The Boston-based biotech Jnana Therapeutics just announced its launch with a US$ 50m Series A financing. Its focus will be to build the first discovery platform dedicated to targeting the solute carrier (SLC) family of transporters.
The SLC transporters is a family of more than 300 membrane-bound proteins that facilitate the transport of a wide array of substrates across biological membranes. The SLC transporters have important roles in physiological processes, ranging from the cellular uptake of nutrients to the absorption of drugs and other xenobiotics. Several classes of marketed drugs target SLC transporters, such as neurotransmitter transporters for instance. In addition, human genetic studies have provided powerful insight into the roles of more-recently characterized SLC transporters in both rare and common diseases, indicating a wealth of new therapeutic opportunities.
Most current drugs that modulate SLC transporters, as well as novel drugs in clinical trials, do so by inhibiting transporter activity:
Several diuretic drugs (to treat hypertension and heart failure) works by inhibiting the efflux of Na+, K+ and Cl- through the SLC12 transporters.
Some neuropsychiatric drugs works by blocking the uptake of monoamines (e.g. noradrenaline, dopamine and serotonin) through inhibition of the SLC6 transporters.
Other interesting therapeutic molecules include glucose transporter inhibitors, uric acid inhibitors and glycine transporter inhibitors. For instance, Johnson & Johnson’s Invokana (canagliflozin) is a marketed drug for type 2 diabetes that works by inhibiting the subtype 2 sodium-glucose transport (SGLT2).
On its corporate website (see here), Jnana refers to the SLC transporters family as the cell’s metabolic gate. A review article published in Nature in 2015 focussing on SLC transporters (see here) reveals that the sub-class of nutrient transporters could be the most therapeutically relevant. In oncology for instance, tumour cells have an increased demand for nutrients (owing to their rapid proliferation and growth), however, several nutrients transporters part of the SLC family have been implicated in diseases pathology.
The SLC family of transporters is amenable to modulation by small molecules, and this is precisely what Jnana is intending to do using its proprietary small molecule platform.
 SLC transporters as therapeutic targets: emerging opportunities; Lin, L. et al. Nat. Rev. Drug Discov. 2015, 14, 543-560.