Methods of treating neutorpenia using G-CSF protein complex

1. A method of treating a condition in a subject in need thereof, the condition characterized by compromised white blood cell production in the subject, the method comprising administering to the subject a therapeutically effective amount of a chemotherapeutic regimen followed by a therapeutically effective amount of a protein complex comprising a modified human granulocyte-colony stimulating factor (hG-CSF) covalently linked to an immunoglobulin Fc region via a non-peptidyl polymer, wherein the non-peptidyl polymer is site-specifically linked to an N-terminus of the immunoglobulin Fc region and the modified hG-CSF comprises the amino acid sequence of SEQ ID NO: 1, wherein the protein complex is administered on the same day as the chemotherapeutic regimen.

2. The method of claim 1 , wherein the condition is selected from the group consisting of: reduced hematopoietic function, reduced immune function, reduced neutrophil count, reduced neutrophil mobilization, mobilization of peripheral blood progenitor cells, sepsis, severe chronic neutropenia, bone marrow transplants, infectious diseases, leucopenia, thrombocytopenia, anemia, enhancing engraftment of bone marrow during transplantation, enhancing bone marrow recovery in treatment of radiation, chemical or chemotherapeutic induced bone marrow aplasia or myelosuppression, and acquired immune deficiency syndrome.

3. The method of claim 2 , wherein myelosuppression is neutropenia.

4. The method of claim 3 , wherein neutropenia is febrile neutropenia.

5. The method of claim 1 , wherein said compromised white blood cell production is a result of chemotherapy, radiation therapy, or idiopathic thrombocytopenic purpura.

6. The method of claim 1 , wherein the protein conjugate is administered after the subject is treated with adjuvant or neoadjuvant chemotherapy.

7. The method of claim 1 , wherein the protein conjugate is administered between 1 and 5 days after the subject is treated with adjuvant or neoadjuvant chemotherapy.

8. The method of claim 7 , wherein the adjuvant or neoadjuvant chemotherapy is a combination of docetaxel and cyclophosphamide.

9. The method of claim 1 , wherein a second dose of the protein conjugate is administered between 15 and 25 days after a first dose of the protein conjugate is administered to the subject.

10. The method of claims 1 , wherein the therapeutically effective amount is a unit dosage between about 5 μg/kg and about 200 μg/kg.

11. The method of claim 10 , wherein the therapeutically effective amount is a unit dosage form selected from: about 9 μg/kg, about 25 μg/kg, about 26 μg/kg, about 50 μg/kg, about 52 μg/kg, about 100 μg/kg, about 88 μg/kg, and about 200 μg/kg.

12. The method of claim 11 , wherein the therapeutically effective amount is 13.2 mg of the protein conjugate in a 0.6 mL dosage volume.

13. The method of claims 1 , further comprising administering to the subject a therapeutically effective amount of a second agent.

14. The method of claim 1 , wherein the immunoglobulin Fc region comprises a polypeptide sequence of SEQ ID NO: 2.

15. The method of claim 1 , wherein both ends of the non-peptidyl polymer are respectively linked to the modified human G-CSF and the immunoglobulin Fc region through reactive groups by a covalent bond.

16. The method of claim 15 , wherein the reactive group of the non-peptidyl polymer is selected from the group consisting of an aldehyde group, a maleimide group, and a succinimide derivative.

17. The method of claim 16 , wherein:

(a) the non-peptidyl polymer has an aldehyde group as a reactive group at both ends;

(b) the non-peptidyl polymer has an aldehyde group and a maleimide group as a reactive group at both ends, respectively; or

(c) the non-peptidyl polymer has an aldehyde group and a succinimide group as a reactive group at both ends, respectively.

18. The method of claim 1 , wherein:

(a) the immunoglobulin Fc region is aglycosylated;

(b) the immunoglobulin Fc region consists of one to four domains selected from the group consisting of CH1, CH2, CH3, and CH4 domains;

(c) the immunoglobulin Fc region further comprises a hinge region; or

(d) the immunoglobulin Fc region is an immunoglobulin Fc fragment derived from IgG, IgA, IgD, IgE, or IgM.

19. The method of claim 18 , wherein:

(a) each domain of the immunoglobulin Fc fragment is a hybrid of domains, in which each domain has a different origin derived from immunoglobulins selected from the group consisting of IgG, IgA, IgD, IgE, and IgM;

(b) the immunoglobulin Fc fragment is a dimer or multimer consisting of single chain immunoglobulins comprising domains having the same origin;

(c) the immunoglobulin Fc fragment is an IgG4 Fc fragment; or

(d) the immunoglobulin Fc fragment is a human aglycosylated IgG4 Fc fragment.

20. The method of claim 19 , wherein:

(a) the non-peptidyl polymer is selected from the group consisting of polyethylene glycol, polypropylene glycol, an ethylene glycol-propylene glycol copolymer, polyoxyethylated polyol, polyvinyl alcohol, polysaccharide, dextran, polyvinyl ethyl ether, a biodegradable polymer, a lipid polymer, chitin, hyaluronic acid, and a combination thereof; or

(b) the non-peptidyl polymer is polyethylene glycol.

21. The method of claim 20 , wherein the polyethylene glycol has a molecular weight of 3.4 kDa.

22. The method of claim 1 , wherein the protein complex is administered to the patient within 30 minutes, 2 hours, 3 hours, 5 hours, 8 hours, or 12 hours of completion of the chemotherapeutic regimen.