Sarepta's gene therapy medicine kills patient, CEO suspends full year guidance

Safety Concerns & Regulatory Impact - Serepta's gene therapy Elevidys linked to two patient deaths due to liver failure in 15 and 16-year-old boys with Duchenne muscular dystrophy [1][2] - FDA initially approved Elevidys for 4 and 5-year-olds who could still walk, later expanding the label to nearly all Duchenne patients, a decision that proved controversial due to limited evidence of efficacy in older patients [3] - Serepta has halted shipments of Elevidys for more advanced patients while exploring a new safety regimen [4] Financial Performance & Projections - Serepta is suspending its 2025 guidance and will update its full-year revenue outlook when it announces the second quarter results [4] - Prior analyst projections estimated Elevidys sales of $1.5 billion for the year, but these projections are now in serious doubt [4][5] Market Reaction & Stock Performance - Serepta's stock (SPTO) is down approximately 48% today and about 85% over the last year [5] - Safety concerns may cause eligible patients to reconsider treatment decisions [5]