You can assign a Home page to a role, but as far as I know, not 'restrict' Home page access to a role. The safest thing to do is ensure that certain roles do not have access to certain reports that are going to be hosted in said Home page.
Not only can you restrict reports to roles, but you can also restrict tables to roles. When you click the 'settings' link while on the main home page of the application, select "Roles", then over to the right hand side, you will see the link "Set Role access to reports". Here you will have a grid presented where you can select which reports are available to which roles.
Open the properties of a particular role and use the "Permissions" and "User Interface" tabs to set role access to tables.