<?php

$str = "Go Forty Go (IRE) 471    -> Go Forty Go";
$str2 = "Pearl Noir 15528258 D3   -> Pearl Noir";
$str3 = "Synonym (ITY) 1793158-00 D1   -> Synonym";
preg_match('/^.*?(?=\s*[^\s\p{L}])/', $str, $match);
echo $match[0] . PHP_EOL;
preg_match('/^.*?(?=\s*[^\s\p{L}])/', $str2, $match1);
echo $match1[0] . PHP_EOL;
preg_match('/^.*?(?=\s*[^\s\p{L}])/', $str3, $match2);
echo $match2[0] . PHP_EOL;