** Oppenheimer initiates coverage on Spruce Biosciences SPRB.O with "outperform" rating and $283 PT

** PT implies 241.7% upside to stock's last close

** Brokerage expects U.S. accelerated approval next year for SPRB's experimental drug tralesinidase alfa (TA-ERT) to treat Sanfilippo type B syndrome, a terminal, ultra-rare neurodegenerative disorder with no approved treatments

** Oppenheimer pegs initial global sales opportunity at more than $130 million for TA-ERT, which it views as a first-in-class, disease-modifying enzyme replacement therapy

** Says it views BioMarin BMRN.O as logical acquirer of SPRB or TA-ERT as it will fit inside BMRN's portfolio "like a hand in a warm glove"

** TA-ERT is natural commercial add-on for BMRN's Brineura, prescribed for CLN2 disease, with minimal incremental infrastructure, brokerage says

** As of last close, SPRB stock up ~163% YTD

(Reporting by Padmanabhan Ananthan)

((Padmanabhan.Ananthan@thomsonreuters.com))