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Study on AON-D21 for Patients with Severe Community-Acquired Pneumonia in Intensive Care

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the treatment of Severe Community-Acquired Pneumonia, a serious lung infection that people can catch outside of a hospital setting. The treatment being tested is called AON-D21, which is a special type of medication known as an aptamer. Aptamers are molecules that can bind to specific targets in the body, similar to how antibodies work. In this study, AON-D21 is given as a solution through an intravenous infusion, meaning it is administered directly into the bloodstream.

The purpose of the study is to assess the safety and tolerability of AON-D21 in patients with severe pneumonia who are admitted to an intensive care unit. Participants in the study will receive either the AON-D21 treatment or a placebo, which is a solution that does not contain the active medication. The study will follow participants over a period of time to monitor their response to the treatment and any side effects they may experience.

Throughout the study, researchers will observe how long it takes for patients to no longer need respiratory support, which includes various forms of oxygen therapy and mechanical ventilation. They will also track the number of days patients are free from needing organ support and any changes in their condition over time. The study aims to provide valuable information on the potential benefits and risks of using AON-D21 as an additional treatment for severe pneumonia.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the patient is required to have a confirmed or suspected case of severe community-acquired pneumonia. This condition may be of bacterial or viral origin.

    The patient must be admitted to an intensive care unit or a similar facility that provides specialized medical and nursing care.

  2. Step 2

    Initial assessment

    Before receiving the first dose, the patient undergoes an assessment to confirm the need for respiratory support. This includes high-flow oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation.

    A blood test is conducted to measure C-reactive protein levels, which must be 50 mg/L or higher.

  3. Step 3

    Treatment initiation

    Treatment with the study drug, AON-D21, or a placebo begins within 48 hours of starting respiratory support.

    The medication is administered intravenously as a solution for infusion.

  4. Step 4

    Monitoring and follow-up

    The patient is monitored for any adverse events related to the treatment until Day 28.

    The study evaluates the time taken for the patient to no longer require respiratory or organ support within 28 days.

  5. Step 5

    End of study participation

    The study concludes with an assessment of the patient's condition, including any changes in respiratory support needs and overall health status.

    The primary focus is on the safety and tolerability of AON-D21 in treating severe community-acquired pneumonia.

Who can join the trial?

11 criteria

  • The patient must have **community-acquired pneumonia**. This is a type of lung infection that you get outside of a hospital setting. It can be caused by bacteria or viruses.
  • Female patients who can have children must agree to use two methods of birth control until Day 60 of the study.
  • Male patients with female partners who can have children must agree to use a barrier method of birth control until Day 60 and not donate sperm during the study and for 3 months after the last treatment.
  • The patient must be admitted to an **Intensive Care Unit (ICU)** or a similar unit. This is a special hospital area where patients receive intensive medical care and monitoring.
  • The patient must need **respiratory support**. This means they need help with breathing, such as high-flow oxygen, non-invasive or invasive mechanical ventilation, or a machine called **extracorporeal membrane oxygenation** (ECMO).
  • The patient must have a **C-reactive protein** level of at least 50 mg/L. This is a blood test that shows inflammation in the body.
  • The patient must have a **PaO2/FiO2 ratio** of 300 mmHg or less. This is a measure of how well oxygen is being transferred from the lungs to the blood.
  • The treatment must start no more than 48 hours after the patient begins receiving respiratory support.
  • The patient or their legal representative must provide written consent to participate in the study. In emergencies, a doctor not involved in the study can give permission, but the patient or their representative should be informed as soon as possible.
  • The patient must be between 18 and 85 years old.
  • The patient must have a **body mass index (BMI)** between 17.5 and 40 kg/m². BMI is a measure of body fat based on height and weight.

Who cannot join the trial?

5 criteria

  • Patients who have a different type of pneumonia that is not classified as Severe Community-Acquired Pneumonia cannot participate. This means the pneumonia must be severe and acquired outside of a hospital setting.
  • Patients who are not admitted to an Intensive Care Unit or a similar unit are excluded. An Intensive Care Unit is a special department in a hospital that provides intensive treatment and monitoring.
  • Patients who are outside the specified age range for the study cannot participate. The study is only for certain age groups.
  • Patients who do not meet the gender requirements of the study are excluded. The study includes both male and female participants.
  • Patients who are considered part of a vulnerable population may be excluded. Vulnerable populations include groups that may have a higher risk of harm or exploitation.
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Investigated drugs

AON-D21 is an investigational medication being studied for its potential to help patients with severe community-acquired pneumonia. This trial aims to evaluate how safe and tolerable this medication is for patients who are admitted to the Intensive Care Unit or a similar unit. The study is designed to see if AON-D21 can improve the condition of patients suffering from this serious type of pneumonia.

What is already known about the treatment

AON-D21 – AON-D21 is administered intravenously, typically in a hospital setting, particularly for patients in intensive care units. It is currently being studied in clinical trials to evaluate its safety and effectiveness for treating severe community-acquired pneumonia. The medication is designed to help manage severe infections by modulating the immune response, potentially reducing inflammation and aiding recovery. AON-D21 falls under the category of immunomodulatory agents, which work by altering the immune system's activity to improve health outcomes.

Investigated diseases

Severe Community-Acquired Pneumonia – This is a serious lung infection acquired outside of a hospital setting. It is characterized by inflammation of the air sacs in one or both lungs, which may fill with fluid or pus, causing symptoms such as cough, fever, chills, and difficulty breathing. The disease progresses rapidly and can lead to severe respiratory distress, requiring hospitalization and intensive care. Patients may experience a significant decline in lung function, necessitating respiratory support such as oxygen therapy or mechanical ventilation. The condition can also affect other organs, leading to complications like sepsis or organ failure. Recovery can be prolonged, with patients needing extended periods of medical support and monitoring.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-505985-28-01Protocol codeS-D21-C300Estimated enrolment160 patientsSponsorAptarion Biotech AG

sourced from the EU Clinical Trials Register and site verification

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