Lung cancer encompasses several diseases. Some tumors have a specific alteration, called ROS1, which promotes their development. The U.S. FDA has just approved a new drug, Jideytro, for adults whose cancer has spread or cannot be removed by surgery.
ROS1 corresponds to a protein present in certain cells. It normally serves to transmit signals. In the affected tumors, it can remain abnormally active and drive cells to multiply. Jideytro, whose scientific name is zidesamtinib, blocks this protein to slow or stop this multiplication.
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This decision concerns only certain lung cancers called "non-small cell". They must have the ROS1 alteration and have already received at least one treatment targeting this protein. These drugs, taken as tablets, act on a specific characteristic of the tumor rather than on all rapidly dividing cells.
The interest of Jideytro lies particularly in its activity against certain resistances. Over time, cancer cells can change and escape the initial treatment. The molecule was designed to remain active against several of these modifications.
The approval is based on ARROS-1, an international phase 1/2 clinical trial. This study evaluated the drug in patients whose cancer had already been treated. The analysis retained by the FDA involved 117 people: 59 had received a treatment targeting ROS1 and 58 had received at least two.
After treatment, tumor size decreased in 44% of participants. Among responding patients, 82% maintained this improvement after six months. This rate still reached 69% after one year. These figures indicate real drug activity, but they do not yet allow us to say that it cures the disease.
The trial did not directly compare Jideytro with another treatment. It mainly measured the proportion of patients whose tumors shrank, as well as the duration of this response. More follow-up is therefore needed to know precisely its effect on survival and its place among available treatments.
The FDA approved zidesamtinib on July 22, 2026, two months ahead of schedule. The review was accelerated thanks to a mechanism allowing certain data to be studied during their submission.
The treatment is taken orally, at a dose of 100 mg once daily.