Plain English Summary
Background and study aims
Strongyloides stercoralis, commonly referred to as threadworms, is a type of parasitic worm that infects the large intestines. S. stercoralis can cause a range of gastrointestinal (gut) symptoms, including nausea, pain and diarrhoea, and long-term infections can lead to disabling complications such as anaemia, stunted growth and slow mental development. S. stercoralis infections are very common in south East Asia and affect mainly adults. At the moment the most effective drug against the infection is ivermectin (a medication used to treat a range of different parasitic infections). The aim of this study is to find out whether the medication moxidectin (a drug designed specifically to kill parasitic worms) is active against the worm in the human body.
Who can participate?
Adults with a S. stercoralis infection
What does the study involve?
Participants are randomly allocated to one of two groups. Participants in the first group receive a single dose of 8mg moxidectin. Participants in the second group receive a single dose of 200ug/kg ivermectin. At the start of the study and 21 days after treatment, participants provide stool samples so that the severity of the infection can be measured. Participants are also asked to report any unwanted side-effects from the medications 3, 24, 48 and 72 hours after treatment.
What are the possible benefits and risks of participating?
Participants will benefit from receiving a free medical examination and treatment. There are no risks of participating as the study medications have been used before and no major side effects have been reported.
Where is the study run from?
Local villages in Champasack province (Laos)
When is the study starting and how long is it expected to run for?
December 2015 to June 2016
Who is funding the study?
European Research Council (Belgium)
Who is the main contact?
Prof. Jennifer Keiser
Efficacy of moxidectin vs ivermectin against Strongyloides stercoralis infections: a randomised parallel trial
The aim of this study is to assess the first time the efficacy of oral moxidectin against S. stercoralis infection.
1. Ethical comittee of Northern and Central Switzerland, 07/12/2015, ref: EKNZ UBE-15/103
2. Ministry of Health, National Institute of Public Health, Lao People's Democratic Republic, 11/01/2016, ref: NIOPH/NECHR 075
Single-blind phase 2 randomised parallel trial
Primary study design
Secondary study design
Randomised parallel trial
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet.
Strongyloides stercoralis infection
Subjects will be randomly assigned to one of the two treatment arms:
Group 1: Participants receive a single dose of ivermectin 200 ug/kg.
Group 2: Participants receive a single dose of moxidectin 8 mg.
Follow up will be carried out 21 days after the treatment and involves the provision of two stool samples.
Primary outcome measures
Strongyloides stercoralis infection status is determined 21 days after treatment using the Baermann method in 2 stool samples.
Secondary outcome measures
1. Adverse events are measured through self-reporting 3, 24, 48 and 72 hours after treatment
2. S. stercoralis infection intensity is measured using a larval count in stool samples 21 days after treatment in relation to baseline infection intensity (LRR)
3. O. viverrini and other helminth infection status and intensity is measured using stool samples (Kato Katz method) 21 days after treatment
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Aged 18 years or over
2. Infected with S. stercoralis infection
3. Absence of major systemic illnesses
4. Written informed consent signed
Target number of participants
120 infected subjects
Participant exclusion criteria
1. Abnormal medical conditions or chronic disease
2. Negative diagnostic result for soil-transmitted helminthes infection
3. No written informed consent
4. Recent anthelminthic treatment (past 2 months)
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
National Institute of Public Health
European Research Council
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a peer reviewed journal.
Intention to publish date
Participant level data
Available on request
Results - basic reporting
2017 results in: https://www.ncbi.nlm.nih.gov/pubmed/28369530