BCD-131 is pegylated darbepoetin beta. BCD-131-1 is open clinical trial to evaluate pharmacokinetics, pharmacodynamics, tolerance, safety and immunogenicity of single injection of increasing doses of BCD-131 to healthy volunteers compared to Mircera® and Aranesp®. Clinical trial will be conducted in two stages. On first stage the optimal dose for therapeutic use of BCD-131 will be determined (subcutaneous injections). On second stage the determined dose will be injected subcutaneously and intravenously.