Mesoporous Silica Nanoparticles-Based Bilayer Tablets: A New Strategy for Co-delivery of Velpatasvir and Sofosbuvir

Abstract

Herein, we developed novel bilayer tablets based on velpatasvir (VLP) and sofosbuvir (SOF)
loaded mesoporous silica nanoparticles (MSNs) for possible treatment of hepatitis C. Direct compression
was employed to develop immediate release layer (IR) of VLP loaded MSNs (VLP-MSN) and the SOF loaded
MSN (SOF-MSN) formed the sustained release layer (SR) of bilayer tablet. To control SOF release, SOFMSNs were functionalized with 3-aminopropyl-triethoxysilane (APTES) and compressed with hydroxypropyl methylcellulose (HPMC). Bilayer tablets exhibited quality attributes within the compendial range.
Scanning electron microscopy (SEM) confirmed the intact MSN in both layers while Fourier transform
infrared spectroscopy (FTIR) ruled out drug-silica-polymer interactions. X-ray diffraction (XRD) analysis
and transmission electron microscopy (TEM) confirmed the ordered 2D hexagonal mesoporous architecture; moreover, XRD also indicated that both drugs were entrapped in pores of MSN in amorphous form.
These bilayer tablets released VLP in one hour, whilst SOF was released in controlled manner upto twenty
hours. Thus, stable nano-based bilayer tablets could open new prospects for the treatment of hepatitis C.
They would not only address intrinsic issues of drugs but could also provide optimum therapeutic effects
with minimum side effects