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Completed

NCT Number: NCT05999435

Study of LAU-7b for the Treatment of Long COVID in Adults

ESSOR is a double-blind, placebo-controlled study of the orally-administered antiviral and inflammation-controlling LAU-7b for the treatment of adults with Long COVID and moderate to severe symptoms.

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Key information

Conditions

Long COVID COVID-19 Chronic Disease Coronaviridae Infections Coronavirus Infections Disease Attributes Infections Lung Diseases Nidovirales Infections Pathologic Processes Pathological Conditions, Signs and Symptoms Pneumonia Pneumonia, Viral Post-Acute COVID-19 Syndrome Post-Infectious Disorders RNA Virus Infections Respiratory Tract Diseases Respiratory Tract Infections Virus Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2 / Phase 3

Primary location

CIUSS du Saguenay-Lac-St-Jean - Hôpital Chicoutimi, Chicoutimi, Quebec, Canada

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About this study

ESSOR is a multicenter, randomized, double-blind, placebo-controlled Phase 2/3 study of LAU-7b for the treatment of Long COVID in non-hospitalized adults with moderate to severe Long COVID symptoms.

The goal of the study is to evaluate the efficacy of LAU-7b therapy + stable symptomatic standard-of-care relative to placebo + stable symptomatic standard-of-care at reducing the overall Long COVID burden by improving multiple dimensions of quality-of-life and alleviating the symptoms.

This study is a logical extension of investigating LAU-7b as a potential therapeutic against various phases of COVID-19.

LAU-7b is therefore being proposed as a potential disease-modifying medication for the treatment of Long COVID.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Subjects must be 18 years and older, of either gender, and able to give informed consent;
  • Subjects diagnosed with Long COVID and exhibiting persisting, relapsing or new Long COVID symptom(s) at least 12 weeks beyond the start (test positivity or symptom onset) of the causative COVID-19 infection;
  • At least one of the Long COVID symptoms must be from the core list of Long COVID symptoms, and be present for a minimum of 2 weeks prior to screening and of moderate or severe intensity as per the 4-level Likert severity scale (0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms);
  • If female, must be either post-menopausal (one year or greater without menses), surgically sterile, or, for female subjects of child-bearing potential who are capable of conception, must be: practicing a highly effective method of birth control (acceptable methods include intrauterine device, complete abstinence, spermicide + barrier, male partner surgical sterilization, or hormonal contraception) during the study treatment intake and through 30 days after the last dose of the study medication. Periodical abstinence is not classified as an effective method of birth control. A pregnancy test for female subjects of child-bearing potential must be negative at the Screening Visit;
  • Subjects deemed capable of adequate compliance including attending scheduled follow-up calls/visits for the duration of the study, have internet access and able to read and answer questionnaires on electronic Patient Reported Outcomes platform (ePRO) or paper;
  • Screening laboratory test and vital signs results within ranges compatible with the subject's health condition, as per investigator's judgement. See also the last exclusion for certain liver function tests;
  • Subjects deemed capable of swallowing the study treatment capsules

Exclusion criteria

  • Subject is currently hospitalized (any reason);
  • Pregnancy or breastfeeding;
  • Any COVID vaccination within 4 weeks of screening or planned during study participation;
  • Presence of any health condition judged by the investigator to be directly causing one or more of the most common Long COVID symptoms;
  • Health condition deemed to possibly interfere with the study endpoints and/or the safety of the subjects. For example, the following conditions should be considered contraindicated for participation in the study. In case of doubt, the Investigator should consult with the Sponsor's medical representative:
  • Febrile neutropenia;
  • Fibromyalgia deemed to interfere with generalized pain measurements;
  • Presence of end-stage cancer (palliative care).
  • Presence or suspicion of drug or alcohol abuse, as judged by the Investigator;
  • Known history of a severe allergy or sensitivity to retinoids, or with known allergies to excipients in the oral capsule formulation proposed to be used in the study;
  • Participation in another interventional drug, alimentary supplement, psychological or device...etc. clinical trial within 30 days (or a minimum of 5 elimination half-lives for drugs) prior to screening, except ongoing participation in non-interventional studies;
  • Presence of total bilirubin >1.5 x Upper Limit of Normal (in the absence of demonstrated Gilbert's syndrome), alanine aminotransferase and/or aspartate aminotransferase > 2.5 x Upper Limit of Normal (unless there are clinical evidences of hepatic steatosis).

Treatment and study plan

LAU-7b for 3 cycles

Drug

Three cycles of 14 days of once-a-day intake of LAU-7b, each followed by a treatment intake pause of 14 days.

Other names: fenretinide

LAU-7b for 1 cycle, then placebo

Drug

One cycle of 14 days of once-a-day intake of LAU-7b followed by two cycles of 14 days of placebo administered similarly, each followed by a treatment intake pause of 14 days.

Other names: fenretinide

Placebo for 3 cycles

Other

Three cycles of 14 days of once-a-day intake of placebo, each followed by a treatment intake pause of 14 days

Other names: sugar pill

Primary outcomes

  1. Change From Baseline in Physical Component Summary (PCS) of the Medical Outcomes Study Short-Form-36 (SF-36) at Week 12

    Time frame: Week 0 and 12

    The SF-36 questionnaire consists of 36 items grouped in eight health domains, vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, and mental health, that can be aggregated to two summary scales, physical component summary (PCS ) and mental component summary (MCS). The PCS summarizes the physical status and constitutes the primary outcome variable. Each health domain score consists of the sum scores of the assigned questions. Scores are weighted and transformed into a scale ranging from 0 (greatest possible health restrictions, ie, severe disability) to 100 (no health restrictions). A higher score means a better physical status. The calculation process for the PCS has been previously described by Taft et al. 2001.

Secondary outcomes

  1. Safety of LAU-7b, Overview

    Time frame: From Week 0 to Week 12

    Number of participants with adverse events. The safety was assessed through the monitoring of adverse events including laboratory test abnormalities, serious adverse events and adverse events leading to study treatment discontinuation. Treatment-emergent adverse event is defined as any adverse event with onset date on or after the first dose of study drug and on or before the Week 12 in person follow-up or until early termination or death, whichever occurred first.

  2. Patient Global Impression of Change (PGI-C)

    Time frame: Weeks 4, 8 and 12

    The PGI-C is a single item questionnaire that asks: "Overall, how would you rate the change in your ability to perform usual daily activities since you started the study?".

    These are the 7-point scale options: 1) "very much better", 2) "much better", 3) "minimally better", 4) "no change", 5) "minimally worse", 6) "much worse", or 7) "very much worse".

    Higher scores indicate a change for the worse and lower scores indicate a change for the better.

  3. Proportion of Participants With Marked Improvement in PGI-C

    Time frame: Weeks 4, 8 and 12

    Marked improvement includes "Very much improved" and Much improved". The PGI-C is a single item questionnaire that asks: "Overall, how would you rate the change in your ability to perform usual daily activities since you started the study?".

    These are the 7-point scale options: 1) "very much better", 2) "much better", 3) "minimally better", 4) "no change", 5) "minimally worse", 6) "much worse", or 7) "very much worse".

    Higher scores indicate a change for the worse and lower scores indicate a change for the better.

  4. Change From Baseline in the Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-F) Scale

    Time frame: Weeks 0, 4, 8 and 12

    This instrument was developed to characterize fatigue, in cancer and used in other conditions with a phenotype of fatigue. It is a 13-item measure that assesses self-reported fatigue and its impact upon daily activities and function. The recall period is 7 days and the response scale employs a 5-point Likert-type scale. The final total score is the sum of the responses for all 13 items and can range from 0 to 52. A higher score means less fatigue.

  5. Change From Baseline in the DePaul Post-Exertional Malaise Questionnaire (DPEMQ)

    Time frame: Weeks 0 and 12

    This instrument was developed to characterize and evaluate the debilitation caused by a physical exertion, whether a usual daily activity or a leisure activity. It is a 10-item questionnaire that assess both the nature of post-exertional malaise (PEM) and duration of symptom. In this study, the presence or not of PEM (based on frequency and severity of 5 PEM items) is determined by the questionnaire. The endpoint of the study is the proportion of participants with PEM at baseline and Week 12, compared between treatment groups.

  6. Change From Baseline in Physical Component Summary (PCS) of the Medical Outcomes Study Short-Form-36 (SF-36) at Weeks 4 and 8

    Time frame: Weeks 0, 4 and 8

    The SF-36 questionnaire consists of 36 items grouped in eight health domains, vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, and mental health, that can be aggregated to two summary scales, physical component summary (PCS ) and mental component summary (MCS). The PCS summarizes the physical status and constitutes the primary outcome variable. Each health domain score consists of the sum scores of the assigned questions. Scores are weighted and transformed into a scale ranging from 0 (greatest possible health restrictions, ie, severe disability) to 100 (no health restrictions). A higher score means a better physical status. The calculation process for the PCS has been previously described by Taft et al. 2001. The analysis is performed jointly with the primary outcome measure (Week 12). A positive change from baseline value means improvement, negative value means worsening.

  7. Change From Baseline in the Other Aspects (Domain Scales) Than the PCS of the Medical Outcomes Study Short-Form-36 (SF-36)

    Time frame: Weeks 0, 4, 8 and 12

    The SF-36 questionnaire consists of 36 items grouped in eight health domains, vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, and mental health, that can be aggregated to two summary scales, physical component summary (PCS ) and mental component summary (MCS). Scores are weighted and transformed into a scale ranging from 0 (greatest possible health restrictions, ie, severe disability) to 100 (no health restrictions). A higher score means a better outcome. The study endpoint is the change from baseline in score, a positive change from baseline value means improvement and a negative value means worsening outcome. For sake of conciseness, only Week 12 comparisons are presented.

  8. Proportion of Subjects Who Judge to Have Regained Their Daily Usual Activity Level of Pre-causative-infection.

    Time frame: From Week 0 through Weeks 4, 8 and 12

    This will be assessed by a single question with either yes or no as answer: "Do you judge that you have regained the daily usual activity level you had prior to being infected by COVID-19 back in Month xxxx? By daily usual activity we mean work, leisure, physical exercise...etc."

  9. Proportion of Subjects Achieving >=25% (>=50% and >=75% Presented Separately) Improvement in the Sum of Individual Core Long COVID Symptom Severity as Evaluated by a Standard 4-level Likert Scale.

    Time frame: Weeks 4, 8 and 12

    The Core (most common) Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (most commonly known as brain fog or memory fog) and mental health symptoms.

    Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom.

    0 and 1 are deemed not burdensome, 2 and 3 are burdensome. A sum of the burdensome category is calculated for each visit and is the endpoint being evaluated for improvement since burdensome symptoms are those with highest impact on daily usual activity level.

  10. Proportion of Subjects Achieving >=50% (>=25% and >=75% Presented Separately) Improvement in the Sum of Individual Core Long COVID Symptom Severity as Evaluated by a Standard 4-level Likert Scale.

    Time frame: Weeks 4, 8 and 12

    The Core (most common) Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (most commonly known as brain fog or memory fog) and mental health symptoms.

    Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom.

    0 and 1 are deemed not burdensome, 2 and 3 are burdensome. A sum of the burdensome category is calculated for each visit and is the endpoint being evaluated for improvement since burdensome symptoms are those with highest impact on daily usual activity level.

  11. Proportion of Subjects Achieving >=75% (>=25% and >=50% Presented Separately) Improvement in the Sum of Individual Core Long COVID Symptom Severity as Evaluated by a Standard 4-level Likert Scale.

    Time frame: Weeks 4, 8 and 12

    The Core (most common) Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (most commonly known as brain fog or memory fog) and mental health symptoms.

    Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom.

    0 and 1 are deemed not burdensome, 2 and 3 are burdensome. A sum of the burdensome category is calculated for each visit and is the endpoint being evaluated for improvement since burdensome symptoms are those with highest impact on daily usual activity level.

  12. Change From Baseline in the EuroQol-5 Dimensions -5 Levels (EQ-5D-5L) Score

    Time frame: Weeks 0, 4, 8 and 12

    EQ-5D-5L is a self-report survey that measures quality of life across 5 domains: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension is scored on a 5-level severity ranking that ranges from no problems (Level 1); slight; moderate; severe; and extreme problems (Level 5). Higher values indicate worse outcomes, while lower indicate better outcomes. The subscales are combined to compute a total score index, adjusted for a standard value of general population in a country/region and averaged to produce the mean and SD. The Summary index value range is from 0 to 1, where 1 is considered the best possible health and 0 is the worst possible health. For the change in score, a positive number indicates that the scores improved from baseline.

  13. Proportion of Subjects With Relief of at Least One Core Burdensome Long COVID Symptom for a Minimum of 2 Weeks.

    Time frame: From Week 0 to Week 12

    The core Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (most commonly known as brain fog or memory fog) and mental health symptoms.

    Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom.

    0 and 1 are deemed not burdensome, 2 and 3 are burdensome.

    Relief means a reduction of severity from moderate to none, or severe to mild/none (≥2-point Likert score change)

  14. Time to Relief of the First Core Burdensome Long COVID Symptom for a Minimum of 2 Weeks, Among Those Symptoms Present at Baseline.

    Time frame: From Week 0 to Week 12

    The core Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (brain fog or memory fog) and mental health symptoms. Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom. 0 and 1 are deemed not burdensome, 2 and 3 are burdensome. This will be assessed through periodic inventory of the core Long COVID symptoms, performed at each visit. Relief means a reduction of severity from moderate to none, or severe to mild/none (≥2-point Likert score change). A longer time is worse than a short time to resolution.

  15. Proportion of Subjects With a Sustained Clinical Recovery, Meaning a Relief of All Core Long COVID Symptoms.

    Time frame: Weeks 4, 8 and 12

    The core Long COVID symptoms are: fatigue, trouble sleeping, shortness of breath, general pain and discomfort, cognitive problems (most commonly known as brain fog or memory fog) and mental health symptoms.

    Each symptom is rated as: 0=No symptom, 1=Mild symptom (no interference with daily activities), 2=Moderate symptom (interfere and may limit daily activities), and 3=Severe symptom (strong interference preventing daily activities. The higher the rating is, worse is the symptom.

    0 and 1 are deemed not burdensome, 2 and 3 are burdensome.

    This will be assessed through periodic inventory of the core Long COVID symptoms, performed at each visit. Relief means a reduction of severity from moderate to none, or severe to mild/none (≥2-point Likert score change). A higher proportion is better than a lower proportion.

  16. Change From Baseline in the Total Number of Long COVID Symptoms (Core and Non-core).

    Time frame: Weeks 0, 4, 8 and 12, as well as the longer term visit at Week 24

    This will be assessed through periodic inventory of all the Long COVID symptoms, performed at each visit, relative to the baseline inventory. A lower total number is better than a higher total number.

  17. Proportion of Subjects With Long COVID-related Unplanned Medical Visits

    Time frame: From Week 0 to Week 12

    This will be assessed by probing the subjects at each visit. Long COVID-related unplanned medical visits includes visits to practitioner's office, urgent care visits, emergency room <24h, or hospitalization >24 hours.

    A higher proportion is worse than a lower proportion

  18. Proportion of Subjects Deceased From Any Cause Through Week 12.

    Time frame: From Week 0 to Week 12

    This will be assessed by probing the subjects at each visit, including caretakers or relatives if the subjects cannot be reached at a given visit.

    A higher proportion is worse than a lower proportion

  19. Proportion of Subjects With Significant Cardiovascular Events

    Time frame: From Week 0 to Week 12 and including up to the long-term follow-up at Week 24

    A significant cardiovascular event is one that results in at least an acute care visit, a hospitalization or an event-related death.

    A higher proportion is worse than a lower proportion

Other outcomes

  1. Health and Survival Follow-up (Week 24), Long COVID Symptom Count

    Time frame: Week 24

    This is now presented as part of Outcome #17. Initially planned to be separate from the reporting and analysis of the Week 12 outcomes, a longer term contact was made at Week 24 to assess the following: Presence or not of Long COVID symptoms (total number of Long COVID symptoms).

  2. Health and Survival Follow-up (Week 24), Significant Cardiovascular Events

    Time frame: Week 24

    General health check-up: Assess significant cardiovascular events (one that results in at least an acute care visit, a hospitalization or an event-related death) and survival.

  3. Baseline Values of Systemic Biomarkers of Hematologic Function (Except Hemoglobin & Hematocrit)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visit in a subgroup of participants consented to contribute samples.

  4. Baseline Values of Systemic Biomarkers of Hematologic Function (Hemoglobin)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visit in a subgroup of participants consented to contribute samples.

  5. Baseline Values of Systemic Biomarkers of Hematologic Function (Hematocrit)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visit in a subgroup of participants consented to contribute samples.

  6. Changes Relative to Baseline (Percent Change) of Systemic Biomarkers of Hematologic Function

    Time frame: Weeks 0, 2 and 10

    These will be assessed by blood samples taken at specific visits of the study in a subgroup of participants consented to contribute samples.

  7. Baseline Values of Systemic Biomarkers of Inflammation and Immunologic Function (Parameters in pg/mL)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visits of the study in a subgroup of participants consented to contribute samples.

  8. Baseline Values of Systemic Biomarkers of Inflammation and Immunologic Function (Calprotectin, C-reactive Protein)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visits of the study in a subgroup of participants consented to contribute samples.

  9. Baseline Values of Systemic Biomarkers of Inflammation and Immunologic Function (Serotonin, Tryptophan and Taurine)

    Time frame: Week 0

    These will be assessed by blood samples taken at randomization visits of the study in a subgroup of participants consented to contribute samples.

  10. Changes Relative to Baseline (Percent Change) of Systemic Biomarkers of Inflammation and Immunologic Function

    Time frame: Weeks 0, 2 and 10

    These will be assessed by blood samples taken at specific visits of the study in a subgroup of participants consented to contribute samples.

  11. Biomarkers of Pharmacodynamic Activity - Plasma Retinol

    Time frame: Weeks 0, 2 and 10

    These will be assessed by blood samples taken at specific visits of the study in a subgroup of participants consented to contribute samples.

  12. Biomarkers of Pharmacodynamic Activity - Systematic Inflammation Index (SII)

    Time frame: Weeks 0, 2 and 10

    These will be assessed by blood samples taken at specific visits of the study in a subgroup of participants consented to contribute samples. SII = (N × P)/L, where N, P and L (cells*10^9/L) represent absolute neutrophil counts, platelet counts and lymphocyte counts. Since SII is a ratio of concentrations, it is unitless.

  13. Changes Relative to Baseline (Percent Change) of Biomarker of Pharmacodynamic Activity - Retinol

    Time frame: Weeks 0, 2 and 10

    These will be assessed by blood samples taken at specific visits of the study in a subgroup of participants consented to contribute samples.

Sponsors and collaborators

Lead sponsor

Laurent Pharmaceuticals Inc.

Industry

Registry information

Official study title

A DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED, ADAPTIVE PHASE 2/3 STUDY OF THE EFFICACY OF LAU-7b IN THE TREATMENT OF ADULTS WITH LONG COVID AND MODERATE TO SEVERE SYMPTOMS

Acronym: ESSOR

Important dates

Study start
2023
Primary completion
2024
Study completion
2024
First posted
Aug 21, 2023
Registry last updated
Jan 6, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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