Evaluating the Safety and Plasma Levels of N-Methanocarbathymidine (N-MCT) in Normal Patients

Patients will receive 200 mg, 400 mg, 800 mg or 1200 mg of N-Methanocarbathymidine administered orally on day 1 after subject's full screen for each cohort. Each dose will be completely evaluated for safety and pharmacokinetics. The doses of each cohort will be given after complete evaluation of the preceding cohort for any sign of toxicity. In the absence of no observed toxicity, the next cohort will be started in the normal subjects.

Two patients in Cohort 3 \& 4 will receive placebo capsules which is mannitol filled into size 0 capsules.