Clinical studies in silico
The concept of in silico studies, in which digital models of patient groups are built instead of real people, is a bit like how virtual populations are built in the computer game The Sims.
In silico research could revolutionize clinical research by reducing the time and cost of developing new medical devices and drugs, as well as reducing the harm to humans and animals during testing.
Virtual patient populations are created based on clinical databases reflecting age, gender and ethnicity. They also simulate the effects of the disease on the human body: for example, anatomical, physical, physiological and biochemical interactions. These models are then used to simulate the effects of medications and interventions.
An international team of researchers has studied whether the in silico study can repeat the results of three real clinical studies that evaluated the effectiveness of the so-called flow diverter used in the treatment of brain aneurysms.
The flow diverter initiates recovery
The flow diverter is a small flexible mesh tube installed in the aneurysm area using a catheter. The device directs blood along the blood vessel and restricts flow into the aneurysm cavity, initiating a clotting process that eventually cuts off the aneurysm from circulation.
A blood vessel with an aneurysm. Left: blood flows through an aneurysm; right: the installed device directs blood past the aneurysm.
To prove their concept, the researchers decided to check whether the results of their in silico study were consistent with the results of three large clinical trials of the effectiveness of flow deflectors.
"Participants" of the virtual study
The researchers built a virtual population using real patient data taken from clinical databases, emphasizing that anonymized virtual patients are very similar to patients who participated in real clinical trials of the flow diverter in terms of age, gender and aneurysm characteristics.
Then the researchers built a computer model that allowed analyzing the effect of the implanted device on the blood flow of each of the virtual patients. They were able to take into account different conditions for each patient, for example, normal or elevated blood pressure, and perform an analysis of subgroups of patients, for example, patients with large aneurysms or aneurysms on the branching of a blood vessel.
82 virtual cases were included in the in silico study.
109, 141 and 207 patients participated in traditional clinical trials, respectively. Approximately half of the participants had high blood pressure.
According to the results of the in silico study, 82.9% of virtual patients with normal blood pressure were treated with a flow diverter successfully. In traditional clinical trials, the proportion of patients who responded to treatment was 86.8%, 74.8% and 76.8%, respectively, which indicates that the in silico study repeated the results of traditional clinical trials.
Advantages of in silico research
The results of this work demonstrate the huge potential of in silico research, this approach was able to reproduce the results of traditional clinical trials faster and for less money.
During the in silico study, the researchers were also able to adapt the computer model to study other scientific issues. Thus, by modeling the physical parameters of blood flow and biochemical characteristics of blood clotting in aneurysms under various physiological conditions, the researchers were able to identify subgroups of patients with a higher risk of stroke: patients with larger complex aneurysms had a high risk of hemorrhagic stroke, and patients with hypertension had a higher risk of ischemic stroke due to thrombosis.
The ability to pre-analyze the operation of a medical device will allow biomedical engineers to optimize the design of the device and reduce the risks associated with treatment.
Article by A.Sarrami-Foroushani et al. The in-silico trial of intracranial flow diverters replicates and expands insights from conventional clinical trials is published in the journal Nature Communications.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the University of Leeds: 'Huge potential' in virtual clinical trials.