RESUMEN
Although silicon is more commonly associated with computer chips than with drug delivery, with the discovery that porous silicon is a viable biocompatible material, mesoporous silicon with pores between 2 and 50 nm has been loaded with small molecule and biomolecule therapeutics and safely implanted for controlled release. As porous silicon is readily oxidized, porous silica must also be considered for drug delivery applications. Since 2010, only a limited number of US patents have been granted, primarily for ophthalmologic and immunotherapy applications, in contrast to the growing body of technical literature in this area.
Asunto(s)
Portadores de Fármacos/química , Patentes como Asunto , Preparaciones Farmacéuticas/administración & dosificación , Silicio/química , Bibliotecas de Moléculas Pequeñas/administración & dosificación , Sistemas de Liberación de Medicamentos/instrumentación , Humanos , Preparaciones Farmacéuticas/química , Porosidad , Bibliotecas de Moléculas Pequeñas/química , Propiedades de SuperficieRESUMEN
As a case study of patent coverage for a repurposed drug, Biogen Idec's approach for Tecfidera(®), an oral formulation of dimethyl fumarate, was analyzed. While mixtures of fumarates have been used for over 50 years to treat psoriasis, Tecifidera is approved for the treatment of relapsing-remitting multiple sclerosis. Biogen pursued claims to pharmaceutical formulations and useful doses for treating multiple sclerosis, an approach that is relevant to pharmaceutical lifecycle management in general. A survey of recent US, EP, and PCT patent applications indicate other companies are developing competing fumarate formulations. While it is possible to pursue secondary patents for compounds without composition of matter coverage, regulatory data exclusivity provides additional protection to delay competitors.