#!/usr/bin/perl -w
use strict;
use Text::Balanced qw (extract_bracketed);
my $text = "In (Madrid) (Spain";

my ($extracted, $remainder, $skipped);
my $newtext = "";
for (;;) {
   ($extracted, $remainder, $skipped) = extract_bracketed($text,'()','[^\(]*');
   if ($extracted) {
      $newtext .= $skipped;
      $newtext .= $extracted;
      $text = $remainder;
   } else {
      if ($@->{error} =~ /Unmatched opening/) {
         $remainder =~ s/\(/ /;
         $text = $remainder;
      } elsif ($@->{error} =~ /Did not find opening bracket/) {
         $newtext .= $remainder;
         last;
      } else {
         die "Unexpected text balance error: $@";
      }
   }
}

print "Now text is: *$newtext*\n";