I could think of:
- Stoicism, say in Seneca who sees pleasures as "low, slavish, perishable", contrasting pleasures with virtue, which he sees as the highest good. Seneca argues that one who pursues virtue is likely to find happiness, but that happiness should only be seen as a benefit of virtue, and not as an aim by itself.
- Maybe one could also mention catholicism, which viewed amusements with contempt, and in general sensual pleasures as a tool of Satan to distract us from righteous path, an attitude exemplified in the excommunication of actors.
But I wouldn't qualify those as modern. And this brings me to my question: which philosophers, say in the last couple of hundred years, have developed ideas around a distrust of happiness and pleasures, and put those ideas at the center of their philosophy?