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<i>Echinacea purpurea</i> has been shown to broadly inhibit coronaviruses and SARS-CoV-2 in vitro. This review discusses the available clinical evidence from randomized, blinded and controlled human studies. Two RCTs capturing incidence of viral respiratory tract infections during <i>Echinacea</i> preventative treatment were identified including coronavirus infections. Incidence and/or viral loads were measured by RT-PCR and symptom severity was recorded. In a first study, Jawad et al. collected nasopharyngeal swabs from adults (N = 755) over 4 months of continuous prevention. Overall, 24 and 47 enveloped virus infections occurred, including 21 and 33 coronavirus detections (229E; HKU1; OC43) with Echinaforce^® extract (2400 mg daily) and placebo, respectively (<i>p</i> = 0.0114). In a separate study, Ogal et al. administered the same extract (1200 mg) or control for 4 months to children (4–12 years) (N = 203). <i>Echinacea</i> reduced the incidence of enveloped virus infections from 47 to 29 (<i>p</i> = 0.0038) whereas 11 and 13 coronavirus detections (229E, OC43, NL63) were counted (<i>p</i> > 0.05). Respiratory symptoms during coronavirus infections were significantly lower with area-under-curve AUC = 75.8 (+/−50.24) versus 27.1 (+/−21.27) score points (<i>p</i> = 0.0036). Importantly, viral loads in nasal secretions were significantly reduced by 98.5% in the <i>Echinacea</i> group, with Ct-values 31.1 [95% CI 26.3; 35.9] versus 25.0 [95% CI 20.5; 29.5] in the control group (<i>p</i> = 0.0479). Results from clinical studies confirm the antiviral activity found for <i>Echinacea</i> in vitro, embracing enveloped respiratory pathogens and therefore coronaviruses as well. Substantiating results from a new, completed study seem to extrapolate these effects to the prevention of SARS-CoV-2 infections. As hypothesized, the established broad antiviral activity of <i>Echinacea</i> extract appears to be inclusive for SARS-CoV-2.