OBJECTIVES: To measure the extent to which closing the coverage gap will affect drug utilization, access, and OOP spending among seniors with chronic diseases, including respiratory diseases (asthma or COPD), hypertension, hyperlipidemia, psychosis, depression, and diabetes. METHODS: A difference-in-difference-in-difference (DDD) analysis from 2008 to 2012 was used. RESULTS: The Medical Expenditure Panel Survey data files from 2008 to 2012 imply that closing the coverage gap had no significant impact on the disparities in annual drug expenditures, OOP spending, and total number of prescriptions between minorities and whites. However, it significantly increased the disparity in access to prescriptions between minorities and whites by 3.8 percent. When teasing out the effect by race, the results show that closing the coverage gap had no significant impact on the disparities in OOP spending and total number of prescriptions between African-Americans and whites, while it significantly increased the disparity in access to prescriptions for by 7.3 percent, and significantly decreased the disparity in annual drug expenditures by $1,162. Regarding Hispanics, it significantly increased the disparities in OOP spending and total number of prescription drugs by $325 and 8 prescriptions, respectively. However, it had no significant impact on the disparities in annual drug expenditures and access to prescriptions. CONCLUSIONS: The findings of this study demonstrate that the benefits of closing the coverage gap are disproportionately distributed among different racial groups. Closing the coverage gap decreased disparities in annual drug expenditures, OOP spending, and access to prescription drugs for African-American compared to white, while It increased disparities in annual drug expenditures, OOP spending, and total number of prescription for Hispanics compared to whites.