I am currently working with strings that follow this format:
 [Matt, Hopkins] [MI] [5.75] [Wood] and so forth.
Using regex might just make things harder for yourself here.
This looks like CSV data. You can use a CSV library to correctly parse this into individual fields (*):
String fields = YourCsvLibrary.parseRow(string); // or string.split(","), maybe.
and then recombine the fields as appropriate. For example, your regex's logic can be expressed via the following code:
String output = Arrays.copyOfRange(fields, 1, fields.length); output = fields; output = fields + "," + fields;
String.split(",") might work, provided the field data doesn't contain quotes, commas, newlines, etc.