But I wouldn’t call the disease “cured”.

That's probably why they use the word "curable"

But that is cureable, just not guaranteed. You are more likely to live than die with this treatment.

Or cure just mean for the people which it works for, they are cured. Contrast with medicines slowing down the effects such as HIV medicine.

In other words, cure is probably the right word, just not for everybody.

Particularly if I was in the 30% that still dies from it.

Although if I were to die from it I wouldn't probably be able to call it anything.