Amgen Stock Tumbles 9% After Novartis Trial Failure Raises Lp(a) Concerns

Amgen's stock price plummeted by nearly 9% on September 8 to $397.77, marking one of its worst single-day declines in recent years. The decline came after Novartis' Phase 3 trial for its cholesterol-lowering drug pelacarsen failed to show a reduction in cardiovascular events despite lowering Lp(a) levels in the blood.

The failure of pelacarsen has raised concerns about the entire Lp(a) drug class, including Amgen's own experimental cholesterol drug olpasiran. Olpasiran targets the same biological pathway as pelacarsen but through a different mechanism, and its Phase 2 study showed that it reduced Lp(a) levels by more than 90%.

However, with Novartis' trial failure now casting doubt on the effectiveness of lowering Lp(a) levels in reducing cardiovascular risk, Amgen's investors are left wondering whether a 90% reduction in Phase 2 will translate to an eventual Phase 3 trial outcome. BMO Capital Markets analyst Evan Seigerman downgraded Amgen to Market Perform from Outperform, citing more balanced risk-reward after the stock's 34% year-to-date advance.

Amgen's financial position remains strong, with revenue rising 10% year over year to over $10 billion in Q2 2026. However, the broader market provided little shelter for Amgen's decline, with the Dow Jones Industrial Average falling by 628 points on September 8 due to Brent crude surging towards $99 a barrel.