New data dims Summit-Akeso's lung cancer drug in China

China approved ivonescimab for a new use on Aug. 12, the drug's third approval there. Days later, updated trial data told a less rosy story. With about 7 more months of patient follow-up, the drug's benefit shrank. It now cuts the risk of disease progression or death by 28%, down from an earlier reported 40%.

That kind of fade isn't unusual, and it isn't necessarily a red flag on its own. Early trial results often look their best right after the data cutoff, then settle as more patients are tracked longer. What makes this one worth watching is the timing. The softer numbers landed the same week as a fresh approval. That's right when Akeso and Summit most wanted a clean story. Summit's U.S. investors are counting on this drug reaching American patients. They now have a real reason to ask how much of the original excitement holds up.

Keep reading — what to watch

Will the benefit keep shrinking as more follow-up data comes in, or is this settling to a new, still-solid baseline? Cancer drugs routinely look different a year or two after their first headline results. The next data update will show which one this is.