Key takes from SAN/REGN alliance expansion call. Is Sanofi paying up to $8bn for dosing convenience only?

Citi's take on Sanofi SA (SASY.PA). While the call on Sanofi/REGN's announced alliance expansion to include 4 new PI/preclinical potential Dupixent successors provided incremental colour on milestone timing and deal terms, we thought it was somewhat disappointing given: (1) The target profiles of the molecules focus solely on increasing dosing interval (lead IL-13 Q3M-Q6M) without compromising efficacy or tolerability with no expectation for improving efficacy, suggesting a potentially weaker profile vs Pfizer's anti-IL13xIL4xTSLP trispecific tilrekimig and AbbVie's LA anti-IL13 zumilokibart, both of which have shown potential for better efficacy in PII, and the latter for Q3M-Q6M dosing, plus potential challenges in obtaining reimbursement if launching post-Dupixent biosimilar launch. (2) REGN was dismissive of the ability of any other MoA to exceed Dupixent efficacy without hampering safety, suggesting a high bar for additional acquired assets or Sanofi's lunsekimig or its STAT-6s to