Use of ventricular enlargement rate in intravenous immunoglobulin treatment of Alzheimer's disease

1. A method for treating Alzheimer's disease in a subject in need thereof, comprising the sequential steps of:

(a) determining ventricular volume in the subject's brain by magnetic resonance imaging (MRI), thereby obtaining a baseline value of ventricular volume;

(b) administering an intravenous immunoglobulin (IVIG) composition to the subject for the purpose of treating Alzheimer's disease during a first time period;

(c) determining ventricular volume in the subject's brain by MRI, thereby obtaining a first intermediate value of ventricular volume;

(d) comparing the intermediate value from step (c) with the baseline value from step (a); and

(e) increasing administration of the IVIG composition in dose or frequency if step (d) indicates an increase from the baseline value to the first intermediate value and the increase is equal to or greater than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the first time period but without receiving treatment for the disease, wherein the expected increase in ventricular volume in a subject with Alzheimer's disease but without receiving treatment for the disease is defined as the amount of ventricular enlargement that would be anticipated during a given length of time in an Alzheimer patient not receiving anti-Alzheimer treatment, and

maintaining administration of the IVIG composition in dose or frequency if step (d) indicates no increase from the baseline value to the first intermediate value or indicates an increase that is less than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the first time period but without receiving treatment for the disease.

2. A method for treating Alzheimer's disease in a subject in need thereof, comprising the sequential steps of:

(a) determining ventricular volume in the subject's brain by magnetic resonance imaging (MRI), thereby obtaining a baseline value of ventricular volume;

(b) administering an intravenous immunoglobulin (IVIG) composition to the subject for the purpose of treating Alzheimer's disease during a first time period;

(c) determining ventricular volume in the subject's brain by MRI, thereby obtaining a first intermediate value of ventricular volume;

(d) comparing the intermediate value from step (c) with the baseline value from step (a);

(e) increasing administration of the IVIG composition in dose or frequency if step (d) indicates an increase from the baseline value to the first intermediate value and the increase is equal to or greater than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the first time period but without receiving treatment for the disease, and

maintaining administration of the IVIG composition in dose or frequency if step (d) indicates no increase from the baseline value to the first intermediate value or indicates an increase that is less than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the first time period but without receiving treatment for the disease;

(f) repeating steps (b) to (d) at least once and in each repeat comparing the latest intermediate value with the second latest intermediate value to determine future administration of the IVIG composition in the same manner as step (e).

3. The method of claim 1 , wherein step (d) during any repeat of step (f) indicates an increase from one intermediate value to its subsequent intermediate value and the increase is equal to or greater than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the time period between the two intermediate values but without receiving treatment for the disease, and the administration of the IVIG composition is increased in dose or frequency, further comprising the steps of:

(g) determining ventricular volume in the subject's brain by MRI after an additional time period during which the IVIG composition is administered to the subject, thereby obtaining additional intermediate value of ventricular volume;

(h) comparing the additional intermediate value with its previous intermediate value; and

(i) discontinuing further administration of the WIG composition if step (h) indicates an increase from the previous intermediate value to the additional intermediate value and the increase is equal to or greater than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the additional time period but without receiving treatment for the disease, and

maintaining administration of the IVIG composition in dose or frequency if step (h) indicates no increase from the previous intermediate value to the additional intermediate value or indicates an increase that is less than an expected increase in ventricular volume in a subject with Alzheimer's disease within a time period of the same duration as the additional time period but without receiving treatment for the disease.

4. The method of claim 1 , wherein the first time period is 3 months, 6 months, 9 months, 12 months, or 18 months.

5. The method of claim 2 , wherein the second or subsequent time period is 3 months, 6 months, 9 months, 12 months, or 18 months.

6. The method of claim 3 , wherein the second or subsequent time period is 3 months, 6 months, 9 months, 12 months, or 18 months.

7. The method of claim 1 , wherein the IVIG composition is administered at about 0.2 to 2 grams per kg body weight of the subject per month.

8. The method of claim 1 , wherein the IVIG composition is administered once a week, twice a week, once a month, or twice a month.

9. The method of claim 1 , wherein the IVIG composition is administered at about 0.4 gram per kg body weight of the subject twice a month.

10. A method for assessing efficacy of administration of an IVIG composition intended for treating Alzheimer's disease, comprising the steps of:

(a) determining the rate of change in ventricular volume of subjects suffering from Alzheimer's disease but without receiving treatment for the disease, thereby obtaining an average rate of change in ventricular volume as a non-therapeutic rate of ventricular volume change;

(b) determining the rate of change in ventricular volume of subjects suffering from Alzheimer's disease and receiving the IVIG composition, thereby obtaining an average rate of change in ventricular volume as a therapeutic rate of ventricular volume change; and

(c) comparing the therapeutic rate with the non-therapeutic rate, thereby determining the efficacy of the administration of the IVIG composition,

wherein the ventricular volume in steps (a) and (b) is determined by magnetic resonance imaging (MRI), and wherein the administration of the IVIG composition is deemed effective if the therapeutic rate is lower than the non-therapeutic rate, and the administration of the IVIG composition is deemed ineffective if the therapeutic rate is equal to or greater than the non-therapeutic rate.

11. The method of claim 10 , wherein the IVIG composition is administered at about 0.2 to 2 grams per kg body weight of the subject per month.

12. The method of claim 10 , wherein the IVIG composition is administered once a week, twice a week, once a month, or twice a month.

13. The method of claim 10 , wherein the IVIG composition is administered at about 0.4 gram per kg body weight of the subject twice a month.

14. The method of claim 10 , wherein the rate of change in ventricular volume in step (a) or (b) is determined over a time period of about 3 months, 6 months, 9 months, 12 months, or 18 months.

15. The method of claim 1 , wherein the IVIG composition is administered intravenously.

16. The method of claim 1 , wherein the IVIG composition is administered subcutaneously.

17. The method of claim 10 , wherein the IVIG composition is administered intravenously.

18. The method of claim 10 , wherein the IVIG composition is administered subcutaneously.