#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)[^;]*(\((?>[^()]+|(?1))*\))(*SKIP)(*F)|;"
Local $sString = "Almonds ; Roasted Peanuts (Peanuts; Canola Oil (Antioxidants (319; 320)); Salt); Cashews " & @CRLF & _
"Peanuts (32.5%); Macadamia Nuts (14%; PPPG(AHA)); Hazelnuts (9%); nuts(98%)"
Local $sSubst = ","
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm