Researchers are conducting an exciting new clinical trial with the hope of finding a way to reduce the severity of organ injury and improve recovery in people with acute respiratory distress syndrome (ARDS). Phase 2 of the study is in progress and participants are being recruited at University of California – San Francisco, Ohio State University, University of Pittsburgh, Stanford, and Massachusetts General Hospital.
What Is Acute Respiratory Distress Syndrome?
People who are severely ill and hospitalized are prone to developing life-threatening reactions and infections in the lungs. This condition is known as ARDS. It is characterized by reduced gas exchange due to inflammation and hypoxemia. ARDS has a high mortality rate of up to 40 percent. Survivors are often left with lung damage that is permanent.
What are mesenchymal stem cells?
Some human tissues, such as the bone marrow, adipose tissue, the placenta, and cord blood contain precursor cells called mesenchymal stem cells. MSCs have the impressive ability to differentiate into different types of body tissues including fat, muscle, cartilage, and bone. In addition, MSCs improve recovery and reduce the severity of injury to organs.
Stem Cell Trial for Adult Respiratory Distress Syndrome
Phase 1 of the single group assessment trial enrolled 9 patients and was completed without any adverse events. In phase 2 of the multi-center randomized trial, 40 patients have been enrolled and a further 20 enrollments are planned. For every two patients who receive mesenchymal stem cells, one patient will receive a placebo for a 2:1 ratio. The stem cell treatment for ARDS can be given within 120 hours of symptom onset. However, to be included in the study, participants must have within 24 hours of randomization the following three criteria:
- Infiltrates in bilateral lungs with evidence of pulmonary edema on chest X-ray
- No evidence clinically of left atrial hypertension
- Need for tracheal tube or endotracheal tube positive pressure ventilation with a PEEP of at least 8 and PaO2/FiO2 ratio less than 200
Children are excluded from the study (minimum age 18 years), as are pregnant or breastfeeding females, prisoners, people with liver failure, malignancies, major trauma, pulmonary hypertension, and pulmonary embolism, among others. Again, if more than 96 hours have passed since the inclusion criteria were met, the patient is not eligible to participate in the trial. Also, patients who are unable to give consent or are moribund and not expected to survive more than a day are excluded.
Following mesenchymal stem cell infusion, the outcomes that are measured include a need for vasopressors, hypoxemia, cardiac arrhythmias and tachycardia, transfusion incompatibility, and cardiac arrest or death within one day of infusion. In addition, severe adverse events, ventilator-free days over the next 28 days, and vasopressor use over the next 28 days is also tracked. A note is also made of how many days the study participant was ICU-free as well as mortality rate 60 days following randomization.