Diabetes Prevention Program Outcomes Study

The Diabetes Prevention Program (DPP) was a multi-center trial examining the ability of an
intensive lifestyle or metformin to prevent or delay the development of diabetes in a high
risk population due to the presence of impaired glucose tolerance (IGT). The DPP has ended
early demonstrating that lifestyle reduced diabetes onset by 58% and metformin reduced
diabetes onset by 31%.

DPPOS (2002-2013) is designed to take advantage of the scientifically and clinically valuable
DPP participants. This group of participants is nearly 50% minority and represents the
largest IFG/IGT population ever studied. Clinically important research questions remain that
focus on 1) durability of the prior DPP intervention, 2) determination of the clinical course
of precisely known new onset diabetes, in particular regarding microvascular disease, CVD
risk factors and atherosclerosis, 3) close examination of these topics in men vs women and in
minority populations.

The major aims of DPPOS-3 (2014-2025) take advantage of the long-term randomized exposure of
the study cohort to metformin and the aging of the DPPOS cohort. The metformin exposure and
high degree of study retention and adherence (~85% of the DPPOS cohort continues to attend
annual and mid-year visits) allows DPPOS-3 to examine the long-term effects of metformin on
cardiovascular disease (CVD) and cancer outcomes, outcomes of great clinical interest and
import.