Remove Duplicates within a cell?

[HM]

Hi,

I've summarised my data using concat because I want to keep all unique values but it also repeats duplicates - is there any way to remove duplicates within a cell? 

For example: change "A,A,A,B,B,C,D,E" to "A,B,C,D,E"?

Thanks

[yzhang]

This is some impressive skill...

[htalteryx]

How do I separate if the values need to be separated from:

Smith, Jane;Smith, Jane;Smith, Jane;Doe, John;Doe, John;Smith, Joanna;Smith, Joanna;Smith, Joanna;Smith, Joanna;Smith, Jane

to:

Smith, Jane;Doe, John;Smith, Joanna

__

Thank you!