Compass Therapeutics, Inc. (CMPX) just landed some serious Wall Street validation. William Blair initiated coverage on Monday with an Outperform rating, and the thesis centers on tovecimig, a DLL4xVEGF bispecific antibody that could reshape how doctors treat biliary tract cancer.

Here's what makes this interesting: bile duct cancer (also called biliary tract cancer or BTC) is a particularly nasty diagnosis with limited treatment options, especially after first-line therapies fail. Analyst Matt Phipps thinks tovecimig is positioned to become the new standard of care for second-line BTC patients, with clinical data likely surpassing what FOLFOX achieved in the ABC-06 trial.

The market opportunity is substantial. William Blair estimates about 15,000 patients in the U.S. alone would be eligible for tovecimig annually in this indication. That's a blockbuster-sized patient population, comparable to first-line metastatic melanoma or first-line metastatic head and neck cancer markets.

And the numbers look compelling. Phipps projects peak worldwide sales of $1.46 billion for tovecimig in BTC, which translates to a net present value of $9.84 per share for Compass.

But the story doesn't end with bile duct cancer. "We also believe there is proof of concept for DLL4xVEGF bispecifics in other indications, including ovarian cancer and colorectal cancer," Phipps wrote in his investor note Monday. That potential for label expansion adds another layer of upside.

William Blair isn't alone in its bullish stance. December 2025 saw a flurry of coverage initiations: Canaccord Genuity started with a Buy rating and $10 price target, Citizens came in with a Market Outperform rating and $10 target, and Cantor Fitzgerald launched coverage with an Overweight rating.

The stock itself was trading down 4.45% at $4.94 on Monday, according to market data.