A Methodical Approach for Reformulating Dutasteride Softgel Capsules into Hard Gelatine Capsules

This poster has been presented at the 15th World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology, which took place in Prague, Czech Republic.

INTRODUCTION

In this study, we demonstrate the feasibility of converting a liquid SEDDS formulation into solid SEDDS by absorbing an optimized lipid-based formulation (LBF) with a solubilized model compound (Dutasteride) on SYLOID® XDP 3150 as an inert silica gel-based carrier system.

Dutasteride served as a model compound. This API is used in medications for the treatment of benign prostatic hyperplasia and is classified as a BCS class II drug, i.e. poorly soluble but well permeable through biological membranes.

1 – API solubility screening

Evaluation of the most suitable lipid-based excipient as the basis for further formulation development. From the tested lipid materials Capryol® PGMC, Capmul® MCM and Capryol® 90 showed the highest solubility.

2 – Basic formulation design

The two basic formulation LS-1 and LS-2 contained only four ingredients: the API, Capmul® MCM rep. Capryol® 90, BHT and a silica gel-based carrier (SYLOID® XDP 3150). Release from these two formulations was significantly slower than from the benchmark and none of them achieved 100% release after 120 min.

3 – Liquid vs. Solid formulation

Comparison of the liquid formulation base (without the carrier), however, demonstrated faster dissolution than the marketed formulation.

4 – Variation of loading ratio

The loading ratio (liquid: solid) was varied over a range of 1:1 to 1:3. Although a loading ratio of 1:2 showed the best release results, it fell behind the release rate of the benchmark. However, like the benchmark, 100% release was achieved after 120 min.

5 – Effect of additional surfactants/ solubilizers

Further acceleration of the release could be achieved by modifying the formulations using surfactants and solubilizers as additional components using a combination of Transcutol® HP and Tween® 80 in two different fractions (Formulations D-1 and D-2) and at a loading ration of 1:2 (liquid: solid). Both formulations demonstrated faster release (95-97% after 15 min) compared to the marketed formulation (48%).

6 – Optimization of loading ratio and final formulation

We further modified the formulation in the next step, altering the loading ratio from 1:2 to 1:1 while maintaining the composition of the liquid phase. The modified formulation D-2A performed slightly worse than formulation D2 after 15 minutes of dissolution time (82.6% vs. 97.1%) but still significantly better in terms of release kinetics than the marketed formulation (48%). After 30 min, the difference in percentage of the released API (D-2A vs. D-2) is less than 2%.

7 – Stability testing of the optimized liquisolid systems

The formulation D-2A from the former stage was subjected to a 6-month stability study under accelerated conditions (40°C, 75% r.h.). Release profiles were recorded at t=0,3 and 6 months.

CONCLUSION AND OUTLOOK

The study successfully demonstrated that Dutasteride softgel formulations can be converted into solid SEDDS using mesoporous silica carriers without compromising dissolution or stability. The optimized formulations are suitable for hard gelatine capsules and offer improved handling and stability. This approach may be applicable to other softgel formulations, enabling broader use of solid SEDDS in oral drug delivery.

See the full poster on A Methodical Approach for Reformulating Dutasteride Softgel Capsules into Hard Gelatine Capsules here

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Source: Dinesh Guntupally; Tirumalesh N.; Joachim Quadflieg, Grace, poster: A Methodical Approach for Reformulating Dutasteride Softgel Capsules into Hard Gelatine Capsules

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