A clot to consider

The decision by Biogen Inc. (NASDAQ:BIIB) to spin off its hemophilia business is eliciting mixed reactions. At least one investor and an analyst are questioning the timing and reasons for the split, while another buysider thinks it makes sense to part with assets that are growing but face looming competition.

The spinout will house Biogen's fastest-growing sources of revenue, Eloctate efmoroctocog alfa for hemophilia A and Alprolix eftrenonacog alfa for hemophilia B, and a pipeline of preclinical programs. The drugs posted 1Q16 sales of $183 million, up 89% from $97 million in 1Q15...