Piper Jaffray analyst Edward Tenthoff noted that at Momenta's (MNTA) R&D Day the company shared additional safety data for anti-FcRn antibody M281, disclosing that three subjects in the multiple ascending dose cohort of the Phase 1 study experienced CK elevation and terminated dosing. Also, a 25-30% reduction in serum albumin was reported across single and multiple dosing cohorts, said Tenthoff, who added that neither of these events were observed in Argenx's (ARGX) animal or healthy volunteer studies for efgartigimod. The analyst, who believes efgartigimod produces similar activity without compromising safety and sees the company as about two years ahead of Momenta, keeps an Overweight rating and $154 price target on Argenx shares.