3D-Printed Tablets: How Layer-by-Layer Scanning Catches Defects for QA

Xiaoling Li, professor of pharmaceutics, University of the Pacific and CSO, Triastek, connected with PharmTech at AAPS PharmSci 360 in New Orleans, which occurred from October 25-28, to discuss the move from conventional formulation to digital dosage form design starts with removing the tooling. Tied to his AAPS keynote on how additive manufacturing is changing pharmaceutical development, Li explains that 3D-printed tablets do not rely on a punch and die to set their external shape. Instead, design begins in computer-aided design software. “So whatever you can draw, you can design that dosage form,” he says.

That digital starting point reaches inside the tablet too. Li describes tablets with multiple compartments, each holding a different API with its own release kinetics. For single release profiles, he says, 3D printing can do whatever traditional methods do. The advantage shows up when several release modes and APIs must be combined, which conventional tableting finds very challenging or impossible. He compares the approach to snapping Lego pieces together, with one piece for zero-order release and another for delayed release, to form a single tablet.

On commercialization, Li says Triastek’s process depends on scaling out rather than scaling up, because printing one tablet uses the same mechanism as printing several thousand. “So it doesn’t really have a scale up issue,” he says.

On quality, Li notes that the conventional process analytical technology checkpoints carry over to continuous 3D printing lines. In addition, a laser light scanner monitors and records every printed layer, so a defect in a finished tablet shows up right away.

For a company’s first project, Li points to a challenging molecule or development problem and recommends starting with a feasibility study. “That would really help people to understand our technology,” he says.