DRUG STABILITY STUDY BASED ON L-DOPA

The quality, pharmacological activity and safety of medicinal products during storage directly depend on their ability to maintain properties within the limits established by regulatory documentation for a certain period under proper storage and transportation conditions, i.e. from its stability. Stability is one of the key requirements for medicines. Stability data are an integral part of the registration dossier. Based on the results of the stability study, the expiration date is determined, the materials used and the type of primary and secondary packaging are selected, the storage conditions of the medicinal product are determined, which are indicated in the regulatory documentation and in the instructions for medical use, and also placed on the packaging. Moreover, in the process of pharmaceutical development, the stage of stability studies can serve as the final element in the selection of drug candidates in order to select the optimal composition and conduct further research. As a result of the study of the stability of 3 series of different composition of nasal drops of a drug based on DOPA-PC, which is a pharmaceutical composition containing an amino acid (3,4-dihydroxy-L-phenylalanine, levodopa, L-DOPA) as an active ingredient, distributed in a polymer matrix based on a biodegradable copolymer of lactic/glycolic acids (polylactide glycolide, PLGA 50/50), the optimal composition of the drug was selected, the quality indicators of which did not go beyond the requirements of the draft specification. The shelf life of drugs of "accelerated aging" was calculated at a temperature 5 ± 3 °C, which was 3 years. Deviations of quality indicators from the draft specification at a storage temperature of 25 ± 2 °C in a series of samples of the drug were observed from the 6th month, which guarantees stability for up to six months if the temperature regime is violated by 5 ± 3 °C. The results obtained during this experiment will be taken into account in the development of the drug specification.