The classic Seinfeld Bubble Boy episode may have been funny but for children with deficiencies in their immune system like those with SCID or "bubble boy" disease there is a real risk of dying from common infections. Now there is news that a treatment could cure people of the problem that causes this condition.
This is the case of work being done against an orphan illness. In other words a condition where there is not a great deal of money to be made. But, for the person with the condition it is the only one that matters.