After an adequate screening period (Day -7 to -1), all eligible patients of the first dosing cohort will receive the initial, low dose of VLX103 150 mg per day (QD) for 14 consecutive days. Subjects will be evaluated only for safety, pharmacodynamics and pharmacokinetics during this period. Pre-established safety criteria will be used to decide upon dose escalation, for each subject. If patients tolerate well VLX103 at 150 mg QD , a second cohort will then receive a 300 mg QD regimen for 14 days. At the end of this period, safety, pharmacodynamics and pharmacokinetics will be assessed as well. The next dose will be 450 mg QD for 14 days, with the same monitoring process. Long term safety will also be assessed, at all 3 doses, at Day 30 and 90 post treatment initiation.