Why Is Skin Disorders Focused Acelyrin Stock Trading Lower Today?

Acelyrin Inc SLRN announced topline results from Part B of a Phase 2b/3 trial evaluating izokibep for moderate-to-severe Hidradenitis Suppurativa (HS). 

Hidradenitis suppurativa, also called acne inversus, is a chronic inflammatory skin condition with lesions including deep-seated nodules and abscesses, draining tracts, and fibrotic scars. 

The primary endpoint of HiSCR75 at week 16 did not meet statistical significance. 

However, response rates for izokibep showed early HiSCR100 responses, a clear dose effect supported by both pharmacokinetic exposures and HiSCR responses favoring 160 mg weekly dosing, and no evidence of safety or tolerability limitation.

In the primary non-responder imputation (NRI) analysis of Part B, statistical significance was impacted by patients with HiSCR75-100 discontinuing as early as week four unrelated to adverse events. 

In addition, there was a marked increase in placebo rates during the study. 

Applying a Last Observation Carried Forward (LOCF) sensitivity analysis of the full dataset highlighted the impact of responder discontinuations on the primary analysis and showed the statistical significance of HiSCR75 at week 16.

Price Action: SLRN shares are down 58.80% at $11.50 during the premarket session on the last check Tuesday.