Guardant Health Inc. shares surged 5.67% over the 24-hour period, driven by strong investor reaction to the company's second-quarter financial results that were released after the market close. The precision oncology company reported robust revenue growth and raised its full-year outlook, fueling the after-hours rally that anchored the day's gains.

The company posted Q2 revenue of $335 million, a 44% increase year-over-year and comfortably above the consensus estimate of $314.2 million. While adjusted loss per share of $0.42 slightly missed analyst expectations, investors focused on the top-line beat and the raised guidance. Guardant Health now expects full-year 2026 revenue between $1.34 billion and $1.36 billion, up from its prior forecast of $1.30 billion to $1.32 billion and above the FactSet consensus of $1.31 billion. Key growth drivers included a 38% rise in oncology revenue, fueled by a 63% increase in test volume, and a more than 250% jump in screening revenue, with Shield test volume reaching 66,000 during the quarter.

The upbeat results come amid a series of positive catalysts, including recent FDA approvals for Guardant360 Liquid CDx as a companion diagnostic for non-small cell lung cancer and the inclusion of the Shield blood test in American Cancer Society colorectal screening guidelines, both of which have expanded market opportunities and insurance coverage.