Direct Cyclodextrin Based Powder Extrusion 3D Printing for One-step Production of the BCS Class II Model Drug Niclosamide

Niclosamide (NCS) is a drug that has been used as an anthelmintic and anti-parasitic active principle for about 40 years. Recently, some studies have highlighted its potential in treating various tumors, allowing a repositioning of this drug. Despite its potential, NCS is a Biopharmaceutical Classification System (BCS) Class II drug, and is consequently characterised by low aqueous solubility, poor dissolution rate and reduced bioavailability, which limits its applicability. In this work, we utilize a very novel technique, Direct Powder Extrusion (DPE) 3D printing, which overcomes the limitations of previously used techniques (Fused Deposition Modelling, FDM) to achieve direct extrusion of pharmaceutical grade powder mixtures consisting of NCS, hydroxypropyl methylcellulose (HPMC, Affinisol 15 LV), hydroxypropyl-b-cyclodextrin (HP-β-CD) and polyethylene glycol (PEG) 6000. For the first time, direct printing of powder blends containing HP-β-CD was explored. For all tablets, in vitro dissolution studies showed sustained drug release over 48 hours, but for tablets containing HP-β-CD, the release was faster. Solid-state characterisation studies showed that during extrusion, the drug lost its crystal structure and was evenly distributed within the polymer matrix. All printed tablets exhibited good mechanical and physical features and guarantee stability of the drug content for up to 3 months. This innovative printing technique has demonstrated the possibility to produce personalised pharmaceutical dosage forms starting directly from powders, avoiding the use of filament used by FDM.