Rationale for NDDS
(1500):
NDDSs are being developed to overcome several limitations of conventional drug delivery systems. Although oral risperidone has superior efficacy to older antipsychotics and has remarkably less side effects (5), the greatest limitation with the use of risperidone for schizophrenia and bipolar disorder is non-compliance such as partial dosing or infrequent dosing by patients (6) Three quarter of all patients with schizophrenia are not compliant to their oral medications (5). Non-compliance is directly associated with more frequent schizophrenic episodes and consequently an increased likelihood of re-lapse and re-hospitalisation and increased duration of hospitalisation (7). In addition to the direct cost to …show more content…
Each particle in the white microsphere powder consist of small beads of microspheres loaded with a matrix of the polymer poly (d ,l -lactide-co-glycolide), PLGA, suspending the active ingredient risperidone (2).
The polymer PLGA is hydrophilic polyester, biocompatible and biodegradable to non-toxic products (lactic acid, glycolic acid, carbon di- oxide, and water). PLGA polymers demonstrate a well controlled and predictable release properties when degraded in the body. PLGA microspheres with particle size ranges from 100nm to 500µm show a loading level of 38.1%. This means each gram of PLGA microsphere is loaded with 381 mg of risperidone (2).
The clear and colourless diluent contains the surfactant polysorbate 20 to reduce the surface tension for easier reconstituting, the stabiliser sodium carboxymethyl cellulose to stabilise the micro suspension, sodium chloride and sodium hydroxide to adjust the pH, disodium hydrogen phosphate dihydrate, citric acid anhydrous and water for injections …show more content…
These patents have not expired yet and will expire in the next few years, starting of 5792477 and 5792477*PED which will expire in Nov 2, 2017 and closing by 6667061 expiring on Nov 25, 2020. The new patents include the same pharmaceutical ingredients, however Janssen Pharmaceutical apply each time to extend the patent by improving the delivery system invented and own by Alkermes Controlled Therapeutics, Inc. (9). RISPERDAL® CONSTA® was exclusive to the US market up to 2012
(1500):
NDDSs are being developed to overcome several limitations of conventional drug delivery systems. Although oral risperidone has superior efficacy to older antipsychotics and has remarkably less side effects (5), the greatest limitation with the use of risperidone for schizophrenia and bipolar disorder is non-compliance such as partial dosing or infrequent dosing by patients (6) Three quarter of all patients with schizophrenia are not compliant to their oral medications (5). Non-compliance is directly associated with more frequent schizophrenic episodes and consequently an increased likelihood of re-lapse and re-hospitalisation and increased duration of hospitalisation (7). In addition to the direct cost to …show more content…
Each particle in the white microsphere powder consist of small beads of microspheres loaded with a matrix of the polymer poly (d ,l -lactide-co-glycolide), PLGA, suspending the active ingredient risperidone (2).
The polymer PLGA is hydrophilic polyester, biocompatible and biodegradable to non-toxic products (lactic acid, glycolic acid, carbon di- oxide, and water). PLGA polymers demonstrate a well controlled and predictable release properties when degraded in the body. PLGA microspheres with particle size ranges from 100nm to 500µm show a loading level of 38.1%. This means each gram of PLGA microsphere is loaded with 381 mg of risperidone (2).
The clear and colourless diluent contains the surfactant polysorbate 20 to reduce the surface tension for easier reconstituting, the stabiliser sodium carboxymethyl cellulose to stabilise the micro suspension, sodium chloride and sodium hydroxide to adjust the pH, disodium hydrogen phosphate dihydrate, citric acid anhydrous and water for injections …show more content…
These patents have not expired yet and will expire in the next few years, starting of 5792477 and 5792477*PED which will expire in Nov 2, 2017 and closing by 6667061 expiring on Nov 25, 2020. The new patents include the same pharmaceutical ingredients, however Janssen Pharmaceutical apply each time to extend the patent by improving the delivery system invented and own by Alkermes Controlled Therapeutics, Inc. (9). RISPERDAL® CONSTA® was exclusive to the US market up to 2012