It depends on your definition of AI, and 'cure', and to what degree you credit the AI with a human operator.

If you mean in the truest sense, "An artificial intelligence autonomously discovered & validated a cure", then none. Because artificial intelligence does not exist. If you mean "A language calculator (llms) autonomously discovered and validated a cure", then also none. If you mean the weaker version of "An LLM supported research leading to cures", then lots. But did the humans do that? If I build a house with a hammer, did the hammer build the house? If you mean the even weaker version of "Data modeling coalesced data which discovered patterns at a scale humans never could on their own which lead to cures", then nearly every cure in the last 30 years.

It's one of those things that gets more complicated the closer you look.