▁growth ▁factors ▁and ▁neur om edi ators ▁have ▁been ▁proposed . ▁Studies ▁were ▁conducted ▁on ▁top ical ▁treatment ▁with ▁Sub st ance ▁P ▁and ▁I G F - 1 ▁( ins ul in - like ▁growth ▁factor - 1 ), ▁demonstr ating ▁an ▁effect ▁on ▁ep ith el ial ▁he aling . ▁N erve ▁G row th ▁F actor ▁( NG F ) ▁play ▁a ▁role ▁in ▁the ▁ep ith el ial ▁pro l ifer ation ▁and ▁different iation ▁and ▁in ▁the ▁surv ival ▁of ▁cor ne al ▁sens ory ▁n erves . ▁Top ical ▁treatment ▁with ▁mur ine ▁N G F ▁showed ▁to ▁promote ▁recovery ▁of ▁ep ith el ial ▁integrity ▁and ▁cor ne al ▁sens itivity ▁in ▁NK ▁patients . ▁Rec ently , ▁a ▁recom bin ant ▁human ▁n erve ▁growth ▁factor ▁eye ▁drop ▁form ulation ▁has ▁been ▁developed ▁for ▁clin ical ▁use . ▁ ▁C en eg erm in , ▁a ▁recom bin ant ▁form ▁of ▁human ▁N G F , ▁has ▁recently ▁been ▁approved ▁in ▁Europe ▁in ▁an ▁eye ▁drop ▁form ulation ▁for ▁ne uro t roph ic ▁ker at itis . ▁C en eg erm in ▁as ▁an ▁eye ▁drop ▁form ulation ▁for ▁treatment ▁of ▁NK ▁is ▁approved ▁by ▁F DA ▁in ▁August ▁ 2 0 1 8 ▁ ▁See ▁also ▁▁ ▁Ker at itis ▁ ▁Cor nea ▁▁ ▁R are ▁disease ▁ ▁References ▁ ▁External ▁links ▁▁ ▁Category : Dis orders ▁of ▁s cl era ▁and ▁cor nea ▁Category : R are ▁dise ases <0x0A> </s> ▁D