Critical Steps

5,000 to 10,000 Compounds Yield 1 New Drug to Market
Step	Number of Compounds	Years
Step	Number of Compounds	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
Discovery – identifying and screening	5,000—10,000
Preclinical Testing – in laboratory and animal studies	250
Phase I – Clinical Testing. Safety and dosage evaluated on 20-100 healthy human volunteers	5
Phase II – Clinical Testing. Efficacy and side effects tested on 100-500 patient volunteers	1
Phase III – Clinical Testing. Effectiveness and reactions to long-term use tested on 1,000 to 5,000 patient volunteers	1
FDA Review and Approval	1