Stock Watch: Thoroughly Moderna Missteps

Investors in companies like Pfizer Inc.* and Roche Holding AG have discovered that developing vaccines, drugs and diagnostics that helped resolve the pandemic has been a double-edged sword. For example, Pfizer’s stock price rose by about 45% between mid-2019 and the end of 2021 when the clinical and commercial successes of its antiviral Paxlovid (nirmatrelvir/ritonavir) to treat COVID-19 and its mRNA vaccine to prevent it – Comirnaty – dominated the company’s investment proposition. After Paxlovid and Comirnaty sales peaked in 2022, Pfizer’s business returned to a more sedate pace. In consequence, Pfizer’s stock price has almost halved since the December 2021 peak as unfavorable revenue comparisons continually remind investors of its pandemic heyday.

A slightly different dynamic was seen with the NASDAQ Biotech Index (NBI). Like Pfizer’s stock price, it rose by almost 70% from mid-2019 to its peak (earlier than Pfizer’s) in...