inclusion criteria: 1. willing and able to provide informed consent for the trial, written, electronic, verbal, or other method deemed acceptable by the institution and irb. 2. subjects between ≥18 and ≤65 years of age. 3. subjects found positive for sars-cov-2 either by rapid antigen test or by reverse transcription polymerase chain reaction (rt-pcr) using icmr-validated kit. note: test need not be repeated in those with possession of confirmed positive report, but positive result test date must be ≤5 days of first dose of study drug. 4. mild or moderate covid-19 as per latest updated version of clinical management protocol for covid-19 (in adults) released by government of india ministry of health and family welfare directorate general of health services (emr division). 5. the effects of brequinar on the developing human fetus are unknown. for this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. men and women treated or enrolled on this protocol must also agree to use adequate contraception for the duration of study participation, and for 90 days after completion of brequinar administration. 6. male subjects must agree to refrain from sperm donation and female subjects must agree to refrain from ovum donation from initial study drug administration until 90 days after the last dose of brequinar. 7. at least one non-respiratory covid-19 symptom characterized as mild to moderate by the investigator including but not limited to fatigue, chills, fever, body aches, nasal congestion, nausea, vomiting, or other sign or symptom commonly associated with covid-19 in the opinion of the investigator. symptom onset must be ≤5 days prior to first dose. subject must have one or more signs/symptoms present at first dose. 8. willing to participate in the pk subset if at one of the identified sites. 9. able to swallow capsules.

inclusion criteria: 1. willing and able to provide informed consent for the trial, written, electronic, verbal, or other method deemed acceptable by the institution and irb. 2. subjects between ≥18 and ≤65 years of age. 3. subjects found positive for sars-cov-2 either by rapid antigen test or by reverse transcription polymerase chain reaction (rt-pcr) using icmr-validated kit. note: test need not be repeated in those with possession of confirmed positive report, but positive result test date must be ≤5 days of first dose of study drug. 4. mild or moderate covid-19 as per latest updated version of clinical management protocol for covid-19 (in adults) released by government of india ministry of health and family welfare directorate general of health services (emr division). 5. the effects of brequinar on the developing human fetus are unknown. for this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. men and women treated or enrolled on this protocol must also agree to use adequate contraception for the duration of study participation, and for 90 days after completion of brequinar administration. 6. male subjects must agree to refrain from sperm donation and female subjects must agree to refrain from ovum donation from initial study drug administration until 90 days after the last dose of brequinar. 7. at least one non-respiratory covid-19 symptom characterized as mild to moderate by the investigator including but not limited to fatigue, chills, fever, body aches, nasal congestion, nausea, vomiting, or other sign or symptom commonly associated with covid-19 in the opinion of the investigator. symptom onset must be ≤5 days prior to first dose. subject must have one or more signs/symptoms present at first dose. 8. willing to participate in the pk subset if at one of the identified sites. 9. able to swallow capsules.

inclusion criteria: willing and able to provide informed consent for the trial, written, electronic, verbal, or other method deemed acceptable by the institution and irb. subjects between ≥18 and ≤65 years of age. subjects found positive for sars-cov-2 either by rapid antigen test or by reverse transcription polymerase chain reaction (rt-pcr) using icmr-validated kit. note: test need not be repeated in those with possession of confirmed positive report, but positive result test date must be ≤5 days of first dose of study drug. mild or moderate covid-19 as per latest updated version of clinical management protocol for covid-19 (in adults) released by government of india ministry of health and family welfare directorate general of health services (emr division). the effects of brequinar on the developing human fetus are unknown. for this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. men and women treated or enrolled on this protocol must also agree to use adequate contraception for the duration of study participation, and for 90 days after completion of brequinar administration. male subjects must agree to refrain from sperm donation and female subjects must agree to refrain from ovum donation from initial study drug administration until 90 days after the last dose of brequinar. at least one non-respiratory covid-19 symptom characterized as mild to moderate by the investigator including but not limited to fatigue, chills, fever, body aches, nasal congestion, nausea, vomiting, or other sign or symptom commonly associated with covid-19 in the opinion of the investigator. symptom onset must be ≤5 days prior to first dose. subject must have one or more signs/symptoms present at first dose. willing to participate in the pk subset if at one of the identified sites. able to swallow capsules.

inclusion criteria: willing and able to provide informed consent for the trial, written, electronic, verbal, or other method deemed acceptable by the institution and irb. subjects between ≥18 and ≤65 years of age. subjects found positive for sars-cov-2 either by rapid antigen test or by reverse transcription polymerase chain reaction (rt-pcr) using icmr-validated kit. note: test need not be repeated in those with possession of confirmed positive report, but positive result test date must be ≤5 days of first dose of study drug. mild or moderate covid-19 as per latest updated version of clinical management protocol for covid-19 (in adults) released by government of india ministry of health and family welfare directorate general of health services (emr division). the effects of brequinar on the developing human fetus are unknown. for this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. men and women treated or enrolled on this protocol must also agree to use adequate contraception for the duration of study participation, and for 90 days after completion of brequinar administration. male subjects must agree to refrain from sperm donation and female subjects must agree to refrain from ovum donation from initial study drug administration until 90 days after the last dose of brequinar. at least one non-respiratory covid-19 symptom characterized as mild to moderate by the investigator including but not limited to fatigue, chills, fever, body aches, nasal congestion, nausea, vomiting, or other sign or symptom commonly associated with covid-19 in the opinion of the investigator. symptom onset must be ≤5 days prior to first dose. subject must have one or more signs/symptoms present at first dose. willing to participate in the pk subset if at one of the identified sites. able to swallow capsules.