The given invention is related to the field of medicine, namely to experimental research in oncology, and can be used to obtain a pharmaceutical agent for inhibiting the proliferation of HeLa cervical cancer cells. It entails the use of a metal powder obtained in a gaseous medium by means of an electric explosion of a wire made of low-carbon steel carried out with a specific energy of 7-18 kJ/g and a pulse duration of 1.2-2 µs. The explosion is carried out inside a reactor that is pre-evacuated to a residual pressure of 10-2 Pa, and then filled with carbon monoxide to a pressure of 105 Pa at a gas circulation rate flow of 10 m/s. The products of the explosion deposited in a hopper are passivated in air for at least 48 hours. The resulting powder is extracted and mixed with a solution of the RPMI-1640 nutrient medium with L-glutamine, a pH of 7.2, in the proportion of the mass of the powder to the volume of the specified solution from 1:10 to 2.7: 10. The solution is then centrifuged until the phases are separated. The liquid phase is decanted and used as a pharmaceutical agent. The purpose of the given invention is to expand the arsenal of tools for inhibiting the proliferation of tumor cells.