Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 3INTERVENTIONAL

A Study to Confirm the Effectiveness and Safety of AK0529 in Treating RSV Infections in Hospitalized Infants

A Randomized, Double-blind, Placebo-controlled, Phase III Confirmatory Study to Evaluate the Efficacy, Safety, Tolerability, and Antiviral Activity of Repeated Oral Administration of AK0529 in Hospitalized Infants with Respiratory Syncytial Virus Infection

A Study to Confirm the Effectiveness and Safety of AK0529 in Treating RSV Infections in Hospitalized Infants (NCT06775405) is a Phase 3 interventional studying Respiratory Synctial Virus Infections, sponsored by Shanghai Ark Biopharmaceutical Co., Ltd.. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

Respiratory syncytial virus (RSV) is the most common respiratory infectious pathogen recognized worldwide that poses serious health risks to infants, and an important cause of hospitalization for severe respiratory infections in infants. Serious respiratory problems such as pneumonia caused by RSV are one of the leading causes of death from respiratory diseases in infants. AK0529 targets the Pre-F (fusion) protein on the surface of the viral envelope. Specifically, it prevents the virus from invading uninfected cells and inhibits the fusion between host cells by inhibiting the fusion of the F (fusion) proteins on the surface of the RSV envelope, thus providing the effects of anti-RSV infection. This is a randomized, double-blind, placebo-controlled, multicenter, phase III clinical study to evaluate the efficacy and safety of AK0529 in hospitalized infants aged 1 to 24 months with RSV infection. Considering the benefits of AK0529 in the population with RSV infection, hospitalized infants with moderate to severe RSV infection were selected as the target population for this study.

What Stage of Research Is This?

Phase 3 trials confirm efficacy and safety in large patient groups (often 300–3,000+) and form the evidence base for an FDA approval submission. For Respiratory Synctial Virus Infections, Phase 3 studies typically randomize participants between the investigational treatment and either a placebo or current standard of care. A successful Phase 3 result is the threshold most treatments need to clear before regulatory approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 180 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Respiratory Synctial Virus Infections subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Main Who May Qualify: 1. Male or female subjects of any ethnicity with an age adjusted for any prematurity of ≥1 month and ≤24 months. 2. Diagnosis of RSV infection by any virological means, including a rapid diagnostic point-of-care testing, within 36 hours preceding initial dosing. 3. The onset of RSV infection symptoms should be ≤ 5 days prior to initial dosing. 4. Subject must weigh ≥ 2.5 kg and ≤ 20 kg at screening and be within the normal range for the subject's age, based on local child growth standards. 5. Subject must have a Wang bronchiolitis clinical score ≥ 5. Main Who Should NOT Join This Trial: 1. The subject has taken any restricted medications within 3 days prior to the date of screening or requires any restricted medications during treatment phase (including interferons, ribavirin, or proprietary Chinese medicines with antiviral effects) and has taken any inhaled or systemic glucocorticoids within 24 hours. 2. Subject is known to have co-infection with influenza virus, Mycoplasma, or other respiratory tract pathogens that require targeted clinical treatment . 3. Subject is known to have bacterial pneumonia. 4. Subject with clinical evidence of hepatic decompensation (e.g., liver disease with coagulation abnormalities or encephalopathy). 5. Subject with inborn symptoms of metabolic abnormalities (e.g., mitochondrial diseases, carbohydrate metabolism abnormalities, glycogen accumulation diseases). 6. Subject with chronic or persistent feeding difficulties. 7. The parent or guardian of the subject is an employee of the study investigator or the study facility (such person will be directly involved in the study or any other study administered by the study facility investigator), or a family member of the study investigator or his/her staff. 8. Subject who have participated in clinical trials of other drugs or devices in the 30 days prior to screening. ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Main Inclusion criteria: 1. Male or female subjects of any ethnicity with an age adjusted for any prematurity of ≥1 month and ≤24 months. 2. Diagnosis of RSV infection by any virological means, including a rapid diagnostic point-of-care testing, within 36 hours preceding initial dosing. 3. The onset of RSV infection symptoms should be ≤ 5 days prior to initial dosing. 4. Subject must weigh ≥ 2.5 kg and ≤ 20 kg at screening and be within the normal range for the subject's age, based on local child growth standards. 5. Subject must have a Wang bronchiolitis clinical score ≥ 5. Main Exclusion criteria: 1. The subject has taken any restricted medications within 3 days prior to the date of screening or requires any restricted medications during treatment phase (including interferons, ribavirin, or proprietary Chinese medicines with antiviral effects) and has taken any inhaled or systemic glucocorticoids within 24 hours. 2. Subject is known to have co-infection with influenza virus, Mycoplasma, or other respiratory tract pathogens that require targeted clinical treatment . 3. Subject is known to have bacterial pneumonia. 4. Subject with clinical evidence of hepatic decompensation (e.g., liver disease with coagulation abnormalities or encephalopathy). 5. Subject with inborn symptoms of metabolic abnormalities (e.g., mitochondrial diseases, carbohydrate metabolism abnormalities, glycogen accumulation diseases). 6. Subject with chronic or persistent feeding difficulties. 7. The parent or guardian of the subject is an employee of the study investigator or the study facility (such person will be directly involved in the study or any other study administered by the study facility investigator), or a family member of the study investigator or his/her staff. 8. Subject who have participated in clinical trials of other drugs or devices in the 30 days prior to screening. 9. Subject with any other reason that the investigator deems unsuitable for participation in the study.

Treatments Being Tested

DRUG

AK0529

Active Substance: AK0529, Pharmaceutical Form: Enteric pellets, Route of Administration: Oral

DRUG

Placebo

Active Substance: Placebo, Pharmaceutical Form: Enteric pellets, Route of Administration: Oral

Locations (18)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Beijing Children's Hospital, Capital Medical University

Beijing, China

Beijing Children's Hospital, Capital Medical University

Beijing, China

First Hospital of Jilin University

Changchun, China

Hunan Provincial People's Hospital

Changsha, China

West China Second University Hospital, Sichuan University

Chengdu, China

Children's Hospital, Zhejiang University School of Medicine

Hangzhou, China

Sanya Central Hospital, Hainan Third People's Hospital

Sanya, China

Shanghai Children's Hospital, Shanghai Jiao Tong University

Shanghai, China

Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine

Shanghai, China

Shengjing Hospital of China Medical University

Shenyang, China

Tianjin Children's Hospital（Longyan）

Tianjin, China

Tianjin Children's Hospital（Machang）

Tianjin, China

Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University

Wenzhou, China

Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology

Wuhan, China

Wuxi Children's Hospital

Wuxi, China

First Affiliated Hospital of Xiamen University

Xiamen, China

Women and Children's Hospital, and the School of Medicine, Xiamen University

Xiamen, China

Zhongshan Women and Children's Hospital-Zhongshan Boai Hospital

Zhongshan, China

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT06775405), the sponsor (Shanghai Ark Biopharmaceutical Co., Ltd.), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT06775405 clinical trial studying?

Who can participate in NCT06775405?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT06775405?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT06775405. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT06775405. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.