ArkBio Announces Publication of Phase 3 Clinical Trial Results of Ziresovir for the Treatment of RSV Infection in The New England Journal of Medicine

SHANGHAI, Sept. 26, 2024 /PRNewswire/ -- Shanghai Ark Biopharmaceutical Co., Ltd. ("ArkBio"), a clinical stage biopharmaceutical company focused on the development of therapeutics in respiratory, infectious and pediatric diseases, announced that the results of the phase 3 clinical trial of ziresovir, an oral drug for treatment of respiratory syncytial virus (RSV) infection in infants and young children, have been published as an original article entitled "Ziresovir in Hospitalized Infants with Respiratory Syncytial Virus"in The New England Journal of Medicine (NEJM). This marks the first time that NEJM has published phase 3 clinical trial results of a direct-acting antiviral drug treating RSV infection. This landmark study, led by Professors Xin Ni and Shunying Zhao from Beijing Childrens'Hospital, Capital Medical University, represents a significant milestone in the field of RSV antiviral development, where worldwide, there are no effective treatments for RSV infections available. In addition, the NEJM publication is accompanied by an editorial written by Professor Edward Walsh entitled "Creeping Towards Effective Antiviral Agents for RSV Infection", which regards the results of the phase 3 ziresovir clinical study to be encouraging.

RSV is the leading cause of hospitalized infants with respiratory infections and can cause serious respiratory complications such as bronchiolitis and pneumonia. For high-risk premature infants and those with congenital conditions, RSV infection can be serious and potentially life-threatening. Moreover, infants who suffer from an RSV infection are at a significantly higher risk of recurrent wheezing and asthma in later childhood. Among adults, severely immunocompromised patients and the elderly are at the highest risk for severe RSV infection, which can lead to hospitalization and death.

A total of 30 leading children's hospitals or pediatric departments of general hospitals across China participated in this randomized, double-blind, placebo-controlled phase 3 clinical trial, enrolling 311 infants or young children aged 1 to 24 months who were hospitalized due to RSV infection. These participants were randomly assigned in a 2:1 ratio to ziresovir or placebo twice a day for a 5-day treatment period. The primary outcome measure was the change in the Wang bronchiolitis clinical score from baseline after 48 hours of treatment. The key secondary endpoint was the change in RSV viral load from baseline after 96 hours of treatment.

Study Results:

• Significant Efficacy: In the ziresovir treatment group, the average reduction in bronchiolitis clinical score was 3.4 points after 48 hours of the first dose, compared to a 2.7-point reduction in the placebo group which reached statistical significance (P=0.002).
• Significant Reduction in Viral Load: The ziresovir treatment group showed an average decrease in RSV viral load of 2.5 log10 copies/mL 96 hours after the first dose, while the placebo group showed a decrease of 1.9 log10 copies/mL, representing a 77% greater reduction in the treatment group which was statistically significant (P=0.006).
• Excellent Safety Profile: The incidence of drug-related adverse events was 16% in the ziresovir treatment group and 13% in the placebo group. No serious drug-related adverse events were observed and there were no deaths.

These results indicate that as a novel direct-acting oral antiviral drug, ziresovir is an effective treatment for infants and young children hospitalized with RSV infection and has a favorable safety profile.

Professor Xin Ni, a leading principal investigator of Beijing Children's Hospital, Capital Medical University, stated: "RSV infection has long been a serious medical challenge in pediatric healthcare. This virus not only poses a threat to children's health, but also places a heavy burden on our healthcare system. For a long time, we have been searching for a safe and effective treatment. Today, our team has made significant progress in the management of this illness. We are grateful to The New England Journal of Medicine for recognition of our clinical study. This is the first successful phase 3 clinical trial of a direct-acting antiviral drug for the treatment of hospitalized infants with RSV infection. This research will bring hope to millions of families with their children being infected by RSV globally. We look forward to the approval of ziresovir for treatment of RSV infection in China and around the world for children to grow up free from the threat of RSV infection".

Dr. Jim Wu, CEO of ArkBio, added："The phase 3 clinical trial results of ziresovir in the treatment of hospitalized infants and young children are encouraging, as the study confirms that ziresovir is a well-tolerated and efficacious antiviral drug for the treatment of RSV infection. As the sponsor of the study, we are deeply grateful to all the patients and parents, the investigators and their teams, and all our partners who actively participated in the study. Under the guidance of the regulatory agencies, we will continue to develop the drug in collaboration with the medical community. We are committed to the research and development of innovative medicines to safeguard the wellbeing and healthy growth of children".

About ziresovir

Ziresovir is a novel small-molecule RSV fusion (F) protein inhibitor. It binds to the F protein of the virus and prevents viral entry into human cells. Ziresovir can also suppress RSV viral transmission by blocking cell-to-cell fusion through the formation of "syncytia", a characteristic event of RSV infection of host cells.
Ziresovir is the first oral anti-RSV drug that has completed a phase 3 pivotal clinical study with positive results. Ziresovir is the first non-oncology investigational product that received Breakthrough Therapy designation by the National Medical Products Administration (NMPA) of China.

About ArkBio

ArkBio is a global biotech company focusing on discovery and development of innovative drugs for unmet medical needs, especially in the therapeutic areas of respiratory, infectious and pediatric diseases. Since its inception in 2014, the company has established core technology platforms and built an innovative and highly differentiated R&D pipeline through in-house R&D efforts and external collaborations. This strong R&D pipeline program includes innovative clinical and pre-clinical stage drug candidates with first- or best-in-class potential for global clinical development. As one of the core assets, ziresovir is the first direct-acting RSV antiviral drug that has been developed by ArkBio.

ArkBio has established strategic partnerships with several global pharmaceutical companies and academic institutes, including Roche, Genentech, the Scripps Research Institute, the Institute of Microbiology of Chinese Academy of Sciences, domestic and international biotechnology companies, as well as venture investment institutions. 

For more information about the company, please visit our website: www.arkbiosciences.com

Investor Inquiries: IR@arkbiosciences.com

source: Arkbio