Sed help with replace

Shell Programming and Scripting
1

phx,v3apilw2core,app-usage,05-03-2010, phx,tr(white,wavern), 2,1

I need help with the sed command to remove the text in red from the line above, including braces.

I tried the following two approaches:-
sed '/(/,/)/ !d' test.txt | more

sed "/(/,/)/ !d" test.txt | more

2 
$ echo 'phx,v3apilw2core,app-usage,05-03-2010, phx,tr(white,wavern), 2,1' | sed "s/(.*)//"    
phx,v3apilw2core,app-usage,05-03-2010, phx,tr, 2,1