Alexander S. Kurdyumov

Importance to Hirudotherapy

Alexander Kurdyumov is the contemporary Russian biochemist who turned Baskova's 1986 destabilase discovery into a translatable drug candidate. The path from Baskova's original characterization to a clinically-useful biological required four critical steps: heterologous expression of active enzyme in a scalable host (achieved by Kurdyumov in 2018), crystallographic determination of the active-site architecture (achieved with Baskova and colleagues in 2019, PDB entry 6OJ9), demonstration of in vivo efficacy in a model of clinical relevance (achieved with the 2021 PLOS ONE paper), and now (ongoing) IND-enabling toxicology in collaboration with Pharmstandard. The 2021 PLOS ONE paper was the breakthrough that brought destabilase to international attention. Kurdyumov's group used a murine inferior vena cava ligation model to produce experimentally-controlled venous thrombi, then allowed those thrombi to age for 7 days — long enough for Factor XIII-mediated isopeptide cross-linking to dominate the fibrin meshwork, rendering the clots resistant to plasmin and tPA-mediated fibrinolysis. Administered intravenously at this aged-clot timepoint, recombinant destabilase achieved 78% reduction in thrombus mass at 48 hours versus tPA's 22% reduction at the same timepoint. The mechanistic basis was equally well-characterized: destabilase cleaved precisely the γ-Glu-Lys isopeptide bonds that Factor XIII had introduced, restoring the thrombus to a plasmin-accessible state before further proteolytic degradation. The clinical implications are substantial. Chronic deep vein thrombosis — DVT that persists beyond 4-8 weeks despite anticoagulation — is currently managed with mechanical thrombectomy, catheter-directed thrombolysis (with high bleeding risk), or simply tolerated as chronic post-thrombotic syndrome. A specific biological that selectively dissolves aged clots while leaving fresh clots and intact vascular endothelium untouched would be a new therapeutic class. Kurdyumov's IND-enabling work with Pharmstandard is ongoing; first-in-human Phase I in chronic DVT patients is targeted for 2027. ASH considers him the most important contemporary translational biochemist in hirudotherapy.