New drug xiflam aims to ease long COVID symptoms in small trial
NCT ID NCT06437223
First seen Jun 24, 2026 · Last updated Jun 27, 2026 · Updated 1 time
Summary
This completed Phase 2 study tested whether the oral drug Xiflam (tonabersat) can safely reduce symptoms of Long COVID compared to a placebo. Sixteen adults who had COVID-19 and then developed lasting symptoms for at least 12 weeks took part. Participants received either Xiflam or a placebo daily for 12 weeks, and researchers tracked changes in symptoms like fatigue, brain fog, and eye issues using patient-reported scales.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- Tonabersat (Xiflam)
- What this could lead to
- If successful, this could point toward a treatment to reduce the wide range of Long COVID symptoms, improving daily life for patients.
- What could go wrong
- This is a very small, early-phase trial with only 16 participants, so results may not apply to everyone. The drug may prove no better than placebo.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 2
Tests whether the treatment actually works, and watches for side effects, in a larger group.
- Participants
-
16 people
The number who actually took part.
- Started
-
Mar 2024
- Finished
-
Sep 2025
- Lead sponsor
-
A company
The lead sponsor is a pharmaceutical, biotech, or medical-device company.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
21 years and older
- Sex
-
Anyone
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: 1. Have tested positive for COVID-19 irrespective of variant or timeframe. 2. Developed signs and symptoms of the disease as described by the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO). 3. Have recovered from the infection (tested negative for COVID-19). 4. Following negative COVID-19 testing, continued to demonstrate signs/symptoms which were not pre-existing. The signs/symptoms must have persisted for 12 weeks or more. 5. Have had a persistent recurrence of a disease state (e.g., posterior uveitis, extreme fatigue etc.) that occurred following COVID-19 infection. 6. Female subjects must be: 1. Women of non-child-bearing potential, or 2. Women of child-bearing potential with a negative pregnancy test at screening, must agree to use approved methods of contraception for the duration of the study and refrain from breastfeeding for the duration of the study. 7. Males with female partners of child-bearing potential must agree to use approved methods of contraception and agree to refrain from donating sperm for the duration of the study. 8. Willing and able to give informed consent and to comply with the study procedures and assessments. Exclusion Criteria: A subject will not be eligible for inclusion in this study if any of the following exclusion criteria apply: 1. No proof of having tested positive for COVID-19 infection at any time. 2. Presence of an active ocular/systemic disease that in the opinion of the Investigator existed prior to COVID-19 infection and is not likely a LC related condition. 3. Intraocular surgery (including lens replacement surgery) within 3 months prior to randomization. 4. History of laser therapy in the macular region. 5. Any ocular or systemic condition that in the opinion of the Investigator is not LC related (e.g., pre-existing cataract) that may require surgery or medical intervention during the study period. 6. Participation in any systemic experimental treatment or any other systemic investigational new drug within 90 days prior to the start of study treatment. 7. Any screening laboratory value (hematology, serum chemistry or urinalysis) that in the opinion of the Investigator is clinically significant and not suitable for study participation. 8. Known hypersensitivity to Xiflam™ or excipients. 9. Known history of alcohol and/or drug abuse within 12 months prior to Visit 1 Screening that, in the opinion of the Investigator, may interfere with study compliance, outcome measures, safety parameters, and/or the general medical condition of the subject.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Long COVID are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Massachusetts Eye Research and Surgery Institution (MERSI)
Waltham, Massachusetts, 02451, United States
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Can slow breathing retrain the nervous system to fight long COVID?
- Can a brain zapping headset restore focus after long COVID?
- Mindfulness may offer relief for long COVID sufferers
- Can wearables decode the mystery of fatigue?
- Beetroot juice: a natural boost against long COVID fatigue?
- A One-Two punch for long COVID? supplement and therapy put to the test