ArkBio Announces Completion of Patient Enrollment and Dosing in AIRFLO, a Phase III Registration Trial of Ziresovir for Treatment of Respiratory Syncytial Virus Infection
Release date:2022-01-25

On January 25, 2022, Shanghai Ark Biopharmaceutical Co., Ltd. (ArkBio) announced the completion of patient enrollment and dosing of ziresovir (AK0529) for the treatment of respiratory syncytial virus (RSV) infection in a Phase III registration clinical trial. The Phase III trial, named AIRFLO, is designed to evaluate clinical efficacy, safety, tolerance, pharmacokinetics, and antiviral effect of ziresovir in hospitalized infants and children with RSV infection. This is the first time ever that a phase III clinical trial of an RSV-specific therapeutic has been completed. Topline results are expected to be available in the first half of 2022.


“RSV is the number one cause of hospitalization and death in children under five years of age worldwide. Over 96% of children are infected with RSV before they reach two years of age. Currently there are no effective treatments available, which presents a huge unmet medical need.” Commented by Yan Wu, M.D., Chief Medical Officer of ArkBio, “The successful completion of the AIRFLO study marks an important milestone towards marketing approval for ziresovir.”


The AIRFLO study is a randomized, double-blind, placebo-controlled, multicenter clinical study for the evaluation of efficacy, safety, and antiviral effect of ziresovir in the treatment of RSV infection in hospitalized infants and children. A total of 311 patients were randomized and dosed with ziresovir or placebo at a 2:1 ratio twice daily for 5 consecutive days. The primary endpoint is the change of bronchiolitis sign and symptom score from baseline.


“With the advent of Chinese New Year, we are excited to achieve this important milestone. Pediatric clinical trial of innovative drugs often presents with many obstacles and challenges. The successful completion of patient enrollment and dosing in the AIRFLO study could not have been achieved without the dedication and diligence of our ArkBio team.” Dr. Jim Wu, chairman and CEO of ArkBio, emphasized, “More importantly, it attributes to the great efforts and professionalism of the PIs, medical and administrative staff from the top thirty children’s hospitals that participated in this study. We would also like to express our sincere gratitude to the patients and their parents for trust and cooperation. ArkBio will continue to focus on patient’s needs and work closely with medical community to develop innovative pediatric drugs to safeguard the healthy growth of children.”



About respiratory syncytial virus


Respiratory syncytial virus (RSV) is a highly prevalent airborne RNA virus. It enters the trachea and lungs through oral and nasal inhalation, invades epithelial cells, causes cell death, and can lead to excessive airway mucus, lumen blockage, and dyspnea. The common symptoms of RSV infection are runny nose, fever, cough, and wheezing. Under serious conditions, it causes respiratory distress and even complete airway blockage, leading to respiratory failure and death. The most susceptible population of RSV are children, the elderly and adults with impaired immune function. At present, there are no effective treatments specifically targeting RSV. There exist huge unmet medical needs for the treatment of RSV infection.


RSV is particularly harmful to children. According to the WHO data, RSV is the number one cause of hospitalization and death in children under five years of age worldwide. According to statistics of 2020, there were ~35 million children under 5 years of age who are infected with RSV in the world, with more than 3 million in China, and up to 200,000 deaths globally. Even for children with mild symptoms, if not treated timely, it may develop into chronic respiratory diseases, such as wheeze and asthma, which will affect a child’s long-term growth and development.



About ziresovir


Ziresovir (AK0529) 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 and viral infection. It can also suppress virus transmission through cell fusion, i.e., formation of "syncytia", a characteristic event of RSV infection of host cells.


Ziresovir is the first anti-RSV drug globally to successfully complete a phase II proof-of-concept study in hospitalized infant patients and the first to enter a phase III registration clinical study. It is also one of the first innovative pediatric drugs that is tested in clinical trials in China. The drug has received national support and recognition in China such as a breakthrough designation. It is the first non-oncology drug that received breakthrough designation from China regulatory authority NMPA.



About ArkBio


ArkBio is a global biopharmaceutical company focusing on discovery and development of innovative drugs for unmet medical needs, especially in pediatric and respiratory disease areas. Since its inception in 2014, the company has established core technology platforms and has created innovative drugs with global patent protection. Through in-house R&D efforts and external collaborations, the company has developed a promising and highly differentiated product pipeline. The core product, ziresovir, is the world's leading anti-RSV therapeutic drug that has received a breakthrough designation from China’s regulatory authority NMPA. Another near-commercial asset is an ADHD (attention deficit hyperactivity disorder) drug AZSTARYS recently approved by FDA. ArkBio owns the right for its development and marketing in Greater China. The pipeline programs also include a battery of clinical and pre-clinical stage drug candidates with first- or best-in-class potential for global development.


ArkBio has a track record of successful collaboration and partnership with multinational pharma companies such as Roche and Genentech, world leading academic institutions such as The Scripps Research Institute in the US, the Institute of Microbiology of Chinese Academy of Sciences, domestic and global biotech companies, as well as multinational investment institutions.


ArkBio aims to become a leading global biopharmaceutical company with integrated technology platforms for drug discovery and development, manufacturing, and commercialization in pediatric and respiratory therapeutic areas.


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