The method of claim 8 wherein about 350 μg to about 1000 μg of folic acid is administered.

The method of claim 9 wherein 350 μg to 600 μg of folic acid is administered.

An improved method for administering pemetrexed disodium to a patient in need of chemotherapeutic treatment, wherein the improvement comprises: a) administration of between about 350 μg and about 1000 μg of folic acid prior to the first administration of pemetrexed disodium; b) administration of about 500 μg to about 1500 μg of vitamin B12, prior to the first administration of pemetrexed disodium; and c) administration of pemetrexed disodium. view more

The method of claim 12 further comprising the administration of cisplatin to the patient.

The method of claim 12, wherein vitamin B12 is administered as an intramuscular injection of about 500 μg to about 1500 μg.

The method of claim 14, wherein vitamin B12 is administered as an intramuscular injection of about 1000 μg.

The method of claim 17 wherein 350 μg to 600 μg of folic acid is administered.

The method of claim 18 wherein folic acid is administered 1 to 3 weeks prior to the first administration of the pemetrexed disodium.

The method of claim 12, 18, or 19, wherein the vitamin B12 administration is repeated about every 6 to about every 12 weeks following the administration of vitamin B12 until administration of pemetrexed disodium is discontinued.

The method of claim 21 further comprising the administration of cisplatin to the patient.