Safety and efficacy of lentinan nasal drops in patients infected with
the variant of COVID-19: a single-center, randomized, placebo-controlled
trial
Abstract
Objective: Lentinan has antiviral, anti-tumor,
immunomodulatory, stimulating interferon production, and other
pharmacological effects. Previous animal experiments have shown that
lentinan nasal drops can assist(Corona Virus Disease 2019,COVID-19)
vaccine to induce high levels of neutralizing antibodies and can
effectively resist the invasion of severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2). This study aimed to evaluate the safety and
efficacy of lentinan nasal drops in patients infected with COVID-19
through a dose-escalation study and a placebo-controlled trial.
Methods: The study was divided into two phases: Phase I: a dose
escalation trial in which 24 COVID-19 patients were enrolled, that is,
12 in the escalation dose group (50, 75, and 100 µg/day) and 12 in the
standard treatment group. The aim was to evaluate the safety and
tolerance of lentinan nasal drops. The second stage was a
placebo-controlled study. The optimal dose group of the first stage was
used as the therapeutic dose, and the sample size was expanded to verify
the anti-COVID-19 efficacy of lentinan nasal drops. Results: In
the dose-increasing study, lentinan nasal drops showed good safety, and
no serious adverse reactions occurred. The virus shedding time of the
100 µg dose group was significantly shorter than that in the control
group (7.75±1.71 VS 13.41±3.8 d) (p=0.01), and the 100 µg/day lentinan
nasal drops were tolerated well. The results of the placebo-controlled
study showed that compared with that in the placebo group, the time for
COVID-19 antigen to turn negative was significantly shorter in the 100
µg lentinan nasal drop group (p=0.0298), but no significant difference
was observed in symptom improvement between the two groups. In the
placebo-controlled study, two patients experienced mild nasal discomfort
with nasal drops, but the symptoms relieved themselves.
Conclusion: Lentinan nasal drops are tolerated well and can
shorten the time of virus clearance.