Merck KgaA's Stock Plummets on Earnings Miss and Patent Concerns

Merck KGaA's stock price has plummeted due to a sharp 30% earnings-per-share miss and a squeeze in profit margins down to 9%, indicating weaker underlying profitability than expected.

The company's cautious outlook for 2026 and mounting generic competition for its key multiple sclerosis drug Mavenclad have further damaged sentiment, signaling slower growth for the rest of the fiscal year.

However, Definium Therapeutics' late-stage pipeline with several major trial results on the horizon could eventually reshape its regulatory prospects and attract partners, offering a clearer path to commercialization.