Mass-balance Study of [14C]-APD421 in Healthy Volunteers

Inclusion Criteria: * Healthy males * Age 18 to 65 years of age at time of signing informed consent * Body mass index (BMI) of 18 to 30 kg/m2 or, if outside the range, considered not clinically significant by the investigator * Must be willing and able to communicate and participate in the whole study * Must provide written informed consent * Must agree to use an adequate method of contraception (as defined in Section 8.4) * Must have regular bowel movements (ie average stool production of ≥1 and ≤3 stools per day) Exclusion Criteria: * Prior participation in another study with a radiation burden of \> 0.1 mSv and ≤ 1 mSv in the period of 1 year prior to screening; a radiation burden of \> 1 mSv and ≤ 2 mSv in the period of 2 years prior to screening; a radiation burden of \> 2 mSv and ≤ 3 mSv in the period of 3 years prior to screening, etc (add 1 year per 1 mSv)