- Current or recent history (in the last 2 years) of abuse or addiction (tobacco, alcohol, drugs or substances), or weekly alcohol intake of more than 21 units, or a positive alcohol breath test or urine drug screen at Screening or Baseline. One unit is equivalent to a ½ pint (280 mL) of beer, 1 measure (25 mL) of spirits or 1 small glass (125 mL) of wine.