You still didn't specify what data you need from the line. If you really just want to split on the commans, you can use Text::Balanced.

use strict;
use warnings;

use Text::Balanced qw( extract_bracketed extract_multiple );

while (<DATA>) {
    chomp;

    print("\n") if $. != 1;

    my @extracted = extract_multiple($_, [
        ',',
        \&extract_bracketed,
    ]);

    my @pieces;
    push @pieces, '' if @extracted;
    for (@extracted) {
        if ($_ eq ',') {
           push @pieces, '';
        } else {
           $pieces[-1] .= $_;
        }
    }

    print("$_\n") for @pieces;
}


__DATA__
<*2>FOO<2,1>,<*3>(SigB<8:0:2>,BAR),<*2>Siga<2:0>,Sigb<8,7,6,5,0>
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