Piper Jaffray analyst Christopher Raymond said he remains a "steadfast" bull on Alexion (ALXN) and would be a buyer of the shares amid the weakness today following Regeneron's (REGN) announcement of topline data from the pozelimab Phase 2 clinical program in paroxysmal nocturnal hemoglobinuria, or PNH. While six patients is "a fairly meaningful sample size" in this indication, Raymond said that "many questions remain," including patient baseline characteristics and patient specific data. It is difficult to compare the data to Soliris/Ultomiris without having more insight, added Raymond, who said he thinks "investors would do well to take a few steps back before reacting" to today's pozelimab release. The analyst, who prefers to wait for "a more fulsome update" before jumping to any conclusions, views today's stock reaction as overblown and he keeps an Overweight rating on Alexion shares, which are down 7% in afternoon trading.

Oppenheimer analyst Hartaj Singh raised the firm's price target on Regeneron to $1,175 from $1,125 and keeps an Outperform rating on the shares ahead of the Q1 earnings report on May 2. Oppenheimer believes the areas of focus will be the status and dynamics of the Eylea High Dose launch, questions around the impending Dupixent COPD PDUFA, the status of the two oncology approvals expected in 2024, updates on various pipeline projects in immunology and oncology, and comments on capital allocation and financial planning by the new CFO at the company.