A Clinical Trial of CoFactor Formulations and Leucovorin Administered Intravenously in Healthy, Adult Subjects.

Inclusion Criteria: * Males and Females age 18-65 inclusive at screening. * Subject has to agree to practice abstinence or medically accepted contraception and not to participate in sperm donation or in vitro fertilization. * Body Mass Index in the range of 18 to 30 kg/m2 and body weight of 45 to 95 kg. * Subject must be healthy as determined by the investigator on the basis of screening evaluations. * Subject must be nonsmoker or smoker of fewer than 10 cigarettes per day as determined by history. Must be able to abstain from smoking during the in-clinic stay. Exclusion Criteria: * Presence of clinically significant illness within 21 days prior to dosing, viral or bacterial infection, or documented drug allergies that may affect subject's safety during the study. * Laboratory or clinical evidence suggestive of disease. * Clinically significant or predisposing disorder that may interfere with the absorption, distribution, metabolism and/or excretion of drugs. * History of drug abuse within 1 year of dosing and/or admitted alcohol abuse or history of alcohol use that may interfere with the ability to comply. * Pregnant, lactating, or positive pregnancy test. * Clinically significant electrocardiogram abnormalities. * History of positive test for hepatitis B or C, or HIV. * Positive findings of urine narcotic screen. * History of drug allergy.