これまで興味がなかったって英語でなんて言うの？

"これまで興味がなかった"
- I didn't have any interest until now.
- I wasn't interested before.

「これまで野球に興味がなかったけど、好きになった。」
- I didn't have any interest in baseball until now. I've come to like it.
- I wasn't interested in baseball before, but I've come to like it.

この場合、次のような言い方ができますよ。

ーI never really liked baseball before but I like it now.
「前はあんまり野球が好きじゃなかったけど、好きになった」

ーI never had much interest in baseball until now, but I have started to enjoy it recently.
「今まであまり野球に興味がなかったが、最近好きになった」

ご参考まで！