Conceived and designed the experiments: JK JU CH SB. Performed the experiments: H. Sayed ME-G H. Sabry SA AE-W SSe-D WE-M SB. Analyzed the data: JK H. Sayed SB. Wrote the paper: JK CH JU SB.
The authors have declared that no competing interests exist.
Fascioliasis is an emerging zoonotic disease of considerable veterinary and public health importance. Triclabendazole is the only available drug for treatment. Laboratory studies have documented promising fasciocidal properties of the artemisinins (e.g., artemether).
We carried out two exploratory phase-2 trials to assess the efficacy and safety of oral artemether administered at (i) 6×80 mg over 3 consecutive days, and (ii) 3×200 mg within 24 h in 36
CRs achieved with 6×80 mg and 3×200 mg artemether were 35% and 6%, respectively. The corresponding ERRs were 63% and nil, respectively. Artemether was well tolerated. A high efficacy was observed with triclabendazole administered at 10 mg/kg (16 patients; CR: 67%, ERR: 94%) and 20 mg/kg (4 patients; CR: 75%, ERR: 96%).
Artemether, administered at malaria treatment regimens, shows no or only little effect against fascioliasis, and hence does not represent an alternative to triclabendazole. The role of artemether and other artemisinin derivatives as partner drug in combination chemotherapy remains to be elucidated.
Fascioliasis, a zoonotic disease caused by a liver fluke infection of the species
In Egypt, fascioliasis is an important clinical problem, particularly among school-aged children living in rural areas of the Nile Delta
There is a need to develop new fasciocidal drugs. Several studies have documented that the artemisinins (e.g., artemether and artesunate), which have become the most important antimalarial drugs, particularly when deployed as artemisinin-based combination therapy (ACT)
The aim of the present study was to assess the efficacy and safety of oral artemether, adhering to two different malaria treatment regimens
Ethical clearance was obtained from the Theodor Bilharz Research Institute (Giza, Egypt), the Ministry of Health and Population (Cairo, Egypt), and the Ethics Committee of Basel, Switzerland (EKBB, reference no. 54/07). The trial is registered with Current Controlled Trials (reference no. ISRCTN10372301). Written informed consent was obtained from eligible study participants or parents/legal guardians from individuals aged below 16 years.
The study was designed as an interventional, open-label, non-randomized, proof-of-concept trial, consisting of two separate single-arm studies, to evaluate the efficacy and safety of two artemether regimens in the treatment of asymptomatic
The primary end points were cure rate (CR, defined as percentage of patients who became
Paticipants who remained
Study 1 was carried out between April and July 2007 in El-Haddad El-Bahary village, Behera governorate, north-east of Delta. El-Haddad El-Bahary village is s a typical rural setting, with canals fed from the Nile River and no access to the Mediterranean. The total population in the village is 8144.
Study 2 was conducted between August 2008 and May 2010 in Abis village, located south-west of Alexandria. It comprises 10 sub-villages, with an estimated total population of 35,000. Abis village is fed by water canals drawn from the Nile River, with no access to the Mediterranean.
Artemether, formulated as 40 mg capsules (study 1) and 50 mg tablets (study 2) was purchased from Kunming Pharmaceutical Cooperation (Artemidine®; Kunming, People's Republic of China). The following two treatment schemes were investigated: (i) 6×80 mg over 3 consecutive days (study 1) and (ii) 3×200 mg within 24 h (study 2). Treatment was supervised by a physician with date and precise time of drug administration recorded. Patients were observed for 1 h to ensure retention of medication. In case of vomiting or any treatment-related adverse events, a second dose of artemether was administered.
Triclabendazole (Egaten® 250 mg tablets, scored tablets) was the product of Novartis (Basel, Switzerland). Patients who failed to become
Several weeks before conducting a parasitological baseline survey, the health directorate of Beheira (study 1) and Alexandria governorate (study 2) were informed about the objectives, procedures, and potential risks and benefits. After written informed consent was obtained, participants were asked to provide a stool sample in order to screen for the presence of
At enrollment a full clinical examination was carried out to assess participants' general health status. Exclusion criteria were: (i) age below 5 years, (ii) pregnancy, (iii) major systemic illnesses (e.g., history of chronic illness such as cancer, diabetes, hypertension, chronic heart, liver or renal disease, severe liver disease of other etiology), and (iv) recent history of anthelmintic treatment (e.g., albendazole, bithionol, dehydroemetine, mebendazole, praziquantel, and triclabendazole taken within the past 4 weeks). Patients meeting our inclusion criteria were treated with artemether, which was administered over 3 consecutive days (study 1) or within 24 h (study 2).
Adverse events were monitored on each treatment day and for 24–48 h following the final dosing. Participants were asked to report any potential drug-related signs and symptoms using a standardized questionnaire. Full clinical examinations were performed on all participants. Adverse events were graded (i.e., mild, moderate, severe, and serious) and recorded. Therapy was offered to patients presenting with adverse events, as judged by the study physician.
Five and 28 days posttreatment, blood samples were collected for clinical chemistry analyses. The final parasitological assessment started on day 28 posttreatment: stool samples were obtained from all study participants over 5 consecutive days. Patients found with
For detection and quantification of
Laboratory investigations of blood included total leukocyte count, hemoglobin, eosinophilic count, alanine transpeptidase (ALT), aspartate transpeptidase (AST), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), total serum bilirubin, blood urea, and serum creatinine. The blood specimens were collected into gel serum tubes (for clinical chemistry variables) and EDTA tubes (for hematology variables). Blood specimens collected into gel tubes were centrifuged at 1800–2000
Data were entered using EpiData version 6.04 (Epidata Association; Odense, Denmark). CR was calculated as proportion of individuals excreting
Of 584 villagers and 51 school-aged children screened in El-Haddad El-Bahary village (study 1), 22 individuals were found
Treatment | ||||
Characteristics | Artemether(6×80 mg) | Artemether(3×200 mg) | Triclabendazole(10 mg/kg) | Triclabendazole(20 mg/kg) |
No. of patients treated | 20 | 17 | 16 | 4 |
Males/females | 10/10 | 7/10 | 6/10 | 2/2 |
Mean (SD) age, years | 24.4 (21.5) | 13.9 (5.8) | 14.4 (5.8) | 16.3 (2.5) |
Mean (SD) weight, kg | 43.9 (23.1) | 49.5 (24.4) | 55.4 (26.2) | 66.3 (19.8) |
Range of actual total dose (mean), mg/kg | 6–26.7 (14.4) | 8.3–31.6 (15.8) | n.d. | n.d. |
n.d., not determined; SD, standard deviation.
In the second study, 631 individuals were examined and 19
The baseline GM
Treatment |
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Infection intensity | No. of patients treated | No. of patients cured (%) | Pre-treatment GM |
Post-treatment GM |
ERR (%) | No. of patients treated | No. of patients cured (%) | ERR (%) | |
Study 1(6×80 mg artemether) | All infections | 20 |
7 (35) |
28.3 | 10.4 | 63 |
5 | 3 (60) | 59 |
1–99 EPG | 13 | 7 (54) |
12.6 | 4.2 | 67 | ||||
≥100 EPG | 6 | 0 | 161.0 | 72.7 | 55 | ||||
Study 2(3×200 mg artemether) | All infections | 17 | 1 (6) | 29.1 | 32.0 | 0 | 5 | 3 (60) | n.d. |
1–99 EPG | 13 | 1 (8) | 18.8 | 21.7 | 0 | ||||
≥100 EPG | 4 | 0 | 119.6 | 113.0 | 5.5 | ||||
Follow-up: triclabendazole (10 mg/kg) | 16 | 11 (69) |
32.0 | 2.0 | 94 |
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Follow-up: triclabendazole (20 mg/kg, split dose) | 4 | 3 (75) | 39.6 | 1.5 | 96 |
EPG, eggs per gram of stool; ERR, egg reduction rate; GM, geometric mean; n.d., not determined.
*One patient was diagnosed positive with MIF only, hence no quantitative egg count is available at baseline.
**CR significantly different (P<0.05) from study 2 (3×200 mg artemether).
***ERR highly significantly different (P<0.001) from study 2 (3×200 mg artemether).
Data from all patients were included in the analysis, as no patient was lost to follow-up (per-protocol analysis). CRs achieved with 6×80 mg and 3×200 mg artemether were 35% and 6%, respectively (
Study was carried out in Egypt and
In each of the two studies, five patients were co-infected with
Sixteen patients who were still found
There were no noteworthy effects of artemether on the liver enzymes and renal function parameters, with the exception of a statistically significant increase in GGT 5 days after the final dosing of artemether (6×80 mg) (
Parameter | Reference range | Study 1 (6×80 mg artemether) | Study 2 (3×200 mg artemether) | ||||
Day of analysis | Day of analysis | ||||||
Pretreatment day 0 (mean ± SD) | Post-treatment day 7 (mean ± SD) | Post-treatment day 28 (mean ± SD) | Pretreatment day 0 (mean ± SD) | Posttreatment day 5 (mean ± SD) | Posttreatment day 28 (mean ± SD) | ||
Alkaline phosphatase (ALP) (IU/L) | 30–120 | 162.1 (17.3) | 163.4 (16.1) | 161.1 (17.1) | 65.8 (30.2) | 63.8 (28.8) | 61.3 (29.8) |
Alanine transaminase (ALT) (IU/L) | 9–60 | 4.8 (0.6) | 4.1 (0.4) | 5.2 (0.5) | 3.4 (4.6) | 3.2 (2.2) | 2.0 (1.0) |
Aspartate transaminase (AST) (IU/L) | 10–40 | 10.0 (0.3) | 10.2 (0.4) | 13.2 (2.1) | 3.4 (2.7) | 3.8 (4.3) | 3.3 (2.5) |
Gamma glutamyl transpeptidase (GGT) (IU/L) | 0–51 | 10.7 (1.3) | 12.2 (1.3) |
10.8 (1.4) |
8.0 (2.4) | 7.3 (1.7) | 6.4 (2.3) |
Bilirubin (mg/dl) | 0.2–1.2 | 0.4 (0.1) | 0.4 (0.1) | 0.3 (0.03) | 0.4 (0.1) | 0.4 (0.1) | 0.4 (0.1) |
Urea (mg/dl) | 12–48 | 29.0 (2.0) | 29.7 (1.3) | 28.8 (1.1) | 35.2 (5.6) | 35.2 (5.6) | 34.6 (6.0) |
Creatinine (mg/dl) | 0.6–1.3 | 0.7 (0.03) | 0.8 (0.04) | 0.7 (0.03) | 0.9 (0.3) | 0.9 (0.2) | 0.8 (0.1) |
Eosinophils (%) | 0–6 | 3.3 (0.4) | 4.0 (0.4) | 3.4 (0.4) | 3.4 (1.9) | 4.3 (2.8) | 4.3 (2.8) |
Hemoglobin (g/dl) | 11.5–17.5 | 10.4 (0.3) | 10.45 (0.3) | 11.17 (0.2) |
13.6 (1.2) | 13.4 (1.4) | 13.0 (1.1) |
Total leucocytes (mm3) | 3900–10,000 | 6300 (179) | 6253 (181) | 6028 (195) | 6010 (976) | 6055 (1110) | 6421 (874) |
*Statistically significant difference from baseline (p<0.05).
**Statistically significant difference between first and second follow-up survey.
The comparison between pre- and posttreatment values of liver and renal function and hematological parameters showed no significant differences following administration of triclabendazole (10 and 20 mg/kg) (
Parameter | Reference range | 10 mg/kg triclabendazole (n = 16) | 20 mg/kg triclabendazole (n = 4) | ||||
Day of analysis | Day of analysis | ||||||
Pretreatment day 0 (mean ± SD) | Post-treatment day 5 (mean ± SD) | Post-treatment day 28 (mean ± SD) | Pretreatment day 0 (mean ± SD) | Post-treatment day 5 (mean ± SD) | Post-treatment day 28 (mean ± SD) | ||
Alkaline phosphatase (ALP) (IU/l) | 30–120 | 133.7 (38.8) | 137.3 (39.9) | 135.8 (37.7) | 111.0 (65.1) | 106.4 (59.2) | 99.5 (32.2) |
Alanine transaminase (ALT) (IU/l) | 9–60 | 10.9 (2.3) | 16.0 (11.4) | 11.9 (2.5) | 18.3 (3.2) | 19.3 (8.1) | 20.5 (9.3) |
Aspartate transaminase (AST) (IU/l) | 10–40 | 10.6 (3.9) | 19.6 (23.2) | 13.1 (3.0) | 23.5 (10.4) | 29.3 (13.7) | 29.3 (8.7) |
Gamma glutamyl transpeptidase (GGT) (IU/l) | 0–51 | 7.0 (1.4) | 8.3 (2.6) | 7.7 (1.8) | 7.2 (1.1) | 9.4 (3.3) | 9.4 (3.3) |
Bilirubin (mg/dl) | 0.2–1.2 | 0.6 (0.2) | 0.4 (0.3) |
0.6 (0.2) |
0.4 (0.1) | 0.6 (0.3) | 0.6 (0.1) |
Urea (mg/dl) | 12–48 | 37.9 (11–0) | 35.2 (12.6) | 34.7 (6.6) | 23.8 (2.0) | 18.1 (6.3) | 22.2 (2.7) |
Creatinine (mg/dl) | 0.6–1.3 | 0.8 (0.2) | 0.7 (0.2) | 0.8 (0.1) | 0.9 (0.3) | 1.1 (0.4) | 0.9 (0.2) |
Eosinophils (%) | 0–6 | 4.5 (2.5) | 3.3 (1.5) | 3.5 (1.2) | 3.8 (1.0) | 3.5 (1.0) | 4.0 (0.8) |
Hemoglobin (g/dl) | 11.5–17.5 | 12.8 (1.8) | 11.3 (1.1) |
12.5 (1.3) |
13.5 (0.6) | 13.3 (0.8) | 12.9 (0.6) |
Total leucocytes (mm3) | 3900–10,000 | 6356 (951) | 5950 (1074) | 6707 (918) | 5300 (902) | 5900 (1320) | 6350 (661) |
*Statistically significant difference from baseline (p<0.05).
**Statistically significant difference between first and second follow-up survey.
Both artemether regimens were well tolerated and no participant required special medical follow-up. As summarized in
Treatment | Adverse event | Grading | No. of adverse events (%) | ||||
Study 1 (6×80 mg artemether) (n = 20) |
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Abdominal pain | Mild | 0 | 6 (30) | 1 (5) | 7 (35) | 5 (25) | |
Moderate | 0 | 1 (5) | 0 | 0 | 0 | ||
Fatigue | Mild | 0 | 4 (20) | 1 (5) | 1 (5) | 0 | |
Moderate | 0 | 0 | 0 | 0 | 0 | ||
Headache | Mild | 0 | 1 (5) | 1 (5) | 3 (15) | 0 | |
Moderate | 0 | 0 | 0 | 0 | 0 | ||
Diarrhea | Mild | 0 | 0 | 5 (25) | 5 (25) | 0 | |
Moderate | 0 | 1 (5) | 0 | 0 | 0 | ||
Nausea | Mild | 0 | 0 | 0 | 0 | 0 | |
Moderate | 0 | 0 | 0 | 0 | 0 | ||
Vomiting | Mild | 1 (5) | 1 (5) | 0 | 0 | 0 | |
Moderate | 0 | 0 | 0 | 0 | 0 | ||
Study 2 (3×200 mg artemether) (n = 17) |
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Abdominal pain | Mild | 1 (5) | 1 (5) | 4 (21) | 6 (32) | ||
Fatigue | Mild | 0 | 0 | 0 | 4 (21) | ||
Headache | Mild | 3 (16) | 0 | 3 (16) | 13 (69) | ||
Diarrhea | Mild | 0 | 0 | 1 (5) | 2 (11) | ||
Nausea | Mild | 0 | 0 | 0 | 3 (16) | ||
Vomiting | Mild | 0 | 0 | 0 | 4 (21) | ||
Fever | Mild | 0 | 0 | 0 | 6 (32) | ||
Dizziness | Mild | 3 (16) | 0 | 3 (16) | 1 (5) |
Abdominal pain was more often observed after treatment with triclabendazole (
Treatment | Adverse event | Grading | No. of adverse events (%) | ||
Examination point (hours posttreatment) | |||||
24 | 48 | 72 | |||
Triclabendazole (10 mg/kg) (n = 16) | Abdominal pain | Mild | 0 | 8 (50) | 8 (50) |
Moderate | 0 | 1 (6.3) | 3 (18.8) | ||
Fatigue | Mild | 0 | 0 | 1 (6.3) | |
Moderate | 0 | 0 | 0 | ||
Headache | Mild | 0 | 5 (31.3) | 5 (31.3) | |
Moderate | 0 | 0 | 1 (6.3) | ||
Diarrhea | Mild | 0 | 0 | 4 (25) | |
Moderate | 0 | 0 | 1 (6.3) | ||
Nausea | Mild | 0 | 0 | 0 | |
Moderate | 0 | 0 | 0 | ||
Vomiting | Mild | 0 | 2 (12.5) | 2 (12.5) | |
Moderate | 0 | 0 | 0 | ||
Fever | Mild | 0 | 0 | 1 (6.3) | |
Moderate | 0 | 2 (12.5) | 0 | ||
Dizziness | Mild | 0 | 10 (62.5) | 4 (25) | |
Moderate | 0 | 0 | 0 | ||
Triclabendazole (20 mg/kg) (n = 4) | Abdominal pain | Mild | 0 | 4 | 2 |
Moderate | 0 | 0 | 0 | ||
Fatigue | Mild | 0 | 2 (50) | 0 | |
Moderate | 0 | 0 | 0 | ||
Headache | Mild | 3 (75) | 2 (50) | 1 (25) | |
Moderate | 0 | 0 | 1 (25) | ||
Diarrhea | Mild | 0 | 1 (25) | 1 (25) | |
Moderate | 0 | 0 | 0 | ||
Nausea | Mild | 1 (25) | 3 (75) | 0 | |
Moderate | 0 | 0 | 0 | ||
Vomiting | Mild | 0 | 1 (25) | 1 (25) | |
Moderate | 0 | 0 | 0 | ||
Fever | Mild | 1 (25) | 1 (25) | 0 | |
Moderate | 0 | 0 | 1 (25) | ||
Dizziness | Mild | 2 (50) | 2 (50) | 0 | |
Moderate | 0 | 0 | 0 |
While the veterinary importance of fascioliasis cannot be overemphasized, this zoonotic disease is also of considerable and growing public health importance, yet it often remains neglected. A major challenge is that treatment is restricted to a single drug, i.e., triclabendazole, which is registered for human use only in Ecuador, Egypt, France, and Venezuela
Our study failed to extend promising findings obtained with the artemisinins in rats experimentally, and sheep naturally, infected with
In the present study, five participants in each of the two studies were co-infected with
CRs of 69% and 75% were observed in patients treated with triclabendazole at 10 mg/kg and 20 mg/kg, respectively. The observed efficacy is slightly lower than a calculated overall CR of 83% following 10 mg/kg and reported CRs ranging from 93 to 100% following a double dose of triclabendazole
In conclusion, significantly higher CRs and ERRs were observed with triclabendazole when compared to artemether, the latter administered following two malaria treatment schedules. Hence, triclabendazole remains the drug of choice against fascioliasis. In view of threatening triclabendazole resistance development, concerted efforts are required, including structure-activity relationships with the synthetic peroxides in
CONSORT Checklist.
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Trial Protocol.
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