The Food and Drug Administration rejected a first-of-its-kind cancer drug that was invented in China, a setback for a medicine that had become a symbol of China’s ascendance as a powerhouse in drug development.
Summit Therapeutics, the Florida company that has been seeking to bring the drug to the American market, disclosed the agency’s decision in a news release on Sunday. Summit bought the U.S. rights to the drug from Akeso Biopharma, a Chinese drugmaker that invented the drug in its laboratories and sells it in China.
Summit had been seeking approval only for certain patients with advanced lung cancer. But the drug had raised high hopes because it is being tested in many more cancers, including tumors of the colon, bladder and breast.
Summit said on Sunday that the F.D.A. told the company it had rejected the drug because it had not shown a statistically significant benefit in prolonging patients’ lives in the global clinical trial that was the basis of Summit’s application.
Summit had been seeking F.D.A. approval based on the results of a study the company conducted in the United States, Canada, Europe and Asia that enrolled patients who had already tried a targeted treatment. The trial compared patients who received ivonescimab and chemotherapy with those whose only treatment was chemotherapy. In that study, the drug was successful in delaying the cancer’s progression.
Summit has argued that the failure to extend patients’ lives simply reflected slow enrollment in the study. Hoping to bolster its case, the company had sent the F.D.A. analyses that were not specified in the original research plan of patients’ longer-time outcomes, but those were not enough to persuade regulators.
The F.D.A. did not return a request for comment on its decision, as is typical with rejections.
The drug, given as an intravenous infusion, is novel because it combines two attacks on a tumor. It unleashes the immune system with one strategy and deprives the tumor of a blood supply with another. Large drugmakers like Merck and Pfizer are developing medicines that take the same approach.
Ivonescimab’s boosters had hoped that the drug would eventually displace Keytruda, the world’s best-selling cancer medicine that is used to treat a broad range of cancer types. But cancer researchers around the world have said that the clinical trial results so far have not justified such widespread use.
The rejection comes as a flurry of promising experimental drugs are emerging from Chinese laboratories and fueling fierce debate about whether the United States is ceding its longstanding dominance in biotechnology to China.
People who support the activity point out that American patients can benefit from Chinese innovation. But Chinese drugmakers face fewer regulatory hurdles and can move more quickly than their American counterparts, a dynamic that some American lawmakers, investors and executives say puts U.S. companies at a deep disadvantage.
And as more medicines show promise in clinical trials in China, researchers around the world have voiced concern that drugs may not work as well in American patients as they do in Chinese patients, for reasons that are not fully understood. American regulators have insisted on seeing data in Western populations before approving cancer drugs from China.
For decades, the world’s top-selling drugs were generally invented in laboratories in the United States or Europe. China was seen as a sleepy manufacturer of generic medicines and drug ingredients. But that has been changing as China’s biotechnology industry has surged in recent years, churning out patents, papers and cutting-edge experimental drugs.
The blood cancer medications Brukinsa and Carvykti were invented in China and now generate over $1 billion in annual revenue in the United States.
To bring drugs invented in China to American patients, Chinese companies sometimes sell the U.S. rights to American drugmakers, as Akeso and Summit did with ivonescimab. These types of deals would continue to be permitted under new proposed regulations from the Trump administration prohibiting U.S. companies and investors from taking investment stakes in Chinese biotechnology.
Around the globe, ivonescimab is being tested in 17 continuing, completed or planned late-stage studies, according to Summit.
Most of interest to cancer researchers is a clinical trial of ivonescimab that is expected to report results before the end of this year. That study enrolled patients in the United States, China and other countries who have not yet tried a treatment for their advanced lung cancer. It will assess whether ivonescimab is better than Keytruda at prolonging lives and extending the time until cancer progresses.
If that study succeeds, Summit is expected to seek F.D.A. approval for the drug to be used in that setting.
In the news release on Sunday, Bob Duggan, a co-chief executive officer of Summit, said that even with the F.D.A.’s decision, “nothing changes with respect to our ever-growing belief in the opportunity for ivonescimab and our determination to advance ivonescimab’s development.”