I personally wouldn't use regex for this, but here you go. The secret is to make your entire address string match optional with (?:REGEX HERE)? 
$_ = join '', <DATA>;
while (m/(.*)<br \/>\n(?:(.*)<br \/>\n)?(.*)<br \/><br \/>/g) {
    print "$1 - $2 - $3\n\n";
}

__DATA__
Name<br />
Address<br />
URL<br /><br />
Name2<br />
Address2<br /><br />

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In reply to Re: Regexp with optional group containing backreference by TedPride
in thread Regexp with optional group containing backreference by knewter

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