Manufacturing / formulation advantages
Manufacturing to cGMP standards is often a major barrier to the successful translation of nanoparticle technologies. SNAPvax was purpose-built to overcome the fundamental challenges facing conventional nanoparticle technologies. Key innovations that enable improved manufacturing for facile, rapid clinical translation are summarized below.
Programmed drug loading in uniform nanoparticle compositions
SNAPvax comprises amphiphilic peptides that – upon addition of water – spontaneously assemble to uniform nanoparticles that have the same chemical composition as the underlying amphiphilic peptides. Thus, unlike conventional particle technologies that rely on empirical trial-and-error formulation processes, self-assembly allows SNAPvax particle compositions to be precisely controlled by chemically tuning the composition of the underlying amphiphilic peptides that give rise to the particles.
Through chemical programming, SNAPvax can be designed to ensure 100% antigen loading efficiency resulting in up to 60–70% antigen weight by mass. In contrast, conventional PLGA and liposomal particles rely on empirical formulation processes that can lead to variable and low peptide antigen loading.
Chemically defined molecules facilitate manufacturing and development
Conventional nanoparticle technologies often have variable properties that cause regulatory challenges. SNAPvax comprises chemically defined amphiphilic peptides that are amenable to simple chemical characterization techniques, e.g., HPLC and mass spectrometry for key purity and identity release tests.
Uniform nanoparticles
Conventional nanoparticle vaccine technologies require laborious processes (e.g., extrusion) to control particle size. In contrast SNAPvax amphiphiles spontaneously self-assemble into uniform (i.e., low polydispersity) nanoparticles upon addition of water. An example of a SNAPvax particle size distribution plot is shown here.
Sterile filtration without material loss
Sterile filtration is required for injectable drug products for pharmaceutical use. However, this critical step in pharmaceutical manufacturing is often overlooked early in drug development and many promising nanoparticle drug delivery technologies face major challenges including failure due to clogging of filter membranes and/or massive material loss.
SNAPvax comprises uniform 20 nm particles that can be sterile filtered without material loss, addressing an otherwise major problem for manufacturing nanoparticle vaccines.
Long-term stability in aqueous buffer at room temperature
SNAPvax comprises peptides that are highly stable in aqueous buffer during manufacturing and storage. The data below shows that SNAPvax in aqueous buffer (i.e., PBS, pH 7.4) undergoes no changes when sitting out at room temperature (RT) for 1 month, providing significantly enhanced stability over vaccine technologies that require -80C storage conditions. SNAPvax has been shown to be stable for at least 3 months at room temperature and is expected to have stability > 2 years when frozen.
