How to remove trailing commas

Hi

I am using BODS 14.1.1.210.

I am trying to remove the trailing commas at the end but not remove the commas in between the string.

Eg

INPUT                             OUTPUT

240 V, 720W,,,,,,,,,          240 V, 720W

john, sam ,,,                    john, sam

sam, 24 years,,,,,,,,,,,,     sam, 24 years

Is there a function I can use to remove the commas at the right like rtrim_blank_ext used to trim blanks from right?

Cheers!!