A Phase 4 interventional study of Hydroxychloroquin and Placebo in Lyme Borreliosis, Nervous System, sponsored by Radboud University Medical Center. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-27.
Sponsored by Radboud University Medical Center · Phase 4, Interventional, and Treatment
The goal of this clinical trial is to learn if hydroxychloroquine works to treat long-term complaints attributed to Lyme borreliosis in adults. The main questions it aims to answer are:
Does addition of hydroxychloroquine reduce physical complaints? Researchers will compare hydroxychloroquine to a placebo (a look-alike substance that contains no drug) to see if hydroxychloroquine works to treat Lyme borreliosis.
Participants will:
Take hydroxychloroquine or a placebo two times a day during 28 days. Visit the clinic 4 times in one year for checkups and tests.
Rationale Assess other strategies for Lyme patients with vexing symptoms.
Objective Provide initial insights as to whether addition of hydroxychloroquine results in reduction of physical complaints and assessing safety and tolerability of hydroxychloroquine in these patients.
Main trial endpoints The primary endpoint is health-related quality of life, as measured by the global score of the 36-item Short-form General Health Survey (SF-36) at EOT (week 4).
Secondary trial endpoints Secondary endpoints are improvement on subscales of SF-36 (pain and physical function) at week 4, safety at week 4 and 12 and global physical health composite score of the 36-item Short-form General Health Survey (SF-36) at week 52. Of note, there are no biochemical or microbiological test available to assess cure.
Trial design This is a monocentre, randomized, double blind pilot study. Treatment last one month, with a follow up at week 52. In total the subject are participating for one year.
Trial population Patients with possible persisting B. burgdorferi s.l. infection or probable or possible post Lyme treatment Lyme borreliosis syndrome (PTLBS) will be recruited. Patients who will start antibiotic treatment can be included.
Interventions The intervention group will be treated with 28 days Doxycycline 2 x 100 mg (standard of care) combined with hydroxychloroquine 2 x 200 mg (two time a day one tablet). The control arm receives 28 days Doxycycline 2 x 100 mg (standard of care) combined with placebo 2 x 1 tablet.
Ethical considerations relating to the clinical trial including the expected benefit to the individual subject or group of patients represented by the trial subjects as well as the nature and extent of burden and risks The combination of doxycycline en hydroxychloroquine is based on expected synergy and probably enhancement of effective therapy. Its combination has been used for years in malaria and Q-fever. Its pro- and con's are well known.
The use of doxycycline and hydroxychloroquine is not associated with increased health risk.
Radboud University Medical Center is the lead sponsor of 959 studies on the registry; 134 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Doxycycline (standard of care) in combination with Hydroxychloroquine 2 x 200 mg (two times a day one tablet).
Drug: Hydroxychloroquin · Drug: Doxycycline
Doxycycline (standard of care) in combination with Placebo (two times a day one tablet).
Drug: Placebo · Drug: Doxycycline
Added to the standard of care for Lyme Disease
Also known as: Plaquenil
Standard of care in combination with placebo
Standard of care
Health-related quality of life.
Global physical health composite score of the 36-item Short-form General Health Survey (SF-36). Each item is scored on a 0 to 100 range so that the lowest and highest possible scores are 0 and 100. Higher scores indicating better health and lower scores indicating worse health or disability
Time frame: Week 4
Safety of the study medication
ATL (U/L), creat (μmol/L) and adverse events
Time frame: Week 4 and week 12
Tolerability of the study medication
Improvement on subscales of SF-36 questionnaire (Pain and physical function). Each item is scored on a 0 to 100 range so that the lowest and highest possible scores are 0 and 100. higher scores indicating better health and lower scores indicating worse health or disability.
Time frame: Week 4 and week 12
Health-related quality of life
Global physical health composite score of the 36-item Short-form General Health Survey (SF-36). Each item is scored on a 0 to 100 range so that the lowest and highest possible scores are 0 and 100. Higher scores indicating better health and lower scores indicating worse health or disability
Time frame: Week 52
No study locations are listed for this record.
Plan to share: No
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Lyme Neuroborreliosis
Radboud University Medical Center