Patent No. EP3421034 (titled "Composite Capsule Preparation Containing Tadalafil And Tamsulosin And Having Improved Stability And Elution Rate") was filed by Hanmi Pharm on Mar 31, 2017. The application was issued on Nov 16, 2022.
Capsule composite formulation containing both tadalafil and tamsulosin for treating erectile dysfunction and benign prostatic hyperplasia simultaneously. The formulation has improved stability and dissolution of both drugs compared to separate capsules. The key is coating the tadalafil part with a film layer containing PVA. This prevents interaction between tadalafil and tamsulosin when combined in a capsule. The PVA coating on tadalafil provides stability without affecting its dissolution. The tamsulosin part can have an enteric coating. The tadalafil part is a compressed tablet of granules with a mix of larger and smaller particles.

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