Shares of Lantheus Holdings (LNTH) plummeted 31.47% in pre-market trading on Wednesday following the company's disappointing second-quarter results and reduced full-year guidance. The radiopharmaceutical-focused company faced headwinds from increased competition in the PSMA PET landscape, impacting its flagship product PYLARIFY.

Lantheus reported Q2 adjusted earnings of $1.57 per share, falling short of analysts' expectations of $1.67. Revenue for the quarter came in at $378 million, missing the consensus estimate of $389.1 million and representing a 4.1% year-over-year decline. The company's PYLARIFY sales, a key growth driver, decreased by 8.3% to $250.6 million due to heightened competition in the PSMA PET market.

In response to the challenging environment, Lantheus significantly lowered its full-year 2025 guidance. The company now expects revenue between $1.475 billion and $1.51 billion, down from the previous range of $1.55 billion to $1.59 billion. Adjusted earnings per share guidance was also reduced to $5.50-$5.70 from $6.60-$6.70. This substantial downward revision in outlook further contributed to the sharp decline in the stock price.