Concatenate visible cells, remove duplicates

  • TL;DR: I need a formula to concatenate visible cells, remove duplicates, and add a ", " in between values.

    I have a spreadsheet that I have macros filtering all the time and running data pulls.
    Row 3 holds formulas that pull specific metrics out of my data set in A6:S16627.
    Cell R3 calls a VBA script to run that concatenates visible cells, and returns a value with duplicates removed.
    For example, if the data was 100, 100, 101, 102, 101, it would return "100, 101, 102."

    Is this possible with formulas? I have a script that accomplishes this already, but the script can't update effectively within the sheet when filters change.

    Thanks in advance.