The price tag for Novartis’ newly approved and seemingly miraculous gene therapy for a rare childhood disease presents a whole new challenge of its own.

Zolgensma (onasemnogene abeparvovec-xioi) is the first systemic gene replacement therapy ever to win the FDA’s approval. It’s also the world’s most expensive medicine, at more than $2.1 million for a 60-minute intravenous injection.

Zolgensma arrives just as lawmakers in Washington, D.C. are joining the chorus of critics who say that drug prices are too high. Several bills are working their way through Congress, and rules are pending in HHS, that proponents say will tackle the seeming paradox—magic pills are doing more and more, but for fewer and fewer people.