1. A stable antibody-containing liquid composition, characterized in that it contains arginine and methionine. 2. The composition of claim 1, further comprising a histidine buffering agent. The composition of claim 2, further comprising a surfactant. The composition according to any one of paragraphs. 1-3, containing the antibody in an amount of at least 50 mg / ml. 5. The composition according to any one of paragraphs. 1-3, containing the antibody in an amount of at least 100 mg / ml. 6. The composition according to any one of paragraphs. 1-3, containing the antibody in an amount of at least 120 mg / ml. 7. The composition according to any one of paragraphs. 1-3, where the antibody is an antibody to the receptor of IL-6.8. A stable liquid composition containing an antibody to the IL-6 receptor, characterized in that it contains either arginine or methionine. 9. The composition according to any one of paragraphs. 1, 2, 3 and 8, where the antibody is a humanized antibody or a human antibody. 10. The composition according to any one of paragraphs. 1, 2, 3 and 8, additionally containing tryptophan. 11. The composition according to any one of paragraphs. 1, 2, 3 and 8, having a pH in the range from 4 to 8.12. The composition according to any one of paragraphs. 1, 2, 3, and 8, where arginine is present in an amount of 50 to 1500 mM. 13. The composition according to any one of paragraphs. 1, 2, 3 and 8, having a viscosity of 2 to 15 MPa · s. 14. The composition according to any one of paragraphs. 1, 2, 3 and 8, which is stable at 22-28 ° C for at least 6 months. 15. The composition according to any one of paragraphs. 1, 2, 3 and 8, characterized in that the dimerization of antibody molecules is inhibited. The composition according to any one of paragraphs. 1, 2, 3 and 8, characterized in that the deamidation of antibody molecules is inhibited. 17. The composition according to any one of paragraphs. 1, 2, 3 and 8, which is intended for subcutaneous administration. 18. The
