With $38 million in funding from a range of investors, Arrakis Therapeutics has formally launched to create a new class of drugs: small molecules that directly bind to RNA.
Led by biotech veteran Michael Gilman, Arrakis is chasing the vast number of “undruggable” targets that have frustrated the industry.
Medicinal chemists primarily design small molecules that bind to active sites on cellular proteins. But sometimes those pockets are inaccessible. Arrakis thinks it can access the vexing targets by going after the RNA transcripts for the protein, rather than the protein itself.
Compared to proteins, RNA is dynamic. “Let’s say a messenger RNA is floating around the cytoplasm,” Gilman explains. “It’s flip-flopping and sampling lots of different structures.” The right small molecule could lock into an RNA structure and keep it from performing its duties.
To find those small molecules, Arrakis’s founder and chief scientific officer, Russell C. Petter, an organic chemist who previously worked with Gilman at Biogen, developed two platforms: a bioinformatics tool for identifying sites on RNA where small molecules can latch and a set of chemical biology tools for validating the efficacy and selectivity of small molecules. Used in tandem, Gilman says, they should yield drug candidates.
Arrakis is focused on three therapeutic areas: neurology, oncology, and rare genetic disorders. Although the company has thus far relied on contract research organizations, it is now moving into labs in Waltham, Mass., “and will build out a strong bench-level scientific team,” Gilman says.