David Cossman has been battling cancer for eight years . He agreed to clinical trials to stay alive after regular treatment finally ran out . He underwent his fourth clinical trial this year ; he 's one of 16 people in the study . Fighting on . Before FDA approval , a drug goes through extensive testing .
David Cossman has been battling cancer for eight years . He agreed to clinical trials to stay alive after regular treatment finally ran out . He underwent his fourth clinical trial this year ; he 's one of 16 people in the study . Before FDA approval , a drug goes through extensive testing .