Direct comparison of SAHDA vs BRPT vs AAV.

It is estimated that ~2 billion people worldwide cannot afford even basic medicines. Bioreactor-produced recombinant protein therapies (BRPTs), among the world’s most-expensive medicines, have revolutionized treatment of a wide-spectrum of human-diseases, particularly the ~ 7,000 incurable, rare human single-protein, monogenic-deficiency diseases. Currently, BRPT are limited by toxicity, immunogenicity, short protein T1/2s and high-cost, creating a worldwide access-gap between those who can afford BRPTs versus those who cannot. Fabry disease (FD) is a monogenic deficiency disease caused by pathogenic-variants of the galactosidase-a (GLA) gene. FD damages heart, kidneys, CNS, gastrointestinal tract, and eyes. State-of-the-art anti-FD therapy, hGLA enzyme-replacement-therapy (ERT), requires bi-weekly IV infusions lifelong, costing ~ $200,000 per-patient per-year. High-lifetime costs can cause significant numbers of FD patients to permanently discontinue hGLA-ERT, thereby accelerating FD progression, which can lead to premature-death. Subcutaneously administered plasmid DNA alone has not been previously reported to transfect subcutaneous fat. Here we show one Subcutaneous Administration of HEDGES DNA vectors Alone (SAHDA) encoding the wildtype hGLA protein safely produces durable hGLA serum protein levels in the 1–10 ng/mL normal human hGLA range in immunocompetent mice. Unexpectedly, one administration of a highly-optimized SAHDA version encoding hGLA produced durable, ~ 100-fold higher hGLA serum protein levels than the 10 ng/mL high-normal human level. Importantly, components of the SADHA platform can be simply-modified to control the level and duration of hGLA serum protein-levels produced over a broad temporal-range in mice. Furthermore, one SAHDA-based administration of a HEDGES DNA-vector encoding a highly-neutralizing anti-SARS-CoV-2 monoclonal antibody (mAb) safely produces long-term protective serum mAb levels in immunocompetent-mice. SAHDA offers multiple advantages over BRPT, including not requiring an intact cold-chain and being readily freeze-dried. This combination enables SAHDA’s rapid deployment, then prolonged storage at ambient temperatures, even in equatorial-areas worldwide. SAHDA can readily be self-administered worldwide. It also obviates severe intravenous-infusion reactions. Taken-together, SAHDA may more effectively-, safely-, durably-, and cost-effectively-treat a spectrum of now poorly-treatable diseases worldwide.