inclusion criteria: * subject provides written informed consent prior to initiation of any study procedures. understands and agrees to comply with planned study procedures. * male or non-pregnant female adult ≥18 years of age at time of enrolment. * has laboratory-confirmed sars-cov-2 infection as determined by pcr and fulfils the case criteria of covid-19 (one or more of the following must be met in lieu of a positive pcr test: fever \[defined as a temperature ≥ 100.0°f / 37.8°c documented within 24 hr. of randomization\] , absolute and relative lymphopenia and leukopenia, new typical infiltrates in x-ray of the chest or chest ct scan \[only if obtained for clinical reasons; not required by study\], no improvement on antibiotics). * scoring a "3" or "4" (or "5", at the investigator's discretion) on the 7-point ordinal scale (see outcome measures) at enrolment. note, if scoring a "2" at screening, inclusion will be met if the patient is in the process of being hospitalized or admitted to an inpatient setting. such a patient would be assigned a "3" at enrolment for baseline assessment purposes. * no participation in other clinical trials according to the german medicines act (amg) (3 months before) at the time of this trial.

inclusion criteria: * subject provides written informed consent prior to initiation of any study procedures. understands and agrees to comply with planned study procedures. * male or non-pregnant female adult ≥18 years of age at time of enrolment. * has laboratory-confirmed sars-cov-2 infection as determined by pcr and fulfils the case criteria of covid-19 (one or more of the following must be met in lieu of a positive pcr test: fever \[defined as a temperature ≥ 100.0°f / 37.8°c documented within 24 hr. of randomization\] , absolute and relative lymphopenia and leukopenia, new typical infiltrates in x-ray of the chest or chest ct scan \[only if obtained for clinical reasons; not required by study\], no improvement on antibiotics). * scoring a "3" or "4" (or "5", at the investigator's discretion) on the 7-point ordinal scale (see outcome measures) at enrolment. note, if scoring a "2" at screening, inclusion will be met if the patient is in the process of being hospitalized or admitted to an inpatient setting. such a patient would be assigned a "3" at enrolment for baseline assessment purposes. * no participation in other clinical trials according to the german medicines act (amg) (3 months before) at the time of this trial.

inclusion criteria: - subject provides written informed consent prior to initiation of any study procedures. understands and agrees to comply with planned study procedures. - male or non-pregnant female adult ≥18 years of age at time of enrolment. - has laboratory-confirmed sars-cov-2 infection as determined by pcr and fulfils the case criteria of covid-19 (one or more of the following must be met in lieu of a positive pcr test: fever [defined as a temperature ≥ 100.0°f / 37.8°c documented within 24 hr. of randomization] , absolute and relative lymphopenia and leukopenia, new typical infiltrates in x-ray of the chest or chest ct scan [only if obtained for clinical reasons; not required by study], no improvement on antibiotics). - scoring a "3" or "4" (or "5", at the investigator's discretion) on the 7-point ordinal scale (see outcome measures) at enrolment. note, if scoring a "2" at screening, inclusion will be met if the patient is in the process of being hospitalized or admitted to an inpatient setting. such a patient would be assigned a "3" at enrolment for baseline assessment purposes. - no participation in other clinical trials according to the german medicines act (amg) (3 months before) at the time of this trial.

inclusion criteria: - subject provides written informed consent prior to initiation of any study procedures. understands and agrees to comply with planned study procedures. - male or non-pregnant female adult ≥18 years of age at time of enrolment. - has laboratory-confirmed sars-cov-2 infection as determined by pcr and fulfils the case criteria of covid-19 (one or more of the following must be met in lieu of a positive pcr test: fever [defined as a temperature ≥ 100.0°f / 37.8°c documented within 24 hr. of randomization] , absolute and relative lymphopenia and leukopenia, new typical infiltrates in x-ray of the chest or chest ct scan [only if obtained for clinical reasons; not required by study], no improvement on antibiotics). - scoring a "3" or "4" (or "5", at the investigator's discretion) on the 7-point ordinal scale (see outcome measures) at enrolment. note, if scoring a "2" at screening, inclusion will be met if the patient is in the process of being hospitalized or admitted to an inpatient setting. such a patient would be assigned a "3" at enrolment for baseline assessment purposes. - no participation in other clinical trials according to the german medicines act (amg) (3 months before) at the time of this trial.