Virus inactivation method, method for manufacturing protein drug, and system for purifying solution

A method for manufacturing an antibody drug or an antibody fragment drug comprising:

• artificially expressing an antibody drug or an antibody fragment drug;
• and
• inactivating viruses contained in a solution containing the artificially expressed antibody drug or antibody fragment drug by irradiating the solution with ultraviolet rays in the presence of a radical scavenger, wherein
• the irradiating only aggregates 5% or less of the antibody or antibody fragment,
• a wavelength of the ultraviolet rays is 200 nm or longer and 315 nm or shorter,
• an irradiation amount of the ultraviolet rays is 300 mJ/cm2 or more,
• an irradiation time of the ultraviolet rays is 3 minutes or less, and
• a concentration of the radical scavenger in the solution is 0.03 mM or more.

A system for purifying a solution containing an artificially expressed antibody or antibody fragment, comprising:

• a first purification unit configured to purify the solution containing the artificially expressed antibody or antibody fragment by chromatography;
• a virus inactivation unit configured to irradiate the solution containing the antibody or antibody fragment resulting from the first purification unit with ultraviolet rays in the presence of a radical scavenger, the virus inactivation unit comprising:
• a channel having an inlet and an outlet for the solution and an ultraviolet-transmitting portion provided in at least a portion between the inlet and the outlet;
• and
• a light source configured to emit ultraviolet rays to the ultraviolet-transmitting portion;
• and
• a second purification unit configured to further purify, by chromatography, the solution containing the antibody or antibody fragment irradiated with the ultraviolet rays by the inactivation unit, wherein
• the irradiation of the solution containing the antibody or antibody fragment by the inactivation unit only aggregates 5% or less of the antibody or antibody fragment,
• a wavelength of the ultraviolet rays is 200 nm or longer and 315 nm or shorter,
• an irradiation amount of the ultraviolet rays is 300 mJ/cm2 or more,
• an irradiation time of the ultraviolet rays is 3 minutes or less, and
• a concentration of the radical scavenger in the solution is 0.03 mM or more, and
• the outlet of the channel of the inactivation unit is connected to an inlet of a column for the chromatography which the second purification unit comprises.