OBJECTIVES: Oral antidiabetics(OAD) have comparable safety and efficacy in fixed-dose combination therapies(FDCT) and loose-pill combination therapies(LPCT) for patients with Diabetes Mellitus Type II(T2DM). To evaluate FDCT outcomes besides safety and efficacy a systematic review was conducted. METHODS: Searches of Medline/Embase databases from 1998-2009 used predefined search terms: “fixed-dose combination”, “loose-dose combination” and “diabetes”. Additionally, we reviewed abstracts from ISPOR, EASD and ADA meetings. T2DM studies were included if they reported adherence, patient reported outcomes(PRO), costs, resource use or cost-effectiveness. RESULTS: Seventeen studies met the search criteria.  Seven studies reported adherence. Adherence was 10-13% higher for FDCT than LPCT in patients starting combination therapy(two studies).  Adherence decreased 1.5% and 10.0% when switching from monotherapy to combination therapy for FDCT and LPCT, respectively(one study, P<0.001).  Three studies report adherence when switching from LPCT to FDCT versus remaining on LPCT.  Switching to FDCT increased adherence 3.5%-12.4%, while remaining on LPCT changed adherence -1.5% to 5.0%(P<0.005).  For patients newly initiating OAD medication, one study found no adherence advantage for FDCT, compared with monotherapy or LPCT. Five randomized controlled trials(RCTs) reported treatment satisfaction. Four publications found patients preferred FDCT using the Diabetes Treatment Satisfaction Questionnaire(DTSQ). One publication found improved satisfaction for one DTSQ subscale only. Five abstracts reported economic outcomes. Two abstracts determined patients on FDCT use fewer healthcare resources and decreased direct healthcare costs by $169 and $255 patient per month than LPCT(P<0.05). Two cost effectiveness models determined clinical benefits from clinical trials translate into cost savings and increased life expectancy. One budget impact model reported minimal budget impact. CONCLUSIONS: Compared to T2DM patients on LPCT, FDCT users may have better adherence, improved satisfaction, and lower direct medical costs. Overall, data for economic implications are limited. Further studies are warranted to further define potential benefit of FDCT in T2DM, a prevalent and costly disease.