Additive Manufacturing with 3D Printing: Progress from Bench to Bedside.

Three-dimensional (3D) printing was discovered in the 1980s, and many industries have embraced it, but the pharmaceutical industry is slow or reluctant to adopt it. Spiritam® is the first and only 3D-printed drug product approved by FDA in 2015. Since then, the FDA has not approved any 3D-printed drug product due to technical and regulatory issues. The 3D printing process cannot compete with well-established and understood conventional processes for making solid dosage forms. However, pharmaceutical companies can utilize it where mass production is not required; rather, consistency, precision, and accuracy in quality are paramount. There are many 3D printing technologies available, and not all of them are amenable to pharmaceutical manufacturing. Each 3D technology has certain prerequisites in terms of material that it can handle. Some of the pertinent technical and regulatory issues are as follows: Current Good Manufacturing Practice, in-process tests and process control, and cleaning validation. Other promising area of 3D printing use is printing medications for patients with special needs in a hospital and/or pharmacy setting with minimum regulatory oversight. This technology provides a novel opportunity for in-hospital compounding of necessary medicines to support patient-specific medications. However, aspects of the manufacturing challenges and quality control considerations associated with the varying formulation and processing methods need to be fully understood before 3D printing can emerge as a therapeutic tool. With these points in mind, this review paper focuses on 3D technologies amenable for pharmaceutical manufacturing, excipient requirement, process understanding, and technical and regulatory challenges.