US regulators have rejected ivonescimab, a lung-cancer drug invented in China, dealing a setback to Summit Therapeutics’ attempt to introduce the treatment to the American market.
Summit, a Florida-based company, said the Food and Drug Administration had refused its application after concluding that a global clinical trial had not shown a statistically significant benefit in extending patients’ lives.
The company had sought approval for certain patients with advanced lung cancer who had already received a targeted treatment. The study compared ivonescimab combined with chemotherapy against chemotherapy alone among patients in the US, Canada, Europe and Asia.
Although the treatment delayed the progression of the disease, it did not meet the trial’s measure for prolonging survival. Summit argued that slow enrolment had affected the survival results and submitted further analyses covering patients’ longer-term outcomes, but these did not persuade regulators.
The FDA did not comment on the decision, as is customary when it rejects a medicine application.
Ivonescimab’s next test
Ivonescimab is administered by intravenous infusion and is designed to attack tumours in two ways. It stimulates the immune system while also restricting the blood supply that tumours need to grow.
The drug has attracted interest beyond lung cancer and is being tested in tumours including those of the colon, bladder and breast. Summit said it is involved in 17 continuing, completed or planned late-stage studies around the world.
The most closely watched trial is expected to produce results before the end of this year. It involves patients in the US, China and other countries who have not previously received treatment for advanced lung cancer, and will compare ivonescimab with Keytruda on survival and the time before the cancer worsens.
A successful result could lead Summit to seek approval for use in that earlier treatment setting. Supporters of ivonescimab had hoped it might eventually challenge Keytruda, the world’s best-selling cancer medicine, but researchers have said results so far do not support such broad use.
Chinese drug development
The rejection comes amid growing debate over China’s expanding role in biotechnology. Chinese laboratories are producing increasing numbers of patents, scientific papers and experimental medicines, after the country was long regarded mainly as a manufacturer of generic drugs and pharmaceutical ingredients.
Akeso Biopharma, the Chinese company that developed ivonescimab, sold the US rights to Summit. Similar agreements allow American patients to gain access to medicines created in China, although researchers have raised questions about whether treatments tested primarily in Chinese patients will perform in the same way among Western populations.
US regulators have insisted on data from Western populations before approving cancer medicines developed in China. Summit’s co-chief executive, Bob Duggan, said the FDA decision had not altered the company’s confidence in ivonescimab or its determination to continue developing it.
