Doubt on RegEx

Shell Programming and Scripting
1

Friends,

I have a silly doubt:

Assume that I have a line like this

Heading: Value1; SomeText1 (a, b, c), Value 2; SomeText2 (d, e, f)

I wanted to remove all semicolon and remove everything in brackets (including brackets). I managed to do this using this code

if (strstr($line,'Heading')){
                $new_heading = str_replace(";", "", $line); // Replaces semi-colon
                $new_heading = preg_replace("/\([^\)]+\)/","",$new_heading); //Removes Text With in Brackets
                $line = $new_heading;
                echo $line; //Outputs "Heading: Value1 SomeText1 , Value 2 SomeText2"
                }

Now Assume I have a line like this

Heading: Text1 (a, b) Text2. (d, f) Text3 (g, h)

What I want to achieve is... Remove everything with in brackets (inclusive brackets) and replace it with comma. However the last ocurance of the bracket should not be replace with a a comma.

I mean the output should be

Heading: Text1 , Text2. , Text3

How to achive this?

2 
<?php

$heading = "Heading: Text1 (a, b) Text2. (d, f) Text3 (g, h)";
$new_heading = rtrim(preg_replace("/\([^\)]+\)/",",",$heading),',');
echo $new_heading;

?>