▁by ▁Europe . ▁Can cer ▁treatment ▁was ▁the ▁indic ation ▁in ▁more ▁than ▁ 3 0 % ▁of ▁or phan ▁drug ▁tri als . ▁ ▁Number ▁of ▁or phan ▁dru gs ▁in ▁clin ical ▁tri als : ▁ 6 0 0 ▁ ▁Number ▁of ▁or phan ▁dru gs ▁in ▁Ph ase - 2 ▁Tri al : ▁ 2 3 1 ▁ ▁Number ▁of ▁or phan ▁dru gs ▁in ▁U . S . ▁clin ical ▁tri als : ▁ 3 5 0 ▁in ▁the ▁pipeline ▁from ▁research ▁until ▁registration ▁▁ ▁Key ▁Market : ▁US ▁( S ales ▁more ▁than ▁US $ 4 0 ▁billion ) ▁ ▁Effect ▁on ▁invest ment , ▁sales ▁and ▁profit ▁According ▁to ▁Thom son ▁Re ut ers ▁in ▁their ▁ 2 0 1 2 ▁publication ▁" The ▁Econom ic ▁Power ▁of ▁Or phan ▁Dru gs ," ▁there ▁has ▁been ▁increased ▁invest ment ▁in ▁or phan ▁drug ▁research ▁and ▁development , ▁partly ▁due ▁to ▁the ▁U . ▁S . ▁Or phan ▁D rug ▁Act ▁of ▁ 1 9 8 3 ▁( O DA ) ▁and ▁similar ▁acts ▁in ▁other ▁regions ▁of ▁the ▁world ▁driven ▁by ▁" high - profile ▁phil anth rop ic ▁fund ing ." ▁ ▁According ▁to ▁D rug ▁Disc overy ▁Today , ▁the ▁years ▁ 2 0 0 1 ▁to ▁ 2 0 1 1 ▁were ▁the ▁" most ▁product ive ▁period ▁in ▁the ▁history ▁of ▁or phan ▁drug ▁development , ▁in ▁terms ▁of ▁average ▁annual ▁or phan ▁drug ▁design ations ▁and ▁or phan ▁drug ▁appro val s