# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/^([0-9]*)([A-Z]?),((?:(?!\sAPP|\sAPT).)*)(?:\sAPP|\sAPT)?(.*)$/$1,$2,$3,$4/mgi;t' <<< "5847A, rue Principal APP A
5847A, rue Prince Arthur APT 22
1111, Sherwood street"
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 SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html