“MCC SANAQ®burst”—A New Type of Cellulose and its Suitability to Prepare Fast Disintegrating Pellets

A comprehensive review on pharmaceutical excipients

The effectiveness of pharmaceutical drugs depends not only on their active components and manufacturing processes, but also on the role played by pharmaceutical excipients. The traditional definition of excipients as inactive and cost-effective substances has evolved significantly. They are now recognized as essential elements of drug formulations, constituting 80-90% of the final product. The rapid advancements in delivery systems, along with scientific, regulatory, financial and technological developments in biopharmaceutics, have generated renewed interest in the use and functionality of excipients, especially in solid dosage forms. This review focuses on the categorization of excipients according to the International Pharmaceutical Excipient Council (IPEC) and the establishment of guidelines for evaluating the safety of a new proposed excipient.

Approaches to developing fast release pellets via wet extrusion-spheronization

Microcrystalline cellulose (MCC) is widely regarded as the excellent choice to manufacture pellets via wet extrusion-spheronisation (ES) process due to its excellent water uptake capability, water holding capacity, desirable rheological properties, cohesiveness and plasticity etc. Nevertheless, in spite of all these advantages, limitations associated with the application of MCC also have been reported. The most prevailing limitation is prolonged or incomplete drug release profile due to the lack of disintegration as pellet contracts significantly during the drying process, especially when in combination with poorly soluble drug at a high level. This characteristic limits the application of MCC in immediate release formulations. Over the years, many approaches have been tried to overcome this disadvantage, such as modifying MCC, incorporation of superdisintegrant, increasing the porosity of pellet, partial or complete substitution for MCC, enhancing the solubility of poorly soluble drug (e.g. solid dispersion, self-emulsifying drug-delivery system), etc. In this review, we will provide an updated and integrated discussion of current approaches to prepare fast release pellets via wet ES.

Production and characterization of pellets using Avicel CL611 as spheronization aid

PURPOSE

The study looked into the feasibility of producing pellet using Avicel CL611 as spheronization aid by the extrusion/spheronization technique.

METHODS

Pellets were formulated to contain either 20% or 40% Avicel CL611 and lactose monohydrate as the other sole ingredient. Water is used as liquid binder. Quality of pellets and extrudates were analyzed for size distribution, shape, surface tensile strength and disintegration profile.

RESULTS

More water was needed when higher Avicel CL611 fraction was used during the production of pellets. The pellets of larger size were obtained by increasing the water content. Pellets with aspect ratios of ∼1.1 were produced with high spheronization speed at short residence time. Higher tensile strength was achieved when increasing the water content and the fraction of Avicel CL611 during pellet production. These pellets also took longer time to disintegrate, nonetheless all the pellets disintegrated within 15 min. A positive linear relationship was obtained between the tensile strength and time for pellets to disintegrate.

CONCLUSION

Strong but round pellets that disintegrate rapidly could be produced with Avicel CL611 as spheronization aid using moderately soluble compounds such as lactose.

Miniaturization in pharmaceutical extrusion technology: feeding as a challenge of downscaling

In recent years, extrusion technology has shifted the focus of pharmaceutical research due to versatile applications like pelletization, bioavailability improvement or manipulation of solid-state properties of drugs, continuous granulation, and the development of novel solid dosage forms. Meanwhile, a major effort has been devoted to the miniaturization of equipment in pharmaceutical extrusion technology, particularly with regard to the requirements of the development of new chemical entities and formulations. In the present study, a lab-scale twin-screw extruder was investigated in order to determine the limitations imposed by the feeding systems. The wet extrusion process was considered as challenging because both a powder and a liquid feeder have to be considered. Initially, the accuracy and uniformity of the powder and liquid feeder were tested independently of the extrusion process. After modification of the powder feeder, both feeders were investigated in conjunction with extrusion. Based on this, an optimization of the liquid feeder was required and completed. Both feeder modifications reduced the variability of the moisture content in the extrudates 10-fold. This led to a reliable small-scale extrusion process.