Arcus Biosciences (RCUS) entered late 2025 with growing optimism around its oncology pipeline, supported by encouraging clinical data, multiple upcoming catalysts, and a balance sheet strong enough to fund years of development. For a time, the company looked like a high-upside growth stock.
However, that story was put to the test in December, when Arcus announced the cancellation of its Phase 3 STAR-221 research due to inefficiency. While the stock is up 49% year-to-date (YTD), it has plunged 16% from its 52-week high of $26.40. So, has this setback weakened the investment case for Arcus, or does it signal that Arcus' path forward has been sharpened? Here’s how investors should think about the stock now.
