A clinical study led by the Shanghai-based Children's Hospital of Fudan University, in collaboration with 28 other medical institutions across China, has proved that hormone therapy does not reduce the risk of life-threatening cardiovascular complication in children with Kawasaki disease, addressing a decades-long question in the global medical community. 

According to medical experts, the study, the largest of its kind worldwide, could provide crucial guidance for avoiding hormone overuse in treating the systemic vasculitis which predominantly affects children under 5, as well as providing significant insights into improving treatment efficacy, reducing severe cases and lowering mortality rates.

Researchers have said the study will provide a valuable reference for developing targeted therapies against vascular wall inflammation and preventing the progression of coronary artery lesions in Kawasaki disease.

A paper about the clinical research, which took five years to complete, was published on the website of The New England Journal of Medicine on Thursday. 

Kawasaki disease, a condition seen globally but with a higher incidence rate in East Asia, where cases are on the rise, still throws up many unresolved questions for medical practitioners. In China, one in every 1,000 children aged under 4 is diagnosed with the disease annually. 

The most challenging feature of the disease is the complication of coronary artery lesions. Despite the existing standard treatment internationally, 10 to 20 percent of affected children still develop coronary artery lesions, while giant coronary artery aneurysms occur in 0.5 to 1 percent of treated patients, impacting long-term outcomes and posing life-threatening risks.

Over the past two decades, conflicting international studies have debated the efficacy of hormone therapy in reducing inflammation and coronary artery complication in Kawasaki disease, largely due to varying study populations, small sample sizes and differing hormone protocols. Such discrepancies have led to confusion in clinical practice.

Initiated in 2021, this multicenter, randomized trial led by the hospital in Shanghai enrolled more than 3,200 participants, with 3,058 completing follow-up for the primary endpoint. The study found no statistically significant difference in the rates of coronary artery lesions between the groups with and without the hormone therapy at two weeks, one month and three months after the disease onset.

Their research also showed that, for patients who do not respond to the standard treatment, the use of hormones increased the risk of developing the complication.

Experts around the world have said the research will provide a new perspective for developing targeted medicines for the disease.

"Future research must move beyond conventional markers to identify the specific biologic factors driving tissue-level inflammation and to enable the development of targeted therapies for the children at highest risk for life-threatening cardiovascular complications," said Jane W. Newburger, a renowned cardiologist from the United States.

Wang Yi, president of the Children's Hospital of Fudan University, said that the research results will inspire new studies. She added that doctors will continue their work on targeting the disease and on uncovering new mechanisms to promote the clinical development and use of new targeted drugs. 

"Our hospital treated over 7,000 child patients from overseas last year, and most of them suffered from critical genetic diseases that required the healthcare team to race against time," said Wang.

"The hospital's effort in leading on research like this will help clarify the logic of such diseases, guide the development of relevant disciplines, and contribute to establishing Shanghai as a global medical hub," she said.