The patent WO2019123269A1, titled Packaged modified release gamma-hydroxybutyrate formulations having improved stability presents innovative formulations and packaging methods designed to enhance the dissolution and chemical stability of gamma-hydroxybutyrate (GHB), a treatment for narcolepsy. Current GHB treatments, like XYREM®, require patients to wake up mid-sleep for a second dose, making this method cumbersome. This patent aims to develop a once-nightly, modified-release GHB form that maintains stability through advanced packaging, which controls relative humidity to ensure long-term effectiveness and prevent chemical degradation of GHB into gamma-butyrolactone (GBL).

Key Innovations:

  1. Modified Release Formulation: The patent includes an immediate and modified release component, both containing GHB or a pharmaceutically acceptable salt. The modified release form is designed to control the release of GHB over time, providing sustained therapeutic effects throughout the night without the need for a second dose. This formulation helps improve patient convenience and adherence to treatment.
  2. Stability Issues with GHB: GHB is highly hygroscopic and chemically unstable, which leads to degradation, especially in high humidity environments. Its instability results in the formation of GBL, a degradation product that reduces the drug’s effectiveness. The patent addresses these challenges by creating a formulation with stable dissolution profiles and chemical stability, even under stressful storage conditions (e.g., high temperature and humidity).
  3. Packaging Innovation: To further enhance the stability, the GHB formulations are packaged in a way that maintains a specific relative humidity range (29% to 54%) within the package. This careful control of humidity is crucial to prevent GHB from degrading into GBL. The packaging material has a low water vapor transmission rate, reducing moisture exposure and ensuring the drug remains stable over time.
  4. Hydrophobic Coating: The patent uses a hydrophobic coating (e.g., glyceryl tristearate, hydrogenated vegetable oil) and methacrylic acid copolymers for the modified release component. These coatings help control the release rate of GHB and protect it from moisture, ensuring a steady release and preventing premature degradation.
  5. Pharmaceutical Composition: The GHB composition in the patent includes varying ratios of immediate and modified release components. These compositions are tailored to provide a sufficient therapeutic dose while maintaining stability. The sizes of the particles and the specific formulation ratios (e.g., 40/60 to 60/40) are key factors in achieving the desired pharmacokinetics and release profiles.

The primary innovation lies in controlling the relative humidity within the packaging, alongside a modified release formulation with hydrophobic coatings to maintain the drug’s chemical stability and effectiveness. These advancements make GHB therapy more convenient by eliminating the need for a second nightly dose and addressing the stability challenges that have plagued previous formulations.

In this patent, CELLETS® play a crucial role as inert cores used in the formulation of modified release or the active or salts thereof. These starter spheres serve as carriers for the active ingredient by providing a surface for multi-layer drug layering. Their primary function is to ensure uniform drug distribution and control the release profile of GHB. The benefits include enhancing dissolution stability, maintaining the integrity of the dosage form over time, and helping to modulate the release rate of the drug for once-nightly dosing convenience. For these aspects, MCC starter sphere types where employed: CELLETS® 90, CELLETS® 100, CELLETS® 127. Glatt ProCell™ technique is used for spraying molten API.

Document information

Document Type and Number: (“Packaged modified release gamma-hydroxybutyrate formulations having improved stability”).
Kind Code: A1

Inventors:

Hervé GUILLARD

Disclaimer

This text was partly generated by chatGPT engine version GPT‑4o, on Oct 21, 2024. Image was generated with Adobe Firefly.