Celgene gets options to Prothena's tau, TDP-43 antibodies

Prothena Corp. plc (NASDAQ:PRTA) added $7.45 (22%) to $41.30 in after-hours trading after granting Celgene Corp. (NASDAQ:CELG) exclusive options to neurodegenerative disease antibodies against microtubule-associated protein tau (tau; MAPT; FTDP-17), TAR DNA binding protein 43 (TDP-43; TARDBP) and an undisclosed target. Prothena will receive $100 million up front and $50 million in an equity investment and is eligible for $562.5 million in milestones per program, plus exercise fees and royalties ranging from the high single digits to high teens.

Prothena said it has identified antibodies that can prevent misfolded tau from binding to cells, inhibit cell-to-cell transmission and block downstream toxicity. The company also said it is performing in vitro screening for TDP-43-targeted antibodies. Prothena declined to provide details, and Celgene did not respond to inquiries...