inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard reverse transcriptase-polymerase chain reaction (rt-pcr) assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (\>12 weeks). clinical symptoms include the following: * respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. * neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. * cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. * musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. * general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: * ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. * ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives \[male condom, female condom, or diaphragm with a spermicidal gel\], hormonal contraceptives \[implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings\], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard reverse transcriptase-polymerase chain reaction (rt-pcr) assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (\>12 weeks). clinical symptoms include the following: * respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. * neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. * cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. * musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. * general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: * ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. * ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives \[male condom, female condom, or diaphragm with a spermicidal gel\], hormonal contraceptives \[implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings\], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: male or female adult ≥ 18 years of age at time of enrollment. prior confirmed covid-19 diagnosis by standard reverse transcriptase-polymerase chain reaction (rt-pcr) assay or equivalent testing clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: male or female adult ≥ 18 years of age at time of enrollment. prior confirmed covid-19 diagnosis by standard reverse transcriptase-polymerase chain reaction (rt-pcr) assay or equivalent testing clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: male or female adult ≥ 18 years of age at time of enrollment. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: male or female adult ≥ 18 years of age at time of enrollment. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. - musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. - general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea. - musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling. - general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). note: clinical symptom score is obtained from the patient diary (refer to appendix 1 for scoring instructions). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest etc. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste etc. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea, etc. - musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling - general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, other flu-like symptoms, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing 3. clinical symptom score of ≥6 and at least two symptoms of moderate or higher severity as listed below at the time of screening and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>12 weeks). clinical symptoms include the following: - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest etc. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste etc. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea, etc. - musculoskeletal symptoms such as muscle aches/cramps, muscle weakness, joint pain/swelling - general immune response symptoms such as fatigue (low energy or tiredness), chills or shivering, feeling hot or feverish, other flu-like symptoms, or exertional malaise (feeling of discomfort, illness, or lack of well-being after physical activity or mental stress). 4. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 5. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 6. men and women of childbearing potential and their partner must agree to use two medically accepted methods of contraception (e.g., barrier contraceptives [male condom, female condom, or diaphragm with a spermicidal gel], hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], or one of the following methods of birth control (intrauterine devices, bilateral tubal occlusion, or vasectomy) or must practice complete sexual abstinence for the duration of the study (excluding women who are not of childbearing potential and men who have been sterilized). 7. females of child-bearing potential must have a negative urine pregnancy test at screening visit and prior to receiving the first dose of study drug; and male participants must agree to use contraception and refrain from donating sperm for at least 90 days after the last dose of study intervention. 8. subject is willing and able to comply with scheduled visits, drug administration plan, laboratory tests, other study procedures and study restrictions

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. patient with prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>6 weeks). - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest etc. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste etc. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea, etc. - general immune response symptoms such as fatigue (low energy or tiredness), muscle cramps, joint pain, chills or shivering, feeling hot or feverish or other flu-like symptoms. 3. clinical symptom score of ≥6 with at least two symptoms of moderate or higher severity at the time of screening. 4. chalder fatigue scale bimodal score ≥ 4 at the time of screening 5. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 6. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 7. understands and agrees to comply with planned study procedures. 8. women of childbearing potential and their partner must agree to use at least one highly effective method of contraception (e.g., hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], intrauterine devices, bilateral tubal occlusion, or sexual abstinence) for the duration of the study.

inclusion criteria: 1. male or female adult ≥ 18 years of age at time of enrollment. 2. patient with prior confirmed covid-19 diagnosis by standard rt-pcr assay or equivalent testing and currently experiencing two or more of the following symptoms consistent with covid-19 infection for a prolonged period of time (>6 weeks). - respiratory symptoms such as cough, sore throat, stuffy or runny nose, shortness of breath (difficulty breathing), tightness of chest etc. - neurological symptoms such as difficulty in concentration (brain fog), sleep disturbance/insomnia, headache, dizziness, anxiety, tingling or numbness, loss of sense of smell or taste etc. - cardiovascular and gastrointestinal symptoms such as feeling of fast heartbeat, nausea, vomiting, diarrhea, etc. - general immune response symptoms such as fatigue (low energy or tiredness), muscle cramps, joint pain, chills or shivering, feeling hot or feverish or other flu-like symptoms. 3. clinical symptom score of ≥6 with at least two symptoms of moderate or higher severity at the time of screening. 4. chalder fatigue scale bimodal score ≥ 4 at the time of screening 5. electrocardiogram (ecg) with no clinically significant findings as assessed by the investigator. note: below are the examples of clinically significant and non-clinically significant ecg abnormalities: - ecg findings indicative of acute myocardial infarction or acute ischemic changes would be considered clinically significant abnormalities. - ecg finding such as atrial fibrillation, atrial flutter, paced rhythms in individuals who have undergone permanent pacemaker placement, evidence of prior infarction, unchanged stable conduction abnormalities e.g. right bundle branch block, or any other finding which does not significantly impact mortality would be considered non-clinically significant findings and subjects with these abnormal findings would be allowed to enroll in the study. 6. subject (or legally authorized representative) provides written informed consent prior to initiation of any study procedures. 7. understands and agrees to comply with planned study procedures. 8. women of childbearing potential and their partner must agree to use at least one highly effective method of contraception (e.g., hormonal contraceptives [implants, injectables, combination oral contraceptives, transdermal patches, or contraceptive rings], intrauterine devices, bilateral tubal occlusion, or sexual abstinence) for the duration of the study.