Pharmacokinetic Parameters of Oral Pegylated IFN-λ1.

We studied the pharmacokinetics of a pegylated IFN-λ1 (PEG IFN-λ1) after its oral administration to rats in different therapeutic doses. The hypothesis on linear pharmacokinetics of PEG IFN-λ1 within the dose range of 2.6-7.8 µg/kg was confirmed, high for protein molecules bioavailability from 17.5 to 21%, the absence of intravascular deposition, and effective elimination with feces and urine (85 and 15% of the administered dose, respectively) were demonstrated. At the same time, the mean retention time for PEG IFN-λ1 in the circulation is 6.46-6.65 h and half-life is 3 h. These findings give ground for continuing experimental studies of PEG IFN-λ1 pharmacokinetics, in particular, tissue distribution of the drug.

Evaluation of the Anti-Viral Activity of Human Recombinant Interferon Lambda-1 against SARS-CoV-2.

The antiviral activity of recombinant human IFN-lambda type 1 (IFNλ-1) against culture strain of SARS-CoV-2 virus was determined by infecting a highly sensitive VeroE6 coronavirus cell culture after preincubation test (the cell monolayer was incubated with 4-fold dilutions of IFNλ-1 in a concentration range of 0.16-42,500 ng/ml in a culture medium for 12 h at 37°C) and without preincubation (simultaneous addition of different concentrations of IFNλ-1 and SARS-CoV-2 infection in a dose of 102 TCID50). The created recombinant human IFNλ-1 demonstrated obvious antiviral activity against SARS-CoV-2 virus in vitro. In the tests with and without preincubation, IFNλ-1 exhibited significant activity, although somewhat lower in variant with simultaneous addition of IFNλ-1 and virus to the cell culture. It should be noted that the antiviral effect of IFNλ-1 was observed in a wide range of concentrations.