Release on Demand XWpharma’s Controlled Release Granulations for Water-Soluble Drugs

XWpharma Ltd. has filed a patent for pharmaceutical granulations with functional coatings that control the release of water-soluble active pharmaceutical ingredients from oral dosage forms. The invention addresses one of the fundamental challenges of oral drug formulation: managing how quickly a highly soluble drug is released after it is swallowed.

The Problem

Water-soluble drugs present a specific challenge in oral pharmaceutical formulation. Because they dissolve readily in the aqueous environment of the gastrointestinal tract, they are quickly absorbed – which for some drugs and dosing scenarios is exactly what is wanted, but for many others creates significant problems. Drugs that are absorbed too quickly reach high peak concentrations in the blood that may cause side effects or toxicity, then fall away before the next dose, creating periods of inadequate therapeutic coverage. This “peak-and-trough” pharmacokinetic profile is associated with reduced efficacy, increased side effects and reduced patient compliance.

Controlled release formulations address this problem by modifying the rate at which a drug is released from the dosage form, spreading absorption over a longer period to maintain more consistent blood levels. Controlled release technology is well established for many drug classes, but applying it effectively to highly water-soluble compounds is technically challenging. Because these compounds dissolve readily, conventional matrix-based controlled release approaches – where the drug is dispersed throughout a slow-dissolving polymer matrix – may not provide adequate control, since once any part of the matrix is wetted, the drug dissolves rapidly from that region regardless of the overall matrix dissolution rate.

A coating-based approach, where a functional coating surrounds an individual drug-containing core, provides better control because the coating serves as the primary rate-determining barrier. However, achieving consistent, reliable coating of individual granules – as opposed to larger tablet cores – at manufacturing scale, while maintaining the coating’s functional performance throughout the product’s shelf life, is a significant formulation science challenge.

What This Invention Does

XWpharma’s invention describes pharmaceutical granulations in which a functional coating surrounds a core that contains the water-soluble active pharmaceutical ingredient. The functional coating is designed to provide either immediate release or controlled release of the drug, depending on the coating composition and architecture specified.

The granulation format – producing many small coated particles rather than a single large coated tablet – offers several practical advantages. Granulations can be filled into capsules, compressed into tablets, or formulated into multiparticulate dosage forms that may offer better dose uniformity, more predictable gastrointestinal transit and the ability to combine different release populations in a single dosage form. For example, a combination of immediate-release and controlled-release granules in the same capsule can deliver an initial therapeutic dose quickly while also providing sustained drug levels over subsequent hours.

The core of each granulation contains the water-soluble drug, and the functional coating serves as the rate-controlling membrane. The composition of the coating determines its permeability to water and dissolved drug, controlling the rate at which drug diffuses out of the core into the surrounding fluid. By carefully selecting coating composition and thickness, the release rate can be tuned to achieve the desired pharmacokinetic profile for the specific drug and indication.

Key Features

Functional coating architecture. Each granulation comprises a drug-containing core surrounded by a functional coating that serves as the primary release-controlling element, providing more reliable control over highly water-soluble compounds than matrix-based approaches.

Water-soluble drug applicability. The invention is specifically designed for active pharmaceutical ingredients with high water solubility – a class of compounds for which conventional controlled release approaches often provide inadequate rate control.

Immediate or controlled release options. The functional coating can be formulated to provide either immediate release (maintaining the drug’s natural solubility advantage) or controlled release (modifying the dissolution profile for pharmacokinetic benefit), providing formulation flexibility.

Oral composition compatibility. The granulations are suitable for incorporation into oral pharmaceutical compositions, including capsules, tablets and other multiparticulate dosage forms.

Multiparticulate versatility. The granulation format allows multiple release populations to be combined in a single dosage form, enabling sophisticated pharmacokinetic profiles with a single oral dose.

Who Is Behind It?

XWpharma Ltd. is a pharmaceutical company focused on developing improved formulations of existing and new drug compounds. The inventor team – Sami Karaborni, Daniel M. Canafax, Jia-Ning Xiang, James Tien, Nicolas D. Kirkland and William W. Xiang – brings expertise in pharmaceutical formulation science, drug delivery and clinical pharmacology. The application is filed through Minter Ellison and is a second-generation divisional (divisional of AU 2024203801, itself a divisional of AU 2021292406), reflecting a sustained programme of formulation patent development tracing back to 2020.

Why It Matters

Controlled release formulation technology has been transformative for patient compliance and therapeutic outcomes across numerous drug classes, from cardiovascular medications to central nervous system drugs to analgesics. For water-soluble drugs specifically – which constitute a significant proportion of all pharmaceuticals in development and use – effective controlled release formulation can mean the difference between a drug with manageable side effects dosed once daily and one that must be taken multiple times a day to maintain therapeutic levels without causing toxicity.

XWpharma’s functional coating granulation approach addresses this challenge with a well-established coating-based platform applied to the specific problem of highly soluble compounds. If the coatings described in this patent deliver reliable, scalable controlled release performance across a range of water-soluble drugs, the technology could have broad applicability across XWpharma’s development pipeline and potentially as a licensed platform for other pharmaceutical companies dealing with the same formulation challenges.

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AU 2026201607 was published in the Australian Official Journal of Patents on 19 March 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.