A UCL-led project dubbed ChromaDose aims to improve the delivery of chemotherapy drugs and reduce side effects for children with cancer.
The 30-month project, supported by the NIHR-funded London In-Vitro Diagnostic Co-operative, is focused on development of a bedside automated drug monitoring tool. The ‘ChromaDose’ device will allow for point-of-care testing of drug exposure in blood samples of children receiving anthracyclines — a type of medicine used in chemotherapy.
Drug exposure describes the concentration of medicine in the blood and is an important factor in determining whether the patient will experience severe side effects. Anthracyclines can cause heart problems in up to 65 per cent of children, most often due to dose-related cardiotoxicity.
Until now, the standard method for determining the dose of anthracyclines in children has been to use the patient’s weight and height. Due to inconsistencies in the way that medicines are processed by children of the same size, this can reduce drug safety and increase the potential for harmful side effects.
Currently, drug monitoring approaches are costly and suffer time delays, preventing the methods from being widely accessible. ChromaDose aims to change this by providing an affordable solution with rapid results. The applied prototype and design work is led by the UCL start-up Vesynta, and the team is working with a consortium of stakeholders including scientists, clinicians and children.
Dr Stefan Guldin, project lead and associate professor at UCL, explained how at the heart of the technology is a hermetically sealed cartridge which combines chromatographic separation with a densitometric fluorescent-based read-out. “Thin layer chromatography has been used for decades by chemists as a preferred method of separating chemical compounds,” he said.
“We’ve now taken this step further to allow thin layer chromatography [to be used] in a clinical environment, by making the cartridge hermetically sealed so all of the chemistries happen inside the cartridge and not openly. Crucially, our method also enables precise quantification of the target compounds by performing the analysis alongside various calibrants.”
The process will involve a blood sample taken by a nurse which will then be inserted into the ChromaDose machine. The machine will place blood samples on a silica plate and take a fluorescent photo to measure the amount of medicine in the blood, with higher amounts producing a brighter image. This would then allow the doctor or nurse to decide whether to adjust the dose.
ChromaDose’s hardware will be combined with a user-friendly software interface, with liquid handling and analysis carried out by the robot when the blood sample is inserted by a nurse. Guldin described the methodology as ‘very robust’, adding that the main engineering challenge lies in the autonomy of the machine’s components rather than accuracy of the quantification principle.
The team is currently working on quality assessment, ensuring the device meets necessary standards, and hopes to soon move on to clinical trials with an aim of widespread roll-out of the technology in roughly five years.