3D printing medicine for children

Toxoplasmosis is an infection caused by a parasite called Toxoplasma gondii, and it affects over 40 million people in the US and one billion people worldwide. While most healthy adults don't experience symptoms, the infection does pose serious risks for pregnant women and their babies.

If a pregnant woman contracts toxoplasmosis, the infection can pass to the unborn child, leading to severe complications like blindness, deafness, seizures, and intellectual disabilities.

In the US, toxoplasmosis is the leading cause of foodborne deaths because of the many ways that humans can contract the infection, for example, by eating undercooked meat or unwashed produce, or through exposure to cat litter or soil containing infected faeces. Although people with strong immune systems may not even realise they’re infected, young children and anyone with a weakened immune systems are at higher risk.

Currently, the only treatments for paediatric toxoplasmosis are expensive adult tablets that pharmacists must manually alter to make suitable for children. Unfortunately, this approach isn’t ideal, as compounded tablets can vary in quality, strength, and stability. Furthermore, these adult drugs come with a hefty price tag. For example, a single tablet of Daraprim, a common treatment for toxoplasmosis, costs roughly $790.

Dr. Mansoor A. Khan and Dr. Ziyaur Rahman from Texas A&M University are leading research on a solution to address the cost and quality challenges by using advanced 3D printing technology. The aim is to develop dose-flexible, child-friendly tablets that are specifically designed to treat paediatric toxoplasmosis. The research is being supported by a $3.1 million grant from the National Institutes of Health (NIH), and the team aims to create medication tailored for children – something that is urgently needed but not commercially available. By producing tablets using 3D printing, the researchers can adjust dosages more precisely according to a child’s changing size and weight  – this is essential in long-term treatments like toxoplasmosis as the course of treatment can last for a year or more.

This approach is part of a broader field of 3D-printed medicine, also known as biofabrication. Biofabrication in medical settings is something that allows for precise, patient-specific adjustments to be made to everything from personalised drug tablets to medical models and implants. The process often involves various printing technologies which are each suited to different medical applications. One example is Selective Laser Sintering (SLS), which is used to create child-friendly, dissolvable tablets by adjusting laser and material parameters for dose consistency and stability to allow for more accessible options for children who may struggle with traditional tablets. Other methods like extrusion-based printing and inkjet printing are also effective for layering ingredients to allow for controlled-release tablets – this is important for medications that need to be administered over time and without frequent re-dosing.

The printed tablets at Texas A&M will be assessed for important qualities like stability, safety, and how well the body absorbs them. Once perfected, the goal is to bring the 3D printing machines into hospitals to enable medical facilities to produce personalised doses on demand meaning that accessible, patient-focused treatments can be provided when they are needed.

Using a 3D printing medicine in a medical setting, namely for printing drugs, is not a one-off development, a similar 3D-printed drug development project has been producing tablets containing tenofovir disoproxil fumarate (TDF), an antiviral medication for HIV and hepatitis B. Like the toxoplasmosis treatment, these tablets are designed to dissolve in the mouth for ease of use and feature dose flexibility, which allows doctors to tailor treatments to individual needs. By using SLS, researchers have been able to control factors like tablet hardness, dissolution rate, and absorption into the body, achieving results equivalent to standard commercial tablets.

3D printing has come a long way since its initial inception, and it is great to see that we are at a point where it can address gaps in paediatric medicine. I think that we are only on the cusp of what is possible with 3D printing – today its medicine and bone, tomorrow – limb regeneration.