low-resourced regions: microsampling makes albendazole research smarter and simpler
The Swiss Tropical and Public Health Institute is at the forefront of important research using Volumetric Absorptive Microsampling (VAMS®) technology and Mitra® microsampling devices in low-resourced regions. Recently, it tested Mitra® devices against more traditional Dried Blood Spot (DBS) cards in pediatric PK studies in rural Côte d’Ivoire.
Now, Swiss TPH’s helminths team, including Dr. Daniela Hofmann, is performing new work using Mitra® devices, including a study on evaluating different doses of albendazole to treat soil-transmitted helminths (STH).
"Albendazole is one of the very few medications listed on the WHO list of essential medicines to treat parasitic worm infections," says Dr. Hofmann. "In children, preventative chemotherapy, consisting of an annual or biannual single dose of albendazole at 400 mg, is recommended as a public health intervention where baseline prevalence of soil-transmitted infection is 20% or more."
To do her work, Dr. Hofmann travels to remote areas of the world to treat parasitic worms and takes blood sample donations to optimize future treatment for affected groups.
The study design is along similar lines to its earlier PK studies. "The research we are doing now follows an identical workflow as compared to earlier studies," says Hofmann. "Yet we are constantly interested in investigating the potential of novel and old anthelmintic drugs against different worms."
Once an LC-MS method is validated and a satisfactory correlation has been shown between samples obtained through venous blood sampling and dried blood microsampling, dose-finding PK studies in endemic regions (Cote d'Ivoire, in this case) are initiated.
"For a subgroup of the patients, finger-prick samples of blood were taken with Mitra® devices at defined time points," Dr. Hofmann says. "These samples lay the groundwork in evaluating and proposing improved doses and dosing regimens of albendazole in the treatment of STH."
Doing this sort of work in low-resourced regions poses unique challenges:
- Limited space and infrastructure: "Decreasing the total amount of material used, as well as being able to store blood samples in a simple and fast way, improves the workflow tremendously," says Dr. Hofmann. "Mitra® devices can be packed away immediately, do not require cooling or freezing, and are quite robust for handling and protected from dust, dirt, or spillover, and are thus very ideal."
- Low hygiene standards: "The absence of a clean facility or hospital increases the risk of infection doing venous blood sampling," Dr. Hofmann says. Here, too, VAMS® provides clear advantages.
- Language barriers: "It might happen that the study coordinators and nurses do not share a common language," says Dr. Hofmann. "It is important to have a simple tool to withdraw blood. The use of Mitra® devices can be illustrated and demonstrated easily and is very intuitive for most people."
With the use of VAMS® in work such as performing PK studies or therapeutic drug monitoring in low-resourced regions, "the whole analytical pipeline becomes more efficient and solid pharmacological studies that take place in marginalized areas become more feasible," Dr. Hofmann says. "What I like the most about using Mitra® is that it is very patient-friendly and nurse-friendly. It is easy and intuitive to handle and does not scare patients away from donating their blood."