Senior Scientist Merck Co & Inc Metuchen, New Jersey
Islatravir, a highly potent nucleoside reverse transcriptase translocation inhibitor, has great potential to be formulated as polymer-based implants using ethylene-vinyl acetate (EVA). Microstructures of the implant revealed by X-ray computed tomography suggests drug release primarily depends on the open channels that are formed in the polymer matrix. Therefore, the measurement and quantification of EVA crystallinity is of great importance. Herein, we describe the systematic analysis of the factors affecting the EVA crystallinity in islatravir implants. Differential scanning calorimetry revealed that BaSO4 and API loading inhibited and promoted EVA crystallization, respectively. Dynamic mechanical analysis showed the storage modules of the implant is positively correlated to drug loading. After γ-irradiation, the crystallinity of EVA in implants became less prone to annealing on storage. These findings provide insights for understanding the factors affecting the crystallinity, mechanical properties, physicochemical properties and the stabilities of the EVA polymer matrix within the islatravir implant.
Learning Objectives:
Upon completion, participant will be able to demonstrate the comprehensive analysis of factors affecting the polymer crystallinity in polymer-based implant formulation.
Upon completion, participant will be able to define the key factors to consider for the analysis of implant formulation and stability.
Upon completion, participant will be able to describe how the physiochemical property of polymer excipient in implant affect the stability and drug release of the implant.
