Interview with an Expert: Dr Alvaro Goyanes of FabRx
One of the most intriguing developments in additive manufacturing in recent years has been in the pharmaceuticals sector: the use of 3D printers to generate medication in tablet form. We were honoured to sit down with one of the pioneers of this technology, Dr Alvaro Goyanes, to discuss its inception, the progress it has made, and what we should expect from his ongoing research at FabRx in the years to come.
How did you originally become interested in 3D printing?
3D printing is now widely used to create many different types of objects with a great variety of materials. I think almost everyone is aware of this technology nowadays. Even if you do not use 3D printing at work or in your daily life, an increasing number of objects are created by 3D printing every day.
In my case, the first 3D printer I used was a fused deposition modeling (FDM) printer from Makerbot at University College London (UCL) School of Pharmacy. The printer was originally purchased to manufacture customised lab equipment and consumables for research, reducing costs.
What led to the idea of using 3D printing to create medicine?
One of the founder partners of FabRx, Prof. Simon Gaisford, leads a research group at UCL School of Pharmacy which focuses on the use of ink jet printing to prepare medicines. For many years Prof. Gaisford and his group have been preparing different types of inkjet-printed medicines, mainly films for oral and buccal delivery and patches for topical drug delivery. Inkjet printing is a two-dimensional printing technology (the same type of printer that everybody has at home or work) that requires a substrate to print onto, e.g. waffle or film. The idea of printing without substrate came up naturally; we wanted to manufacture whole formulations by ourselves, and 3D printing allows manufacturing of whole 3D-printed tablets (printlets), incorporating any drug without using a substrate.
What were the key challenges when you first started exploring this technology?
The main problems were that the printers we used were not designed for printing medicines. Also, the materials normally used in 3D printing were not appropriate for human consumption, as most of them were toxic. From the start, we also observed degradation of the drugs during the printing process and what makes the process unsuitable for pharmaceutical applications.
To solve these issues, we had to evaluate the use of pharmaceutical-grade materials within the 3D printers, and also adapt and modify the printers to work with these materials. More research is required into new materials to improve the technology, but current printing of 3D medicines does not depend on it. In the pharmaceutical field, we have been making tablets by compression for more than a century and the materials and technology we use now are not the same as those used in the beginning. We are at the start of a new stage, so there is room for improvement.
Of the different printing technologies you are currently exploring at FabRx, how would you describe their respective advantages/disadvantages?
At FabRx, we have specialist experience in using all the 3D printing technologies available in pharmaceutics, but we focus particularly on fused deposition modelling (FDM), material extrusion, selective laser sintering (SLS) and stereolithography (SLA). Each technology has advantages and disadvantages, but selection of the technology is made according to the characteristics of the printlets that we want to manufacture, e.g. fast dissolving tablets, controlled release tablets, chewable formulations, orodispersable tablets. In general, printlets are novel drug formulations that achieve personalised dose and controlled drug release profiles which can be tailored to the individual needs of each drug and that cannot readily be prepared by other manufacturing methods. Expertise in formulation development and knowhow in 3DP technology and drug-excipient characteristics are the main skills for selection of the best 3D printing technology for each application. In general, FDM printing is seen as the most promising technology for the preparation of personalised medicines at the dispensing point, e.g. hospitals or pharmacies, but obtaining a filament loaded with the drug that is used as starting material in FDM makes the whole 3D printing process challenging.
What recent advances in 3D printing materials and technology are you currently most excited about?
3D printing systems evolve very fast and the cost is reducing. Nowadays, 3D printing offers the possibility of creating a personalised medicine system through automated control over drug dose and is suitable for both low and high drug concentrations. Furthermore, it is possible to incorporate multiple drugs within one printlet to make fixed-dose combinations. Selection of the excipients or the dosage form design means the time of release and/or the release kinetics of each drug can be finely tuned.
We have recently published a paper on the use of SLS printing in pharmaceutics. Prior to this publication it was not thought possible to use a laser based 3D printing system to manufacture printlets without degradation of the drugs. However, we have proved that this is now possible.
How do you see the use of 3D printing for pharmaceuticals evolving in the near future?
As new drugs are developed that have increasing potency and differential effects within populations, there is a need to consider new manufacturing methods and novel supply chains to realise the paradigm of personalised medicines. Nowadays, medicines are usually manufactured in large-scale processes, which limits the range of dose strengths available. 3D printing (3DP) has potential as a point-of-dispensing manufacturing technique but current technology cannot be used to manufacture medicines for human use. In our view, 3DP technology will be rapidly developed, optimised and adapted to pharmaceutical manufacture. The technology will allow fabrication of individual tablets to pharmaceutical quality standards and will enable the dose in each tablet to be verified with in-situ analysis — the key legal requirement for a medicine to be dispensed.
In the near future, for some specific treatments, pharmacies will have 3D printers and print out drugs tailor-made for patients on the spot, but I can imagine in the far future a scenario in which the GP will e-mail the prescription to your 3D printer at home.