LoiasisNCT04258670
Spontaneous Antigenemia in Loiasis
An observational study of Loiasis and Lymphatic Filariasis, run by Washington University School of Medicine at 1 site in Cameroon.
Trial summary
This prospective study will enroll and follow 60 loiasis patients with high worm burden to monitor the spontaneous release of filarial antigen in peripheral blood. This study will define the cross-reactive antigen profile of persons with spontaneous loiasis antigenemia, and determine whether it varies with time. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Loiasis, Lymphatic Filariasis
- How many people
- 86 participants
- Where
- 1 siteCameroon
- Study dates
- 23 Jan 2020to 31 May 2021
- How long will I take part?
- 1 Year
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: The study will be conducted in the Okola health district (Lékié Division, Centre Region, Cameroon), situated about 40km northeast of Yaoundé, the political capital city of Cameroon. The Okola health district is highly endemic for loiasis. Participant will be recruited among those excluded from an Onchocerciasis study due to high Mf counts >20,000/mL.
Who may be able to join
- Ability to give informed consent
- Loiasis Mf count > 20,000 Mf/mL
- Resident of study area
- No evidence of severe or systemic comorbidities
- Consent to storage of blood samples for future study
Who cannot join
- Subject plans to move from the study area during subsequent 12 months
Trial locations and contacts
1 site in 1 country.
Cameroon1 site
Centre for Research on Filariasis and other Tropical Diseases (CRFilMT)
Yaoundé
About this study
Official title: Spontaneous Antigenemia in Loiasis, A Study of the Loiasis Antigens Responsible for Cross-reactivity in the Rapid Diagnostic Test for Lymphatic Filariasis
This prospective study will enroll and follow 60 loiasis patients with high worm burden to monitor the spontaneous release of filarial antigen in peripheral blood. This study will define the cross-reactive antigen profile of persons with spontaneous loiasis antigenemia, and determine whether it varies with time.
Read the detailed description
Global efforts to eradicate lymphatic filariasis (LF) depend on rapid diagnostic tests (RDTs) that detect Wuchereria bancrofti circulating filarial antigen but these tests are unreliable in African nations where Loa loa is co-endemic because they yield false-positive results in some individuals with loiasis. The goals of this project are to define the cross-reactive antigen profile of persons with spontaneous antigenemia, how it varies over time, and to determine which L. loa antigens in cross-reactive sera best distinguish loiasis cross-reactivity from LF.
This prospective study will prospectively enroll 50 adults who presented with cross-reactive antigenemia at screening and 10 negative controls. Participants will followed for one year and tested every three months for persistence of antigenemia.
- Conditions
- Loiasis, Lymphatic Filariasis
- Being tested
- No intervention
- Keywords
- diagnostics, cross-reactivity
- Medical subject headings
- Loiasis, Elephantiasis, Filarial
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No interventionOther
Patients in these cohorts will not be given anti-filariasis therapies because these drugs are not approved for use in patients with high worm burdens (>20,000 Mf/mL)
| Study group | Role | What they receive |
|---|---|---|
| Cross-reactive loiasis | This cohort will prospectively enroll 50 adults (age 18+) with cross-reactive antigenemia based on a positive filariasis test strip (FTS) and L. loa Mf counts >20,000 Mf/mL. Receives: Other: No intervention | |
| non-cross-reactive loiasis | This cohort will prospectively enroll 10 adults (age 18+) with a negative filariasis test strip (FTS) and L. loa Mf counts >20,000 Mf/mL. |
What is being measured
The primary outcome is the main question the study is designed to answer.
prevalence of specific cross-reactive L. loa antigens at baseline
Prevalence of filariasis test strip (FTS) positive individuals at screening. Cross-reactive proteins in plasma will be identified by mass-spectrometry to identify a cross-reactive biomarker
Measured: 1 day
Secondary outcomes (1)
Recurrence of cross-reactive antigenemia
To determine if the same antigens are present at each follow up
Measured: quarterly for 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Feb 2020
- Study start23 Jan 2020
- Primary completion31 May 2021
- Study completion31 May 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for LoiasisStudies of the same condition, open and under way.
- More trials run by Washington University School of MedicineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 86 participants (actual)
- Target duration
- 1 Year
Sponsor and investigators
- Lead sponsor
- Washington University School of Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- Doris Duke Charitable Foundation, Center for Research on Filariasis and Other Tropical Diseases, Cameroon
- Responsible party
- Sponsor
- Investigators
- Philip Budge, MD, PhD, Principal investigator, Washington University School of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04258670
- Sponsor's protocol ID
- 201909003
- Status last verified
- Aug 2026
- First submitted
- 3 Feb 2020
- Last updated
- 21 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: The deidentified IPD for all primary and secondary outcomes will be made publicly available either as a supplementary file in a research publication and/or made publicly available in a data repository maintained by the Becker Biomedical Library at Washington University.
Study at a glance
From the registry record, last updated by the sponsor on 21 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Spontaneous Antigenemia in Loiasis, A Study of the Loiasis Antigens Responsible for Cross-reactivity in the Rapid Diagnostic Test for Lymphatic Filariasis
- ClinicalTrials.gov ID
- NCT04258670
- Acronym / sponsor ID
- 201909003
- Conditions
- Loiasis, Lymphatic Filariasis
- Keywords
- diagnostics, cross-reactivity
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 86 participants (actual)
- Lead sponsor
- Washington University School of MedicineUniversity, hospital or other
- Collaborators
- Doris Duke Charitable Foundation, Center for Research on Filariasis and Other Tropical Diseases, Cameroon
- Study start
- 23 Jan 2020 (actual)
- Primary completion
- 31 May 2021 (actual)
- Study completion
- 31 May 2021 (actual)
- First posted
- 6 Feb 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This prospective study will enroll and follow 60 loiasis patients with high worm burden to monitor the spontaneous release of filarial antigen in peripheral blood. This study will define the cross-reactive antigen profile of persons with spontaneous loiasis antigenemia, and determine whether it varies with time.
Detailed description
Global efforts to eradicate lymphatic filariasis (LF) depend on rapid diagnostic tests (RDTs) that detect Wuchereria bancrofti circulating filarial antigen but these tests are unreliable in African nations where Loa loa is co-endemic because they yield false-positive results in some individuals with loiasis. The goals of this project are to define the cross-reactive antigen profile of persons with spontaneous antigenemia, how it varies over time, and to determine which L. loa antigens in cross-reactive sera best distinguish loiasis cross-reactivity from LF.
This prospective study will prospectively enroll 50 adults who presented with cross-reactive antigenemia at screening and 10 negative controls. Participants will followed for one year and tested every three months for persistence of antigenemia.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 1 Year
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Cross-reactive loiasis | – | Other: No interventionThis cohort will prospectively enroll 50 adults (age 18+) with cross-reactive antigenemia based on a positive filariasis test strip (FTS) and L. loa Mf counts >20,000 Mf/mL. |
| non-cross-reactive loiasis | – | –This cohort will prospectively enroll 10 adults (age 18+) with a negative filariasis test strip (FTS) and L. loa Mf counts >20,000 Mf/mL. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study will be conducted in the Okola health district (Lékié Division, Centre Region, Cameroon), situated about 40km northeast of Yaoundé, the political capital city of Cameroon. The Okola health district is highly endemic for loiasis. Participant will be recruited among those excluded from an Onchocerciasis study due to high Mf counts >20,000/mL.
Key inclusion criteria (5 listed)
- Ability to give informed consent
- Loiasis Mf count > 20,000 Mf/mL
- Resident of study area
- No evidence of severe or systemic comorbidities
- Consent to storage of blood samples for future study
Key exclusion criteria (1 listed)
- Subject plans to move from the study area during subsequent 12 months
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No interventionPatients in these cohorts will not be given anti-filariasis therapies because these drugs are not approved for use in patients with high worm burdens (>20,000 Mf/mL) | Other | Cross-reactive loiasis |
Primary outcome
prevalence of specific cross-reactive L. loa antigens at baseline
Time frame: 1 day
Prevalence of filariasis test strip (FTS) positive individuals at screening. Cross-reactive proteins in plasma will be identified by mass-spectrometry to identify a cross-reactive biomarker
1 secondary outcome
Recurrence of cross-reactive antigenemia
Time frame: quarterly for 1 year
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Aug 2026.
- Individual participant dataSharing planned: Yes. The deidentified IPD for all primary and secondary outcomes will be made publicly available either as a supplementary file in a research publication and/or made publicly available in a data repository maintained by the Becker Biomedical Library at Washington University.
Related trials for Loiasis
Not yet recruitingPhase 3
21-day Double-blind Trial of Albendazole in Adults With Loa Loa Microfilaremia
Loiasis With Positive Blood Microfilaremia, Loiasis
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Philip Budge, MD, PhD principal investigator
Washington University School of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Loiasis and Lymphatic Filariasis, run by Washington University School of Medicine at 1 site in Cameroon.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 21 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Cameroon. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
prevalence of specific cross-reactive L. loa antigens at baseline (time frame: 1 day). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Aug 2026.