An adaptive randomised, double-blind, single-centre, placebo-controlled Phase I study evaluating ECG effects, safety, tolerability and PK of single ascending doses of Modufolin® for Injection, 100 mg in healthy male volunteers. Thirty-three (33) eligible and consenting subjects will be included in 3 cohorts, 11 subjects in each cohort. Within each cohort, subjects will be randomised to receive either placebo (3 subjects) or Modufolin® for Injection, 100 mg (8 subjects). There will be 3 pre-defined ascending dose-levels. Additional dose levels may be considered if recommended by the internal Safety Review cCommittee. There will be an interval between each dose level to allow time for safety data to be analyzed and evaluated by the iSRC. The iSRC will have the choice to decide to escalate the dose as planned, reduce or increase the dose escalation step, repeat the dose, reduce the dose or terminate the study. The total study duration for the subjects will be approximately 5 weeks and there will be in total 3 visits to the clinic. Subjects will be screened for eligibility according to study-specific inclusion/exclusion criteria within 4 weeks prior to start of stud treatment (Visit 1; Screening visit). The subjects will be confined to the research clinic from the evening before dosing (Day -1) until 24 hrs post dose (Days 1 and 2). The subjects should be fasting overnight (8 hrs) before IMP/placebo administration until 4 hrs post-dose. A Follow-up Visit will be performed 5 to 10 days after dose administration of for each cohort.