True about the orphan drug is:
Orphan Drugs are drugs or biological products for diagnosis/treatment/prevention of a rare disease or condition, or a more common disease (endemic only in resource-poor countries) for which there is no reasonable expectation that the cost of developing and marketing it will be recovered from the sales of that drug.
The list includes sodium nitrite, fomepizole, liposomal amphotericin B, ancrod, rifabutin, succimer, somatropin, digoxin immune Fab (digoxin antibody), liothyronine (T3) and many more.
Developed for orphans
Drugs used very rarely
Drugs used for rare diseases
Rare drug for common diseases