Novel matrix sustained-release tablet and preparation method thereof

Abstract

The invention relates to a novel long-acting sustained-release preparation and a preparation method thereof, in particular to a matrix sustained-release tablet with a controlled retardant layer and a preparation method thereof. The invention enables the matrix sustained-release tablet to be changed from the traditional single-layer tablet core structure to a double-layer structure including a drug containing layer and the controlled retardant layer by adding the controlled retardant layer to the structure of the traditional matrix sustained-release tablet, can also control the time of the retardant layer playing a retardant role by controlling the dissolving or corroding time of the retardant layer through predesign, very efficiently control the drug release and reduce the burst release and the late residuals, thereby obtaining excellent release effect.

Description

Technical field [0001] The invention belongs to the field of medicine, and relates to a novel matrix sustained-release tablet, in particular to a matrix sustained-release tablet with a controllable retardation layer. Background technique [0002] After nearly 50 years of development, oral drug sustained-release and controlled-release pharmaceutical preparations have become an important direction for the development of domestic and foreign pharmaceutical products. At present, there are more than 200 varieties of such preparations on the market abroad with more than 500 specifications. In 2008, the global market for oral sustained and controlled release preparations exceeded US$30 billion. [0003] The preferred dosage form of sustained-release pharmaceutical preparations is tablets. At present, the most widely used in the world is the use of hydrophilic gel matrix tableting technology to make hydrophilic gel matrix tablets. When producing such sustained-release tablets, the activ...

AI Technical Summary

Problems solved by technology

For example, venlafaxine hydrochloride, due to its exceptionally excellent water solubility (measured solubility can reach 1.5g / ml), even when the sustained-release material accounts for 60% of the weight of the entire tablet, the 2-hour release is still close to 40%. , for a preparation that requires 24h sustained release, it is obviously faster

[0012] 2. The release mechanism is single, and the release process control method is lacking: the release characteristics of the hydrophilic gel matrix of general water-soluble drugs are diffusion + erosion type, and they are of this type throughout the drug release process, so the drug is in the first-order or false state. First-order rate release, that is, the release rate decreases significantly with time, and the release rate is quite slow at the end of the release period

Since the main drugs are released in the first half of the entire release time (>70%), and most of the drugs are eliminated at the first-order rate, the rate of drug elimination from the peak concentration is much faster than that of matrix sustained-release tablets. The release rate of the drug in the later period, and thus unable to maintain the effective blood drug concentration in the later period of drug administration

For example, the commercially available venlafaxine hydrochloride sustained-release tablets release less than 10% of the drug in the second half of 12-24 hours. It is difficult to maintain the effective blood concentration of the drug, and it is difficult to ensure the sustained and stable drug effect

[0013] 3. Pressure has a great influence on the release of the matrix tablet: when the tablet is under less pressure, the porosity of the matrix increases, which increases the water absorption rate and dissolution rate of the matrix, and accelerates drug release; when the pressure is too high, The porosity of the skeleton is over-compressed, the density of the skeleton tablet increases, and the rate of water absorption on the tablet surface slows down, resulting in slow drug release. Therefore, it is necessary to continuously test to find a suitable pressure to ensure the release effect, which leads to waste and efficiency in industrial production. low

For example, the WO2007 / 123021 patent applied by Nippon Soda Co., Ltd provides a method of using different viscosity of the hydrophilic gel matrix material to control the initial release and reduce the residue of the tail release. It is found that this method is suitable for moderate water solubility However, for drugs with high water solubility, the low-molecular-weight hydrophilic gel material dissolves quickly, and the gel layer formed has a low viscosity and cannot effectively control the long-term effect of the drug. Release (24h)

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