Is Zai Lab (ZLAB) Cheap After Its ESMO 2026 Lung Cancer Data Update?

ESMO data disclosure puts Zai Lab's early lung cancer program in focus

Zai Lab (ZLAB) has put fresh attention on its pipeline after confirming that global Phase 1b/1c data for zocilurtatug pelitecan in extensive-stage small cell lung cancer will appear at the ESMO Congress 2026.

The ESMO update lands after a mixed period for Zai Lab, with the share price down 7.24% over the past 30 days, yet up 27.52% on a 90 day basis and 40.39% year to date, while the 1 year total shareholder return is still down 27.91%, signaling recent momentum building off a weaker long term base.

Surf 19 high quality undiscovered gems that, like Zai Lab, are trying to turn high impact clinical catalysts into the next wave of oncology-driven momentum.

Recent gains in Zai Lab look like a sharp change in tone after years of weak shareholder returns. Is this move finally tracking business progress, or just sentiment swinging around a single catalyst as investors reassess valuation?

Most Popular Narrative: 27% Undervalued

On the most followed narrative, Zai Lab screens as undervalued, with a fair value of $33.30 against a last close of $24.33. This puts the current rally in the context of a larger rerating argument rather than just a short term reaction to ESMO headlines.

Multiple high-potential product launches and label expansions over the next 12-18 months (including VYVGART, bemarituzumab, KarXT, TIVDAK, Tumor Treating Fields), combined with a deep pipeline in oncology and immunology, are expected to significantly increase Zai Lab's addressable market and diversify revenue streams, supporting both top-line growth and future earnings.

See why 12 investors see Zai Lab as 27% undervalued .

Result: Fair Value of $33.30 (UNDERVALUED)

Still, the bullish Zai Lab narrative can crack if China pricing reforms squeeze margins further, or if reliance on licensed drugs keeps royalty costs stubbornly high.

Find out about the key risks to this Zai Lab narrative .

Another View: Zai Lab on Sales-Based Valuation

There is a catch. While the SWS model flags Zai Lab as undervalued on future cash flows, the P/S picture looks harsher. At 6.1x sales, the stock sits only slightly above peers at 6.0x, yet almost double its own estimated fair ratio of 3.4x. That gap points to meaningful valuation risk if sentiment cools.

To see how those sales multiples line up with the rest of the sector and where the fair ratio suggests the market could drift toward, See what the numbers say about this price — find out in our valuation breakdown.