Hmm, now here's an interesting title to sink our teeth into: The Death Cure. The first two books of this series were named for pretty obvious reasons. The Maze Runner made sense because Thomas was a Runner in the Maze, and The Scorch Trials were simply the trials that the kids had to go through while in a wasteland called the Scorch. But The Death Cure is a little different. What is the death cure?
The title is almost oxymoronic (an oxymoron is a contradictory phrase, like "falsely true" or "frantically sane"). Death can't be cured—so in that sense, a "death cure" doesn't make much sense.
But in the context of the Maze Runner series, it seems as if WICKED is truly searching for some kind of cure that can prevent the death of the human race. So in this third book, that's what the focus is: the cure. But as we get to see, there never is a cure, meaning there can only be death.
At the same time, when we get to the end, the cure for the Flare seems to be—to let everyone who has it die off while those who are immune get to start over in paradise. So in that way, death really is the cure for the Flare. It will eventually be wiped out.
It seems as if WICKED's whole scheme has been to find a cure for death, which is their problem. Instead, they should have been searching for a way to help stop the spread of disease. A cure for the Flare was over their heads, and we get to see that up front and personal in this awfully terrific third book.