Homology Medicine Inc, a gene editing company based in Massachusetts, USA, has announced a $100M IPO on the US NASDAQ. The company uses its technology genome editing platform based on homologous receombination and delivered by AAV to develop treatments for a number of disorders. A Novemebr 2017 investment of $35M in Homology by Novartis AG (NYSE:NVS; SIX:NOVN) was focused on the development of AAV treatments for ophthalmic disease and a hemoglobinopathy disease. The ophthalmic investment had followed on an earlier vote of confidence by Noovartis with a n $83.5 M investment in Homology’s Series B financing round.
According to Homology Medicine Inc., the company’s commercial advantage is “based on groundbreaking science that harnesses the naturally occurring process of homologous recombination, the cells’ natural mechanism for gene repair. This non-nuclease-based approach offers substantial benefits over current gene editing and gene therapy approaches, utilizing proprietary vectors that allow for precise and efficient in vivo and ex vivo gene editing and superior biodistribution across many tissue types for gene therapy.” The collaboration between Homology and Novartis will involve a specific focus on AAV and CRISPR gene editing technology to target particular pathways in certain ophthalmic diseases. Recent commercial success in the US on gene therapy treatment for a form of Leber’s congenital amaurosis (LCA) have stimulated large pharma to look closely at the area. Ophthalmic disease is a natural beneficiary of this commercial activity as the eye is ideally suited to AAV gene therapy strategies, being an immune privileged enclosed chamber readily accessible through sub-retinal injection.
CRISPR technology is a relatively recent gene editing tool, formally referred to as “clustered regularly interspaced short palindromic repeats” or “CRISPR/Cas9”. The technology has emerged from research into prokaryotic immune defence systems. Observations in a number of prokaryotic and archaebacteria in the late 1980s identified repetitive sequences originally reported as an unusual set of 29 nucleotide repeats interspersed with five intervening 32 nucleotide runs, seemingly without any discernible function. Over a period of 10+ years, as increasing numbers of DNA sequences were deposited in the public databases, a growing number of similarly structured repeat sequences, interspersed with unusual patterns, were reported from several different bacterial and archael strains. Subsequent in silico analysis characterized such families of repetitive DNA sequences within archaea and bacteria but absent from eukaryotes and viruses. Spacer sequences separating the individual direct repeats appeared to have a phage associated origin. Coupled to this were separate observations that viruses were unable to infect cells that carried spacer sequences corresponding to their own genomes. In essence, the system as a whole appeared to represent an un-expected and sophisticated immune system for prokaryotes, essentially a new mechanism that provided an immune memory of previous phage infections and facilitated rapid clearing of subsequent phage invasions that had previously infected the cell. Multiple research groups worldwide have now expanded, harnessed and developed the technology to act as a gene editing tool – engineered sequences can be introduced into cells to target specific sequences for deletion, coupled with replacement by sequences of choice. Homology Medicine Inc. is one company among many that is now focused on converting these original findings into therapeutic tools and recent support from large pharma are clear indication that the field is now moving closer to clinical application. Homology’s IPO is a further step in under-writing the rapid acceleration of the technology to market, an acceleration which is likely to have a number of positive impacts for a variety of ophthalmic diseases.