Jazz Pharmaceuticals has won US Food and Drug Administration (FDA) approval for its cancer drug Ziihera. The approval raised the drug's projected peak sales range. Separately, chief commercial officer Samantha Pearce plans to retire by June 30, 2027, or when a successor is appointed. Jazz has started an internal and external search. In its second-quarter 2026 update, Jazz reported revenue of $1,208.3 million and raised full-year 2026 guidance to $4.60–4.75 billion. The share price still fell 7.6% after earnings. Simply Wall St's narrative projects revenue of $5.7 billion and earnings of $1.7 billion by 2029, implying a fair value of $294.27 a share.

Jazz Pharmaceuticals reported its oncology revenue surpassed $1 billion in 2025, marking a 32% year-over-year increase. The growth follows three recent product launches, including zanidatamab, Modeyso and Zepzelca's FORTE regimen. The company raised zanidatamab's estimated peak-sales opportunity to $3 billion-$5 billion. Jazz aims to increase HER2-directed treatment adoption in gastroesophageal cancer, where only 60% of eligible HER2-positive patients currently receive such therapy. Jazz estimates the US incidence of HER2-positive gastroesophageal adenocarcinoma at approximately 8,000 patients, with a labelled population of 3,000 to 4,000 patients. The company is also developing zanidatamab for biliary tract cancer, colorectal cancer, non-small cell lung cancer and breast cancer. Jazz maintains commercial investment whilst preserving financial flexibility for acquisitions across oncology, epilepsy and sleep disorders.

Jazz Pharmaceuticals' stock has risen 29.7% over the past six months, outpacing the S&P 500 by 17 percentage points to reach $240.49 per share. However, analysts point to concerning trends in the company's fundamentals. The company's adjusted operating margin has declined by 2.6 percentage points over five years, despite revenue growth that should have improved economies of scale. Its trailing 12-month adjusted operating margin stood at 41.7%. Additionally, Jazz Pharmaceuticals' five-year average return on invested capital was just 2.7%, below the typical cost of capital for healthcare companies. This suggests mediocre efficiency in deploying capital for growth. The stock currently trades at 9.6× forward price-to-earnings ratio. Analysts consider this valuation reasonable but believe the company's weakening fundamentals present downside risk.