PRAX (Top Pick): Elsunersen Wins FDA Breakthrough Designation in SCN2A-DEE — An Underappreciated Asset Overlooked By the Street

Research evidence excerpt

PRAX (Top Pick): Elsunersen Wins FDA Breakthrough Designation in SCN2A-DEE — An Underappreciated Asset Overlooked By the Street

FLASH NOTE

June 22, 2026

Yatin Suneja yatin.suneja@guggenheimpartners.com PRAX (Top Pick): Elsunersen Wins FDA

212 518 9565 Breakthrough Designation in SCN2A-DEE — An

Eddie Hickman, Ph.D.

eddie.hickman@guggenheimpartners.com Underappreciated Asset Overlooked By the Street

212 518 9904

Delma Caiati, M.D., Ph.D. Key Message: PRAX received FDA Breakthrough Therapy Designation (BTD) for

delma.caiati@guggenheimpartners.com elsunersen, its ASO for seizures associated with SCN2A-DEE caused by gain-of-function 617 859 4606

variants. This is the third BTD across the company's late-stage pipeline, which we view

Min Lee, Ph.D. as a meaningful Solidus platform validation event. The designation was supported by

min.lee@guggenheimpartners.com the previously reported EMBRAVE Part A data, which showed a 77% sham-adjusted

212 823 6744 reduction in monthly seizures (p=0.015), with 71% of treated patients achieving >50%

Iris Gao, Ph.D. seizure reduction, 57% achieving at least a 28-day seizure-free period, and benefits

iris.gao@guggenheimpartners.com sustained in the open-label extension for up to one year. Elsunersen now carries BTD,

212 518 9013 Orphan Drug, and Rare Pediatric Disease designations from the FDA, and Orphan

Drug and PRIME designations from the EMA; the Rare Pediatric Disease designation

preserves potential eligibility for a PRV at approval, which carries standalone monetizable

PRAX valuethe FDA(~$200MM).disclosed Thein Decemberpivotal EMBRAVE32025, whichstudyshouldis enrollingacceleratefollowingthe pathalignmentto filing;withwe

Praxis Precision Medicines, Inc. anticipate data in 2027. Assuming ASO pricing applied to the addressable SCN2A-