Lilly shares slide as Foundayo prescriptions lag expectations, while Novo's Wegovy gains momentum

Eli Lilly's stock fell nearly 5% after the latest weekly prescription count for its obesity drug Foundayo missed analysts' expectations.

IQVIA data showed U.S. prescriptions for Foundayo reached 3,707 for the week ending April 17, up from 1,390 in its first two days, but still lagged behind Novo Nordisk's Wegovy, which recorded 3,071 prescriptions in its first full week and rose to 18,410 the following week.

Analysts had once projected up to $5 billion in 2026 sales for Foundayo; the weaker uptake has prompted a downgrade to a $1.3-$1.5 billion range, a level that would require about 300,000 prescriptions by year-end.