28, 333 in the AL arm and 339 in the DP arm. PCR-corrected 28-day per protocol efficacy in the AL arm was 74% (64–83%) in Nanoro, 76% (66–83%) in Gourcy, and 92% (84–96%) in Niangoloko. The PCR-corrected 42-day per protocol efficacy in the DP arm was 84% (75–89%) in Gourcy, 89% (81–94%) in Nanoro, and 97% (92–99%) in Niangoloko.

No Pfk13 mutation previously associated with artemisinin-resistance was observed. No statistically significant association was found between treatment outcome and presence of the 86Y mutation in the Pfmdr1 gene. There was also no association observed between treatment outcome and Pfpm2 or Pfmdr1 copy number variation.

Conclusion

The results of this study indicate evidence of inadequate efficacy of AL at day 28 and DP at day 42 in the same two sites. A change of first-line ACT may be warranted in Burkina Faso.

Trial Registry Pan African Clinical Trial Registry Identifier: PACTR201708002499311.

Date of registration: 8/3/2017

https://pactr.samrc.ac.za/Search.aspx

Efficacy and Safety of Pyronaridine-Artesunate for the Treatment of Uncomplicated Plasmodium falciparum and Plasmodium vivax Malaria in Myanmar

Four single-arm, prospective, clinical studies of pyronaridine–artesunate efficacy in uncomplicated Plasmodium falciparum or Plasmodium vivax malaria were conducted in Myanmar between 2017 and 2019. Eligible subjects were aged at least 6 years, with microscopically confirmed P. falciparum (n = 196) or P. vivax mono-infection (n = 206). Patients received pyronaridine–artesunate once daily for 3 days with follow-up until day 42 for P. falciparum or day 28 for P. vivax. For the primary efficacy analysis, adequate clinical and parasitological response (ACPR) in the per-protocol population at day 42 for P. falciparum malaria was 100% (88/88; 95% CI: 95.9, 100) in northern Myanmar (Kachin State and northern Shan State), and 100% (101/101; 95% CI: 96.4, 100) in southern Myanmar (Tanintharyi Region and Kayin State). Plasmodium falciparum day-3 parasite clearance was observed for 96.9% (190/196) of patients. Mutations in the P. falciparum Kelch propeller domain (K13) were detected in 39.0% (69/177) of isolates: F446I (14.7% [26/177]), R561H (13.0% [23/177]), C580Y (10.2% [18/177]), and P574L (1.1% [2/177]). For P. vivax, the day-28 ACPR was 100% (104/104; 95% CI: 96.5, 100) in northern Myanmar and 100% (97/97; 95% CI: 96.3, 100) in southern Myanmar. Across both P. vivax studies, 100% (206/206) of patients had day-3 parasite clearance. There were no adverse events. Pyronaridine–artesunate had excellent efficacy in Myanmar against P. falciparum and P. vivax and was well tolerated. This study supports the inclusion of pyronaridine–artesunate in national malaria treatment guidelines for Myanmar.

Treatment and prevention of malaria in children

Malaria disproportionately affects children younger than 5 years. Falciparum malaria is responsible for more than 200 000 child deaths per year in Africa and vivax malaria is well documented as a cause of severe anaemia and excess mortality in children in Asia and Oceania. For the treatment of malaria in children, paediatric dosing recommendations for several agents, including parenteral artesunate and dihydroartemisinin-piperaquine, have belatedly been shown to be suboptimal. Worsening antimalarial resistance in Plasmodium falciparum in the Greater Mekong Subregion threatens to undermine global efforts to control malaria. Triple antimalarial combination therapies are being evaluated to try to impede this threat. The RTS,S/AS01 vaccine gives partial protection against falciparum malaria and is being evaluated in large, pilot studies in Ghana, Malawi, and Kenya as a complementary tool to other preventive measures. Seasonal malaria chemoprevention in west Africa has resulted in declines in malaria incidence and deaths and there is interest in scaling up efforts by expanding the age range of eligible recipients. Preventing relapse in Plasmodium vivax infection with primaquine is challenging because treating children who have G6PD deficiency with primaquine can cause acute haemolytic anaemia. The safety of escalating dose regimens for primaquine is being studied to mitigate this risk.

The program and policy change framework: A new tool to measure research use in low- and middle-income countries

Organizations that fund research to address global development challenges are increasingly interested in measuring the social and economic outcomes of research. However, traditional metrics for measuring research outputs are often insufficient for capturing the outcomes targeted by international assistance organizations. To address this, the Center for Development Research (CDR), part of the U.S. Global Development Lab at the United States Agency for International Development (USAID), has designed a new tool: the Program and Policy Change (PPC) framework for tracking and quantifying the influence of research on program and policy change in international development. The framework draws on existing conceptual frameworks of evidence uptake and the literature on policy change. This article describes the design of the PPC framework and presents the results of applying the framework to two USAID research programs. The benefits of the framework include applicability across research sectors, focus on evidence-informed policy at various levels of geographical influence, and inclusion of a numeric scoring system that enables quantification of outcomes.

Pyronaridine: An update of its pharmacological activities and mechanisms of action

Pyronaridine (PYR) is an erythrocytic schizonticide with a potent antimalarial activity against multidrug-resistant Plasmodium. The drug is used in combination with artesunate for the treatment of uncomplicated P. falciparum malaria, in adults and children. The present review briefly retraces the discovery of PYR and recent antimalarial studies which has led to the approval of PYR/artesunate combination (Pyramax) by the European Medicines Agency to treat uncomplicated malaria worldwide. PYR also presents a marked antitumor activity and has revealed efficacy for the treatment of other parasitic diseases (notably Babesia and Trypanosoma infections) and to mitigate the Ebola virus propagation. On the one hand, PYR functions has an inhibitor of hemozoin (biomineral malaria pigment, by-product of hemoglobin digestion) formation, blocking the biopolymerization of β-hematin and thus facilitating the accumulation of toxic hematin into the digestive vacuole of the parasite. On the other hand, PYR is a bona fide DNA-intercalating agent and an inhibitor of DNA topoisomerase 2, leading to DNA damages and cell death. Inhibition of hematin polymerization represents the prime mechanism at the origin of the antimalarial activity, whereas anticancer effects relies essentially on the interference with DNA metabolism, as with structurally related anticancer drugs like amsacrine and quinacrine. In addition, recent studies point to an immune modulatory activity of PYR and the implication of a mitochondrial oxidative pathway. An analogy with the mechanism of action of artemisinin drugs is underlined. In brief, the biological actions of pyronaridine are recapitulated to shed light on the diverse health benefits of this unsung drug.

Different Plasmodium falciparum clearance times in two Malian villages following artesunate monotherapy

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High prevalence of residual parasitemia at day 3 post-artesunate monotherapy treatment using qPCR while no parasites were detected by microscopy at the same timepoint.

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A longer parasite clearance time observed in a Malian village.

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Artesunate treatment is still efficacious on Plasmodium falciparum in Mali.

Background

Artemisinin resistance described as increased parasite clearance time (PCT) is rare in Africa. More sensitive methods such as qPCR might better characterize the clearance phenotype in sub-Saharan Africa.

Methods

PCT is explored in Mali using light microscopy and qPCR after artesunate for uncomplicated malaria. In two villages, patients were followed for 28 days. Blood smears and spots were collected respectively for microscopy and qPCR. Parasitemia slope half-life was calculated after microscopy. Patient residual parasitemia were measured by qPCR.

Results

Uncorrected adequate clinical and parasitological responses (ACPR) observed in Faladje and Bougoula-Hameau were 78% and 92%, respectively (p = 0.01). This reached 100% for both after molecular correction.

Proportions of 24H microscopy positive patients in Faladje and Bougoula-Hameau were 97.2% and 72%, respectively (p < 0.0001).

Slope half-life was 2.8 h in Faladje vs 2H in Bougoula-Hameau (p < 0.001) and

Proportions of 72H patients with residual parasitemia were 68.5% and 40% in Faladje and Bougoula-Hameau, respectively (p = 0.003). The mean residual parasitemia was 2.9 in Faladje vs. 0.008 in Bougoula-Hameau (p = 0.002).

Although artesunate is efficacious in Mali, the longer parasite clearance time with submicroscopic parasitemia observed may represent early signs of developing P. falciparum resistance to artemisinins.

Tools to accelerate falciparum malaria elimination in Cambodia: a meeting report

Cambodia targets malaria elimination by 2025. Rapid elimination will depend on successfully identifying and clearing malaria foci linked to forests. Expanding and maintaining universal access to early diagnosis and effective treatment remains the key to malaria control and ultimately malaria elimination in the Greater Mekong Subregion (GMS) in the foreseeable future. Mass Drug Administration (MDA) holds some promise in the rapid reduction of Plasmodium falciparum infections, but requires considerable investment of resources and time to mobilize the target communities. Furthermore, the most practical drug regimen for MDA in the GMS—three rounds of DHA/piperaquine—has lost some of its efficacy. Mass screening and treatment benefits asymptomatic P. falciparum carriers by clearing chronic infections, but in its current form holds little promise for malaria elimination. Hopes that “highly sensitive” diagnostic tests would provide substantial advances in screen and treat programmes have been shown to be misplaced. To reduce the burden on P. falciparum and Plasmodium vivax infections in people working in forested areas novel approaches to the use of malaria prophylaxis in forest workers should be explored. During an October 2019 workshop in Phnom Penh researchers and policymakers reviewed evidence of acceptability, feasibility and effectiveness of interventions to target malaria foci and interrupt P. falciparum transmission and discussed operational requirements and conditions for programmatic implementation.

Factors affecting the electrocardiographic QT interval in malaria: A systematic review and meta-analysis of individual patient data

BACKGROUND

Electrocardiographic QT interval prolongation is the most widely used risk marker for ventricular arrhythmia potential and thus an important component of drug cardiotoxicity assessments. Several antimalarial medicines are associated with QT interval prolongation. However, interpretation of electrocardiographic changes is confounded by the coincidence of peak antimalarial drug concentrations with recovery from malaria. We therefore reviewed all available data to characterise the effects of malaria disease and demographic factors on the QT interval in order to improve assessment of electrocardiographic changes in the treatment and prevention of malaria.

METHODS AND FINDINGS

We conducted a systematic review and meta-analysis of individual patient data. We searched clinical bibliographic databases (last on August 21, 2017) for studies of the quinoline and structurally related antimalarials for malaria-related indications in human participants in which electrocardiograms were systematically recorded. Unpublished studies were identified by the World Health Organization (WHO) Evidence Review Group (ERG) on the Cardiotoxicity of Antimalarials. Risk of bias was assessed using the Pharmacoepidemiological Research on Outcomes of Therapeutics by a European Consortium (PROTECT) checklist for adverse drug events. Bayesian hierarchical multivariable regression with generalised additive models was used to investigate the effects of malaria and demographic factors on the pretreatment QT interval. The meta-analysis included 10,452 individuals (9,778 malaria patients, including 343 with severe disease, and 674 healthy participants) from 43 studies. 7,170 (68.6%) had fever (body temperature ≥ 37.5°C), and none developed ventricular arrhythmia after antimalarial treatment. Compared to healthy participants, patients with uncomplicated falciparum malaria had shorter QT intervals (-61.77 milliseconds; 95% credible interval [CI]: -80.71 to -42.83) and increased sensitivity of the QT interval to heart rate changes. These effects were greater in severe malaria (-110.89 milliseconds; 95% CI: -140.38 to -81.25). Body temperature was associated independently with clinically significant QT shortening of 2.80 milliseconds (95% CI: -3.17 to -2.42) per 1°C increase. Study limitations include that it was not possible to assess the effect of other factors that may affect the QT interval but are not consistently collected in malaria clinical trials.

CONCLUSIONS

Adjustment for malaria and fever-recovery-related QT lengthening is necessary to avoid misattributing malaria-disease-related QT changes to antimalarial drug effects. This would improve risk assessments of antimalarial-related cardiotoxicity in clinical research and practice. Similar adjustments may be indicated for other febrile illnesses for which QT-interval-prolonging medications are important therapeutic options.

Efficacy of Artesunate against Pseudomonas aeruginosa Biofilm Mediated by Iron

Pseudomonas aeruginosa is capable of causing a variety of chronic infections due to the formation of biofilms. Iron is essential for growth of Pseudomonas aeruginosa, and therapies that interfere with iron may help treat P. aeruginosa infections. Herein, we investigated whether artesunate, which is a type of iron-dependent drug, could influence Pseudomonas aeruginosa biofilm formation and structure, including the underlying mechanisms. Artesunate could enhance twitching motility significantly and decrease the proportion of surviving cells in Pseudomonas aeruginosa biofilms in a dose-dependent manner. Artesunate treatment also reduced biofilm thickness, diffusion in the biomass, and the content of Fe(II). However, changes in biofilm structure and ion concentration were very similar following treatment with 512 μg/ml and 1024 μg/ml artesunate. Interestingly, both biofilm structure and surviving cell fraction were recovered after iron supplementation. These results suggest that artesunate interferes with Pseudomonas aeruginosa biofilms by decreasing bacterial viability and enhancing twitching motility in an iron-independent manner.

The Impact of Malaria on Liver Enzymes: A Retrospective Cohort Study (2010-2017)

Background

It is unclear if malaria causes deranged liver enzymes. This has implications both in clinical practice and in research, particularly for antimalarial drug development.

Method

We performed a retrospective cohort study of returning travelers (n = 4548) who underwent a malaria test and had enzymes measured within 31 days in Calgary, Canada, from 2010 to 2017. Odds ratios of having an abnormal alkaline phosphatase (ALP), alanine aminotransferases (ALT), aspartate aminotransferases (AST), and total bilirubin (TB) were calculated using multivariable longitudinal analysis with binomial response.

Results

After adjusting for gender, age, and use of hepatotoxic medications, returning travelers testing positive for malaria had higher odds of having an abnormal TB (odds ratio [OR], 12.64; 95% confidence interval [CI], 6.32–25.29; P < .001) but not ALP (OR, 0.32; 95% CI, 0.09–1.10; P = .072), ALT (OR, 1.01; 95% CI, 0.54–1.89; P = .978) or AST (OR, 1.26; 95% CI, 0.22–7.37; P = .794), compared with those who tested negative. TB was most likely to be abnormal in the “early” period (day 0–day 3) but then normalized in subsequent intervals. Returning travelers with severe malaria (OR, 2.56; 95% CI, 0.99–6.62; P = .052) had borderline increased odds of having an abnormal TB, but malaria species (OR, 0.70; 95% CI, 0.24–2.05; P = .511) did not.

Conclusions

In malaria-exposed returning travelers, the TB is abnormal, especially in the early period, but no abnormalities are seen for ALT, AST, or ALP.

High cure rates and tolerability of artesunate-amodiaquine and dihydroartemisinin-piperaquine for the treatment of uncomplicated falciparum malaria in Kibaha and Kigoma, Tanzania

BACKGROUND

The Tanzanian National Malaria Control Programme (NMCP) and its partners have been implementing regular therapeutic efficacy studies (TES) to monitor the performance of different drugs used or with potential use in Tanzania. However, most of the recent TES focused on artemether-lumefantrine, which is the first-line anti-malarial for the treatment of uncomplicated falciparum malaria. Data on the performance of other artemisinin-based combinations is urgently needed to support timely review and changes of treatment guidelines in case of drug resistance to the current regimen. This study was conducted at two NMCP sentinel sites (Kibaha, Pwani and Ujiji, Kigoma) to assess the efficacy and safety of artesunate-amodiaquine (ASAQ) and dihydroartemisinin-piperaquine (DP), which are the current alternative artemisinin-based combinations in Tanzania.

METHODS

This was a single-arm prospective evaluation of the clinical and parasitological responses of ASAQ and DP for directly observed treatment of uncomplicated falciparum malaria. Children aged 6 months to 10 years and meeting the inclusion criteria were enrolled and treated with either ASAQ or DP. In each site, patients were enrolled sequentially; thus, enrolment of patients for the assessment of one artemisinin-based combination was completed before patients were recruited for assessment of the second drugs. Follow-up was done for 28 or 42 days for ASAQ and DP, respectively. The primary outcome was PCR corrected cure rates while the secondary outcome was occurrence of adverse events (AEs) or serious adverse events (SAEs).

RESULTS

Of the 724 patients screened at both sites, 333 (46.0%) were enrolled and 326 (97.9%) either completed the 28/42 days of follow-up, or attained any of the treatment outcomes. PCR uncorrected adequate clinical and parasitological response (ACPR) for DP on day 42 was 98.8% and 75.9% at Kibaha and Ujiji, respectively. After PCR correction, DP's ACPR was 100% at both sites. For ASAQ, no parasite recurrence occurred giving 100% ACPR on day 28. Only one patient in the DP arm (1.1%) from Ujiji had parasites on day 3. Of the patients recruited (n = 333), 175 (52.6%) had AEs with 223 episodes (at both sites) in the two treatment groups. There was no SAE and the commonly reported AE episodes (with > 5%) included, cough, running nose, abdominal pain, diarrhoea and fever.

CONCLUSION

Both artemisinin-based combinations had high cure rates with PCR corrected ACPR of 100%. The two drugs had adequate safety with no SAE and all AEs were mild, and not associated with the anti-malarials. Continued TES is critical to monitor the performance of nationally recommended artemisinin-based combination therapy and supporting evidence-based review of malaria treatment policies. Trial registration This study is registered at ClinicalTrials.gov, No. NCT03431714.

Efficacy and Safety of Pyronaridine-Artesunate plus Single-Dose Primaquine for Treatment of Uncomplicated Plasmodium falciparum Malaria in Eastern Cambodia

In Cambodia, multidrug-resistant Plasmodium falciparum undermines the treatment of uncomplicated malaria, and new therapeutic options are needed. Pyronaridine-artesunate has not previously been evaluated in eastern Cambodia. We conducted a single-arm, open-label, prospective study between July and December 2017 at the Koh Gnek (Mondulkiri) and Veun Sai (Rattanakiri) health centers in eastern Cambodia. Eligible patients were aged ≥7 years (females, ages 12 to 18 years, were excluded), weighing ≥20 kg, with microscopically confirmed P. falciparum monoinfection and fever. Oral pyronaridine-artesunate was administered once daily for 3 days, dosed according to body weight, plus a single dose of primaquine on day 0. Sixty patients were recruited to Koh Gnek, and 61 patients were recruited to Veun Sai. The primary outcomes, i.e., the day 42 PCR-adjusted adequate clinical and parasitological responses (ACPRs), were 98.3% (95% confidence interval [CI], 88.4 to 99.8) in Koh Gnek and 96.7% (95% CI, 87.3 to 99.2) in Veun Sai (Kaplan-Meier). In a per-protocol analysis, the proportions of patients with day 42 PCR-adjusted ACPRs were 98.3% (57/58; 95% CI, 90.8 to 100.0) at Koh Gnek and 96.7% (58/60; 95% CI, 88.5 to 99.6) at Veun Sai. The Kelch13 (C580Y) mutation was present in 70.0% (77/110) of isolates. The copy numbers were increased in 61.3% (73/119) of isolates for Pfpm2 and in 1.7% (2/119) for Pfmdr1 There was no relationship between outcome and the 50% inhibitory concentration of pyronaridine. Adverse events were consistent with malaria, and there were no serious adverse events. Pyronaridine-artesunate has high efficacy in eastern Cambodia and could be used to increase the diversity of antimalarial therapy in the region. (This study is registered in the Australian New Zealand Clinical Trials Registry [ANZCTR] under no. ACTRN12618001300268.).

Resistance to Artemisinin Combination Therapies (ACTs): Do Not Forget the Partner Drug!

Artemisinin-based combination therapies (ACTs) have become the mainstay for malaria treatment in almost all malaria endemic settings. Artemisinin derivatives are highly potent and fast acting antimalarials; but they have a short half-life and need to be combined with partner drugs with a longer half-life to clear the remaining parasites after a standard 3-day ACT regimen. When introduced, ACTs were highly efficacious and contributed to the steep decrease of malaria over the last decades. However, parasites with decreased susceptibility to artemisinins have emerged in the Greater Mekong Subregion (GMS), followed by ACTs’ failure, due to both decreased susceptibility to artemisinin and partner drug resistance. Therefore, there is an urgent need to strengthen and expand current resistance surveillance systems beyond the GMS to track the emergence or spread of artemisinin resistance. Great attention has been paid to the spread of artemisinin resistance over the last five years, since molecular markers of decreased susceptibility to artemisinin in the GMS have been discovered. However, resistance to partner drugs is critical, as ACTs can still be effective against parasites with decreased susceptibility to artemisinins, when the latter are combined with a highly efficacious partner drug. This review outlines the different mechanisms of resistance and molecular markers associated with resistance to partner drugs for the currently used ACTs. Strategies to improve surveillance and potential solutions to extend the useful therapeutic lifespan of the currently available malaria medicines are proposed.

Pyronaridine-artesunate for treating uncomplicated Plasmodium falciparum malaria

BACKGROUND

The World Health Organization (WHO) recommends artemisinin-based combination therapies (ACTs) to treat uncomplicated Plasmodium falciparum (P falciparum) malaria. Concerns about artemisinin resistance have led to global initiatives to develop new partner drugs to protect artemisinin derivatives in ACT. Pyronaridine-artesunate is a novel ACT.

OBJECTIVES

To evaluate the efficacy of pyronaridine-artesunate compared to alternative ACTs for treating people with uncomplicated P falciparum malaria, and to evaluate the safety of pyronaridine-artesunate and other pyronaridine treatments compared to alternative treatments.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; Embase; and LILACS. We also searched ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform Search Portal, and the International Standard Randomized Controlled Trial Number (ISRCTN) registry for ongoing or recently completed trials. The date of the last search was 8 May 2018.

SELECTION CRITERIA

Efficacy analysis: randomized controlled trials (RCTs) of pyronaridine-artesunate for treating uncomplicated P falciparum malaria.Safety analysis: RCTs of pyronaridine-artesunate or pyronaridine for treating P falciparum or P vivax malaria.

DATA COLLECTION AND ANALYSIS

For this update, two review authors independently re-extracted all data and assessed certainty of evidence. We meta-analysed data to calculate risk ratios (RRs) for treatment failures between comparisons, and for safety outcomes between and across comparisons.

MAIN RESULTS

We included 10 relevant studies. Seven studies were co-funded by Shin Poong Pharmaceuticals which manufactures the drug. Three studies were funded by government agencies.For efficacy analysis we identified five RCTs with 5711 participants. This included 4465 participants from 13 sites in Africa, and 1246 participants from five sites in Asia. It included 541 children aged less than five years.For polymerase chain reaction (PCR)-adjusted failures at day 28, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.59, 95% confidence interval (CI) 0.26 to 1.31; 4 RCTs, 3068 participants, low-certainty evidence), artesunate-amodiaquine (RR 0.55, 95% CI 0.11 to 2.77; 1 RCT, 1245 participants, low-certainty evidence), and mefloquine plus artesunate (RR 0.37, 95% CI 0.13 to 1.05; 1 RCT, 1117 participants, low-certainty evidence).For unadjusted failures at day 28, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.27, 95% CI 0.13 to 0.58; 4 RCTs, 3149 participants, low-certainty evidence), and probably has fewer failures compared to artesunate-amodiaquine (RR 0.49, 95% CI 0.30 to 0.81; 1 RCT, 1257 participants, moderate-certainty evidence) and mefloquine plus artesunate (RR 0.36, 95% CI 0.17 to 0.78; 1 RCT, 1120 participants, moderate-certainty evidence).For PCR-adjusted failures at day 42, pyronaridine-artesunate may make little or no difference compared to artemether-lumefantrine (RR 0.86, 95% CI 0.49 to 1.51; 4 RCTs, 2575 participants, low-certainty evidence) and artesunate-amodiaquine (RR 0.98, 95% CI 0.20 to 4.83; 1 RCT, 1091 participants, low-certainty evidence), but may have higher failures than mefloquine plus artesunate (RR 1.80, 95% CI 0.90 to 3.57; 1 RCT, 1037 participants, low-certainty evidence). Overall, pyronaridine-artesunate had a PCR-adjusted treatment failure rate of less than 5%.For unadjusted failures at day 42, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.61, 95% CI 0.46 to 0.82; 4 RCTs, 3080 participants, low-certainty evidence), may make little or no difference compared to mefloquine plus artesunate (RR 0.84, 95% CI 0.54 to 1.31; 1 RCT, 1059 participants, low-certainty evidence), and probably makes little or no difference compared to artesunate-amodiaquine (RR 0.98, 95% CI 0.78 to 1.23; 1 RCT, 1235 participants, moderate-certainty evidence).For the safety analysis of severe adverse events and liver function, we identified eight RCTs with 6614 participants comparing pyronaridine-artesunate to other antimalarials, four of which were not in the previous version of this review. A further two RCTs, comparing pyronaridine alone to other treatments, contributed to the synthesis of all adverse events.Raised alanine aminotransferase (ALT) greater than five times the upper limit of normal (> 5 x ULN) is more frequent with pyronaridine-artesunate compared to other antimalarials (RR 3.34, 95% CI 1.63 to 6.84; 8 RCTS, 6581 participants, high-certainty evidence). There is probably little or no difference for raised bilirubin > 2.5 x ULN between pyronaridine-artesunate and other antimalarials (RR 1.03, 95% CI 0.49 to 2.18; 7 RCTs, 6384 participants, moderate-certainty evidence). There was one reported case in which raised ALT occurred with raised bilirubin, meeting criteria for moderate drug-induced liver injury. No study reported severe drug-induced liver injury. Electrocardiograph (ECG) abnormalities were less common with pyronaridine-artesunate compared to other antimalarials. We identified no other safety concerns.

AUTHORS' CONCLUSIONS

Pyronaridine-artesunate was efficacious against uncomplicated P falciparum malaria, achieved a PCR-adjusted treatment failure rate of less than 5% at days 28 and 42, and may be at least as good as, or better than other marketed ACTs.Pyronaridine-artesunate increases the risk of episodes of raised ALT > 5 x ULN. This meets criteria for mild drug-induced liver injury. On one instance this was linked to raised bilirubin, indicating moderate drug-induced liver injury. No episodes of severe drug-induced liver injury were reported. The findings of this review cannot fully inform a risk-benefit assessment for an unselected population. Readers should remain aware of this uncertainty when considering use of pyronaridine-artesunate in patients with known or suspected pre-existing liver dysfunction, and when co-administering with other medications which may cause liver dysfunction.

A randomized trial of dihydroartemisinin-piperaquine versus artemether-lumefantrine for treatment of uncomplicated Plasmodium falciparum malaria in Mali

Background

Artemether–lumefantrine (AL) and artesunate–amodiaquine are first-line treatment for uncomplicated malaria in many endemic countries, including Mali. Dihydroartemisinin–piperaquine (DHA–PQ) is also an alternative first-line artemisinin-based combination therapy, but only few data are available on DHA–PQ efficacy in sub-Saharan Africa. The main aim of this study was to compare clinical efficacy of DHA–PQ versus AL, using the World Health Organization (WHO) 42-day in vivo protocol.

Methods

The efficacy of three-dose regimens of DHA–PQ was compared to AL combination in a randomized, comparative open label trial using the WHO 42-day follow-up protocol from 2013 to 2015 in Doneguebougou and Torodo, Mali. The primary endpoint was to access the PCR-corrected Adequate Clinical and Parasitological Responses at day 28.

Results

A total of 317 uncomplicated malaria patients were enrolled, with 159 in DHA–PQ arm and 158 in AL arm. The parasite positivity rate decreased from 68.4% (95% CI 60.5–75.5) on day 1 to 3.8% (95% CI 1.4–8.1) on day 2 for DHA–PQ and 79.8% (95% CI 72.3–85.7) on day 1 to 9.5% (95% CI 5.4–15.2) on day 2 for AL, (p = 0.04). There was a significant difference in the uncorrected ACPR between DHA–PQ and AL, both at 28-day and 42-day follow-up with 97.4% (95% CI 93.5–99.3) in DHA–PQ vs 84.5% (95% CI 77.8–89.8) in AL (p < 0.001) and 94.2% (95% CI 89.3–97.3) in DHA–PQ vs 73.4% (95% CI 65.7–80.2) in AL, respectively (p < 0.001). After molecular correction, there was no significant difference in ACPRc between DHA–PQ and AL, both at the 28-day and 42-day follow-up with 99.4% (95% CI 96.5–100) in DHA–PQ versus 98.1% (95% CI 94.5–99.6) in AL (p = 0.3) and 99.3% (95% CI 96.5–100) in DHA–PQ vs 97.4% (95% CI 93.5–99.3) in AL (p = 0.2). There was no significant difference between DHA–PQ and AL in QTc prolongation 12.1% vs 7%, respectively (p = 0.4).

Conclusion

The results showed that dihydroartemisinin–piperaquine and artemether–lumefantrine were clinically efficacious on Plasmodium falciparum parasites in Mali.

Therapeutic and Transmission-Blocking Efficacy of Dihydroartemisinin/Piperaquine and Chloroquine against Plasmodium vivax Malaria, Cambodia

We assessed the efficacy of standard 3-day courses of chloroquine and dihydroartemisinin/piperaquine against Plasmodium vivax malaria. Compared with chloroquine, dihydroartemisinin/piperaquine was faster in clearing asexual P. vivax parasites and blocking human-to-mosquito transmission. This drug combination was also more effective in preventing potential recurrences for >2 months.

Plasmodium falciparum gametocyte dynamics after pyronaridine-artesunate or artemether-lumefantrine treatment

BACKGROUND

Artemisinin-based combinations differ in their impact on gametocyte prevalence and density. This study assessed female and male gametocyte dynamics after treating children with uncomplicated Plasmodium falciparum malaria with either pyronaridine-artesunate (PA) or artemether-lumefantrine (AL).

METHODS

Kenyan children with uncomplicated Plasmodium falciparum malaria were included and randomly assigned to PA or AL treatment. Filter paper blood samples were collected as a source of RNA for quantitative reverse-transcription PCR (qRT-PCR) and nucleic acid sequence based amplification (QT-NASBA) to detect female gametocytes (targeting Pfs25 mRNA). Male gametocytes were detected by qRT-PCR (targeting PfMGET mRNA). Duration of gametocyte carriage, the female and male gametocyte response and the agreement between qRT-PCR and QT-NASBA were determined.

RESULTS

The mean duration of female gametocyte carriage was significantly longer for PA (4.9 days) than for AL (3.8 days) as estimated by QT-NASBA (P = 0.036), but this difference was less clear when determined by Pfs25 qRT-PCR (4.5 days for PA and 3.7 for AL, P = 0.166). qRT-PCR based female gametocyte prevalence decreased from 100% (75/75) at baseline to 6.06% (4/66) at day 14 in the AL group and from 97.7% (83/85) to 13.9% (11/79) in the PA group. Male gametocyte prevalence decreased from 41.3% (31/75) at baseline to 19.7% (13/66) at day 14 in the AL group and from 35.3% (30/85) to 22.8% (18/79) in the PA group. There was good agreement between Pfs25 qRT-PCR and QT-NASBA female gametocyte prevalence (0.85, 95% CI 0.82-0.87).

CONCLUSIONS

This study indicates that female gametocyte clearance may be slightly faster after AL compared to PA. Male gametocytes showed similar post-treatment clearance between study arms. Future studies should further address potential differences between the post-treatment transmission potential after PA compared to AL. Trial registration This study is registered at clinicaltrials.gov under NCT02411994. Registration date: 8 April 2015. https://clinicaltrials.gov/ct2/show/NCT02411994?term=pyronaridine-artesunate&cond=Malaria&cntry=KE&rank=1.

Pyronaridine-artesunate and artemether-lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in Kenyan children: a randomized controlled non-inferiority trial

Background

Pyronaridine–artesunate is a novel artemisinin-based combination therapy. The efficacy and safety of pyronaridine–artesunate were compared with artemether–lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in children.

Methods

This phase III open-label randomized controlled non-inferiority trial was conducted in Western Kenya. Children aged 6 months to ≤ 12 years with a bodyweight > 5 kg and microscopically confirmed P. falciparum malaria were randomly assigned in a 1:1 ratio to orally receive pyronaridine–artesunate or artemether–lumefantrine, dosed according to bodyweight, for 3 days.

Results

Of 197 participants, 101 received pyronaridine–artesunate and 96 received artemether–lumefantrine. The day-28 adequate clinical and parasitological response in the per-protocol population, PCR-corrected for reinfections, was 98.9% (93/94, 95% CI 94.2–99.8) for pyronaridine–artesunate and 96.4% (81/84, 95% CI 90.0–98.8) for artemether–lumefantrine. Pyronaridine–artesunate was found to be non-inferior to artemether–lumefantrine: the treatment difference was 2.5% (95% CI − 2.8 to 9.0). Adverse events occurred in 41.6% (42/101) and 34.4% (33/96) of patients in the pyronaridine–artesunate group and the artemether–lumefantrine group, respectively. No participants were found to have alanine or aspartate aminotransferase levels > 3 times the upper limit of normal.

Conclusions

Pyronaridine–artesunate was well tolerated, efficacious and non-inferior to artemether–lumefantrine for the treatment of uncomplicated P. falciparum malaria in Kenyan children. Results are in line with previous reports and inclusion of pyronaridine–artesunate in paediatric malaria treatment programmes should be considered.

This study is registered at clinicaltrials.gov under NCT02411994. Registration date: 8 April 2015. https://clinicaltrials.gov/ct2/show/NCT02411994?term=pyronaridine–artesunate&cond=Malaria&cntry=KE&rank=1

Electronic supplementary material

The online version of this article (10.1186/s12936-018-2340-3) contains supplementary material, which is available to authorized users.

Developing Research in Infectious and Tropical Diseases in Africa: The Paradigm of Senegal

Infectious diseases represent one of the greatest potential barriers to achievement of the third Sustainable Development Goals in African countries and around the world because they continue to pose major public health challenges. The surveillance of infectious diseases has recently assumed greater importance in most African countries, both because of the emergence of infectious diseases and because strains of pathogens that cause tuberculosis, malaria, cholera, dysentery, and pneumonia have developed resistance to common and inexpensive antimicrobial drugs. However, data on the pathogen-specific causes of infectious diseases are limited. Developing research in infectious and tropical diseases in Africa is urgently needed to better describe the distribution of pathogen-borne diseases and to know which pathogens actually cause fever. This research is critical for guiding treatment and policies in Africa. More effective diagnostics are also needed for these diseases, which often are misdiagnosed or diagnosed too late. A comprehensive review of this type of research is presented here.

Pyronaridine-artesunate or dihydroartemisinin-piperaquine versus current first-line therapies for repeated treatment of uncomplicated malaria: a randomised, multicentre, open-label, longitudinal, controlled, phase 3b/4 trial

BACKGROUND

Artemether-lumefantrine and artesunate-amodiaquine are used as first-line artemisinin-based combination therapies (ACTs) in west Africa. Pyronaridine-artesunate and dihydroartemisinin-piperaquine are potentially useful for diversification of ACTs in this region, but further safety and efficacy data are required on malaria retreatment.

METHODS

We did a randomised, multicentre, open-label, longitudinal, controlled phase 3b/4 clinical trial at seven tertiary centres in Burkina Faso, Guinea, and Mali. Eligible participants for first malaria episode and all retreatment episodes were adults and children aged 6 months and older with microscopically confirmed Plasmodium spp malaria (>0 to <200 000 parasites per μL of blood) and fever or history of fever in the previous 24 h. Individuals with severe or complicated malaria, an alanine aminotransferase concentration of more than twice the upper limit of normal, or a QTc greater than 450 ms were excluded. Using a randomisation list for each site, masked using sealed envelopes, participants were assigned to either pyronaridine-artesunate or dihydroartemisinin-piperaquine versus either artesunate-amodiaquine or artemether-lumefantrine. Block sizes were two or four if two treatments were allocated, and three or six if three treatments were allocated. Microscopists doing the parasitological assessments were masked to treatment allocation. All treatments were once-daily or twice-daily tablets or granules given orally and dosed by bodyweight over 3 days at the study centre. Patients were followed up as outpatients up to day 42, receiving clinical assessments on days 0, 1, 2, 3, 7, 14, 21, 28, 35, and 42. Two primary outcomes were compared for non-inferiority: the 2-year incidence rate of all microscopically confirmed, complicated and uncomplicated malaria episodes in patients in the intention-to-treat population (ITT; non-inferiority margin 20%); and adequate clinical and parasitological response (ACPR) in uncomplicated malaria across all episodes (unadjusted and PCR-adjusted for Plasmodium falciparum and unadjusted for other Plasmodium spp) in the per-protocol population on days 28 and 42 (non-inferiority margin 5%). Safety was assessed in all participants who received one dose of study drug. This study is registered at the Pan African Clinical Trials Registry (PACTR201105000286876).

FINDINGS

Between Oct 24, 2011, and Feb 1, 2016, we assigned 4710 eligible participants to the different treatment strategies: 1342 to pyronaridine-artesunate, 967 to artemether-lumefantrine, 1061 to artesunate-amodiaquine, and 1340 to dihydroartemisinin-piperaquine. The 2-year malaria incidence rate in the ITT population was non-inferior for pyronaridine-artesunate versus artemether-lumefantrine (1·77, 95% CI 1·63-1·93 vs 1·87, 1·72-2·03; rate ratio [RR] 1·05, 95% CI 0·94-1·17); and versus artesunate-amodiaquine (1·39, 95% CI 1·22-1·59 vs 1·35, 1·18-1·54; RR 0·97, 0·87-1·07). Similarly, this endpoint was non-inferior for dihydroartemisinin-piperaquine versus artemether-lumefantrine (1·16, 95% CI 1·01-1·34 vs 1·42 1·25-1·62; RR 1·22, 95% CI 1·06-1·41) and versus artesunate-amodiaquine (1·35, 1·21-1·51 vs 1·68, 1·51-1·88; RR 1·25, 1·02-1·50). For uncomplicated P falciparum malaria, PCR-adjusted ACPR was greater than 99·5% at day 28 and greater than 98·6% at day 42 for all ACTs; unadjusted ACPR was higher for pyronaridine-artesunate versus comparators at day 28 (96·9% vs 82·3% for artemether-lumefantrine and 95·6% vs 89·0% for artesunate-amodiaquine) and for dihydroartemisinin-piperaquine versus comparators (99·5% vs 81·6% for artemether-lumefantrine and 99·0% vs 89·0% for artesunate-amodiaquine). For non-falciparum species, unadjusted ACPR was greater than 98% for all study drugs at day 28 and at day 42 was greater than 83% except for artemether-lumefantrine against Plasmodium ovale (in ten [62·5%] of 16 patients) and against Plasmodium malariae (in nine [75·0%] of 12 patients). Nine deaths occurred during the study, none of which were related to the study treatment. Mostly mild transient elevations in transaminases occurred with pyronaridine-artesunate versus comparators, and mild QTcF prolongation with dihydroartemisinin-piperaquine versus comparators.

INTERPRETATION

Pyronaridine-artesunate and dihydroartemisinin-piperaquine treatment and retreatment of malaria were well tolerated with efficacy that was non-inferior to first-line ACTs. Greater access to these efficacious treatments in west Africa is justified.

FUNDING

The European and Developing Countries Clinical Trial Partnership, Medicines for Malaria Venture (Geneva, Switzerland), the UK Medical Research Council, the Swedish International Development Cooperation Agency, German Ministry for Education and Research, University Claude Bernard (Lyon, France), University of Science, Techniques and Technologies of Bamako (Bamako, Mali), the Centre National de Recherche et de Formation sur le Paludisme (Burkina Faso), Institut de Recherche en Sciences de la Santé (Bobo-Dioulasso, Burkina Faso), and Centre National de Formation et de Recherche en Santé Rurale (Republic of Guinea).

Malaria medicines to address drug resistance and support malaria elimination efforts

INTRODUCTION

Antimalarial drugs are essential weapons to fight malaria and have been used effectively since the 17^th century. However, P.falciparum resistance has been reported to almost all available antimalarial drugs, including artemisinin derivatives, raising concerns that this could jeopardize malaria elimination. Areas covered: In this article, we present a historical perspective of antimalarial drug resistance, review current evidence of resistance to available antimalarial drugs and discuss possible mitigating strategies to address this challenge. Expert commentary: The historical approach to drug resistance has been to change the national treatment policy to an alternative treatment. However, alternatives to artemisinin-based combination treatment are currently extremely limited. Innovative approaches utilizing available schizonticidal drugs such as triple combination therapies or multiple first line treatments could delay the emergence and spread of drug resistance. Transmission blocking drugs like primaquine may play a key role if given to a substantial proportion of malaria infected persons. Deploying antimalarial medicines in mass drug administration or mass screening and treatment campaigns could also contribute to containment efforts by eliminating resistant parasites in some settings. Ultimately, response to drug resistance should also include further investment in the development of new antimalarial drugs.

Artesunate inhibits proliferation and invasion of mouse hemangioendothelioma cells in vitro and of tumor growth in vivo

Artesunate has been demonstrated to be a novel potential antitumor agent in numerous studies. However, its efficacy in infantile hemangioma is unknown. The aim of the present study was to investigate the role of artesunate in the control of vascular tumor biological behavior and molecular mechanism using mouse hemangioendothelioma endothelial (EOMA) cells and a nude mouse model. Cell viability, apoptosis and invasion were determined by an MTT assay, flow cytometric analysis and Transwell invasion assay, respectively. Reverse transcription-quantitative polymerase chain reaction and western blotting were utilized to examine the expression of genes and proteins. Inoculated EOMA cells were injected into the subcutaneous tissues of nude mice to observe the effect of artesunate therapy on the vascular tumor, an effect that was similar to that of pingyangmycin (PYM). It was identified that artesunate treatment (0-600 µg/ml) inhibited cell growth in a time- and dose-dependent manner. Artesunate at 300 µg/ml significantly reduced the proliferation and invasion of EOMA cells, and significantly decreased the expression of vascular endothelial growth factor (VEGF)-A, VEGFR-1, VEGFR-2 and hypoxia inducible factor-1α over time; caspase-3 was simultaneously upregulated in vitro. Artesunate significantly inhibited tumor growth, and the curative effect was similar to that observed with PYM in vivo. It was concluded that artesunate could effectively inhibit the growth of vascular tumors, and thus could be a novel drug candidate for the treatment of infantile hemangioma.

Challenges to replace ACT as first-line drug

The spread of artemisinin and partner drug resistance through Asia requires changes in first-line therapy. The traditional modus has been the replacement of one first-line anti-malarial regimen with another. The number of anti-malarial drug candidates currently in development may have given false confidence in the expectation that resistance to artemisinin-based combination therapy (ACT) can be solved with a switch to the next anti-malarial drug regimen. A number of promising anti-malarial drug regimens did not succeed in becoming first-line drugs due to safety concerns or rapid development of resistance. Currently promising candidates for inclusion in first-line regimens, such as KAE 609, KAF 156, OZ 439, and OZ 277, have already triggered safety concerns or fears that point mutations could render the drugs inefficacious. An additional challenge for a new first-line drug is finding an appropriate partner drug. There is hope that none of the above-mentioned concerns will be substantiated in larger, upcoming trials. Meanwhile, combining already licensed anti-malarials may be a promising stop-gap measure. Practitioners in Vietnam have empirically started to add mefloquine to the current dihydroartemisinin-piperaquine. Practitioners in Africa could do worse than empirically combine already licensed co-artemether and amodiaquine when treatment with ACT no longer clears Plasmodium falciparum. Both combinations are currently undergoing trials.

Reduced ex vivo susceptibility of Plasmodium falciparum after oral artemether-lumefantrine treatment in Mali

BACKGROUND

Artemisinin-based combination therapy is the recommended first-line treatment for uncomplicated falciparum malaria worldwide. However, recent studies conducted in Mali showed an increased frequency of recurrent parasitaemia following artemether-lumefantrine (AL) treatment.

METHODS

Study samples were collected during a large WANECAM study. Ex-vivo Plasmodium falciparum sensitivity to artemether and lumefantrine was assessed using the tritiated hypoxanthine-based assay. The prevalence of molecular markers of anti-malarial drug resistance (pfcrt K76T, pfmdr1 N86Y and K13-propeller) were measured by PCR and/or sequencing.

RESULTS

Overall 61 samples were successfully analysed in ex vivo studies. Mean IC50s increased significantly between baseline and recurrent parasites for both artemether (1.6 nM vs 3.2 nM, p < 0.001) and lumefantrine (1.4 nM vs 3.4 nM, p = 0.004). Wild type Pfmdr1 N86 allele was selected after treatment (71 vs 91%, 112 of 158 vs 95 of 105, p < 0.001) but not the wild type pfcrt K76 variant (23.5 vs 24.8%, 40 of 170 vs 26 of 105, p = 0.9). Three non-synonymous K13-propeller SNPs (A522C, A578S, and G638R) were found with allele frequencies <2%.

CONCLUSION

Malian post-AL P. falciparum isolates were less susceptible to artemether and lumefantrine than baseline isolates.

New developments in anti-malarial target candidate and product profiles

A decade of discovery and development of new anti-malarial medicines has led to a renewed focus on malaria elimination and eradication. Changes in the way new anti-malarial drugs are discovered and developed have led to a dramatic increase in the number and diversity of new molecules presently in pre-clinical and early clinical development. The twin challenges faced can be summarized by multi-drug resistant malaria from the Greater Mekong Sub-region, and the need to provide simplified medicines. This review lists changes in anti-malarial target candidate and target product profiles over the last 4 years. As well as new medicines to treat disease and prevent transmission, there has been increased focus on the longer term goal of finding new medicines for chemoprotection, potentially with long-acting molecules, or parenteral formulations. Other gaps in the malaria armamentarium, such as drugs to treat severe malaria and endectocides (that kill mosquitoes which feed on people who have taken the drug), are defined here. Ultimately the elimination of malaria requires medicines that are safe and well-tolerated to be used in vulnerable populations: in pregnancy, especially the first trimester, and in those suffering from malnutrition or co-infection with other pathogens. These updates reflect the maturing of an understanding of the key challenges in producing the next generation of medicines to control, eliminate and ultimately eradicate malaria.

Comprehensive review on various strategies for antimalarial drug discovery

The resistance of malaria parasites to existing drugs carries on growing and progressively limiting our ability to manage this severe disease and finally lead to a massive global health burden. Till now, malaria control has relied upon the traditional quinoline, antifolate and artemisinin compounds. Very few new antimalarials were developed in the past 50 years. Among recent approaches, identification of novel chemotherapeutic targets, exploration of natural products with medicinal significance, covalent bitherapy having a dual mode of action into a single hybrid molecule and malaria vaccine development are explored heavily. The proper execution of these approaches and proper investment from international agencies will accelerate the discovery of drugs that provide new hope for the control or eventual eradication of this global infectious disease. This review explores various strategies for assessment and development of new antimalarial drugs. Current status and scientific value of previous approaches are systematically reviewed and new approaches provide a pragmatic forecast for future developments are introduced as well.