New clinical research suggests that an herbal medicinal product containing a proprietary combination of a concentrated echinacea herb and root extract is as effective as the conventional antiviral medicine oseltamivir (Tamiflu®) in the early treatment of influenza.
The results of the randomized, double-blind, controlled clinical trial were published in the open-access journal Current Therapeutic Research.
For the study, researchers recruited 473 patients who had exhibited flu symptoms for less than 48 hours from 29 primary care practices in the Czech Republic.
The patients were randomly assigned to take Echinaforce® Hotdrink syrup, a beverage containing an alcoholic extract prepared from freshly harvested echinacea (Echinacea purpurea) herb and root (95% herb; 5% root) supplemented with European elderberry (Sambucus nigra), for 10 days, or oseltamivir for five days followed by placebo for five days.
Echinaforce Hotdrink is produced and marketed by A. Vogel Bioforce AG of Roggwil, Switzerland. It is not currently sold in the United States.
The primary endpoint of the clinical trial was the percentage of patients with mild or no symptoms after one, five, and 10 days of treatment. At each time point, the researchers found that a similar number of patients had recovered in both groups.
After day one, 1.5% of patients in the Echinaforce Hotdrink group and 4.1% of those in the oseltamivir group exhibited mild or no symptoms; recovery rates for days five and 10 were 50.2% and 48.8%, and 90.1% and 84.8%, respectively.
Statistical analyses revealed that the two treatments were, in fact, non-inferior to each other; that is, they were approximately equal in their therapeutic effects. When the researchers looked at a subgroup of patients with laboratory-confirmed influenza (as opposed to those with a clinical flu diagnosis), recovery rates still did not vary between the two actives.
Finally, there was a trend towards a higher proportion of recovered patients after 10 days of treatment with Echinaforce Hotdrink.
“This is yet another significant human clinical trial that helps to document the clinical benefits of this specific Swiss echinacea extract,” said Mark Blumenthal, founder and executive director of the American Botanical Council, a leading non-profit research and education organization.
“The size of this trial — 473 patients — is one of the largest echinacea clinical trials ever published,” added Blumenthal, who noted that the largest echinacea clinical trial in the scientific literature — with 755 subjects — was conducted with the same Echinaforce extract, and showed a preventive effect against respiratory tract infections.
“It is rewarding to see an herbal products manufacturer investing resources in a well-designed clinical study on a phytotherapeutic product,” noted Stefan Gafner, PhD, ABC’s chief science officer. “The combination of echinacea and European elderberry has resulted in the same treatment outcome as the standard drug oseltamivir in the study population, providing evidence for the safety and efficacy of this product.”
There were also no statistically significant differences between groups in terms of antibiotic use, intermediate doctor visits, use of over-the-counter medications for symptoms, “ability to return to normal daily activities,” or physician and patient-reported efficacy of the treatments.
“Echinaforce Hotdrink has here been demonstrated as attractive therapy for acute influenza treatment with better safety and comparable efficacy profile to the neuraminidase inhibitor Oseltamivir. Its availability as over-the-counter medicine allows for a very early treatment start, which is central for treatment success with any intervention,” the authors concluded.