Intraoperative trifunctional antibody application for prophylaxis of intraperitoneal tumor cell dissemination

1. A method for destroying tumor cells, the method comprising:

Administering directly and locally into a human patient's abdominal cavity, during surgical removal of a tumor located in the patient's abdominal cavity, a pharmaceutical composition comprising a trifunctional, bispecific and/or trispecific antibody, wherein the trifunctional, bispecific and/or trispecific antibody

binds to a T cell via CD3;

binds to at least one tumor-associated antigen which is expressed on the tumor cells; and

binds by its Fc part (in the case of bispecific antibodies) or by a third specificity (in the case of trispecific antibodies) to Fc receptor-positive cells,

wherein the antibody is administered in an amount of about 1 to about 400 μg.

2. The method according to claim 1 , wherein the pharmaceutical composition comprises a physiologically acceptable medium designed for application into the abdominal cavity.

3. The method according to claim 2 , wherein the medium containing the antibody remains in the abdominal cavity for a period of time which is sufficient to establish contact between the antibody and disseminated tumor cells and the medium is then removed again with the antibody, or the medium remains in the abdominal cavity with the antibody and is absorbed there.

4. The method according to claim 1 , wherein the antibody is administered in an amount of about 5 to about 100 μg.

5. The method according to claim 1 , wherein the antibody is directed against a tumor antigen chosen from the group consisting of Her2/neu, CD20, CD30, EpCAM, G250, proteoglycans, GD2, GD3, MHC II, EGF-R, CA125 and CEA.

6. The method according to claim 1 , wherein the antibody binds to type I and/or type III Fc-γ receptor-positive cells via its Fc content.

7. The method according to claim 1 , wherein the antibody is an anti-CD3 X anti-tumor-associated antigen bispecific antibody.

8. The method according to claim 1 , wherein the antibody is a bispecific antibody chosen from a group consisting of a heterologous bispecific antibody and a heterologous rat/mouse bispecific antibody.

9. The method according to claim 1 , wherein the antibody comprises an isotype combinations in the Fc region which is selected from the group consisting of:

rat IgG2b/mouse IgG2a, rat IgG2b/mouse IgG2b, rat IgG2b/human IgG1, and rat IgG2b/human IgG2.

10. The method according to claim 1 , wherein the antibody has the following isotype combination:

mouse [VH-CH1, VL-CL]-human IgG1-[hinge]-human IgG1-[CH2-CH3]/rat [VH-CH1, VL-CL]-human IgG1-[hinge]-human IgG3 [Caucasian allotypes G3m(b+g) =no binding to protein A]-[CH2-CH3];

and/or the antibody is an anti-Her2/neu x anti-CD3 antibody or an anti-EpCAMx anti-CD3 antibody which binds to type I/III Fc-γ receptors, with the isotype combination rat IgG2b/mouse IgG2a.

11. The method according to claim 1 , further comprising administering the trifunctional, bispecific or trispecific antibody postoperatively in at least one further dose.

12. The method according to claim 11 , wherein the antibody is administered postoperatively in a second dose and third dose.

13. The method according to claim 11 , wherein the antibody is administered postoperatively as the second dose in an amount of about 1 to about 20 μg, a subsequent dose in an amount of about 20 to about 100 μg, and any further subsequent administration in an amount of about 100 to about 500 μg.

14. The method according to claim 11 , wherein the antibody is administered postoperatively in an amount of about 5 to about 1,000μg, intraperitoneally, and wherein the postoperative administration is carried out 2-5 times.

15. The method according to claim 1 , wherein the antibody is administered in an amount of about 10 to about 50 μg.

16. The method according to claim 1 , wherein the antibody is further administered postoperatively as the second dose in an amount of in an amount of about 5 to about 10 μg, a subsequent dose in an amount of about 30 to about 60 μg, and any further subsequent administration in an amount of about 100 to about 300 μg.

17. The method according to claim 1 , wherein the antibody is further administered postoperatively and intraperitoneally in an amount of about 10-500 μg, and wherein the postoperative administration is carried out 2-5 times.

18. The method according to claim 1 , wherein the antibody is further administered postoperatively and intraperitoneally in an amount of about 10 to about 150 μg, and wherein the postoperative administration is carried out 2-5 times.

19. The method according to claim 11 , wherein the postoperative administration takes place 48-72 hours after the tumor is surgically removed.

20. The method according to claim 11 , wherein the postoperative administration continues over a period of up to 12-20 days.