▁a ▁rare ▁disease ▁or ▁condition , ▁which ▁is ▁one ▁that ▁affect s ▁less ▁than ▁ 2 0 0 , 0 0 0 ▁persons ▁in ▁the ▁United ▁States ." ▁In ▁the ▁European ▁Union ▁( E U ), ▁the ▁European ▁Medic ines ▁Agency ▁( EMA ) ▁defined ▁a ▁drug ▁as ▁" orph an " ▁if ▁it ▁is ▁intended ▁for ▁the ▁diagn osis , ▁prevent ion ▁or ▁treatment ▁of ▁a ▁life - th re aten ing ▁or ▁chron ically ▁and ▁seriously ▁deb il it ating ▁condition ▁affect ing ▁not ▁more ▁up ▁to ▁ 1 0 , 0 0 0 ▁EU ▁people . ▁E MA ▁also ▁qualified ▁an ▁or phan ▁drug ▁that ▁– ▁without ▁in cent ives ▁– ▁it ▁would ▁be ▁unlikely ▁that ▁market ing ▁the ▁drug ▁in ▁the ▁EU ▁would ▁generate ▁sufficient ▁benefit ▁for ▁the ▁affected ▁people ▁and ▁for ▁the ▁drug ▁manufact urer ▁to ▁justify ▁the ▁invest ment . ▁As ▁of ▁ 2 0 1 7 , ▁there ▁was ▁no ▁official ▁integration ▁of ▁the ▁or phan ▁drug ▁programs ▁between ▁the ▁F DA ▁and ▁E MA . ▁ ▁Global ▁statistics ▁, ▁there ▁were ▁ 2 8 1 ▁market ed ▁or phan ▁dru gs ▁and ▁more ▁than ▁ 4 0 0 ▁or phan - design ated ▁dru gs ▁in ▁clin ical ▁tri als . ▁More ▁than ▁ 6 0 % ▁of ▁or phan ▁dru gs ▁were ▁bi olog ics . ▁The ▁U . S . ▁domin ated ▁development ▁of ▁or phan ▁dru gs , ▁with ▁more ▁than ▁ 3 0 0 ▁in ▁clin ical ▁tri als , ▁followed