Keep in mind that if there's a \w character in the middle of the binary data, that won't work:

$ perl|od -tx1
my $c=65.66.20.21.67.23.25.10;
$c =~ s/\W+$//;
print "$c\n";
__OUTPUT__
0000000 41 42 14 15 43 0a
0000006
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Note that the two bytes (14 and 15) between "B" (42) and "C" (43) are still there.