A first-in-human study of the anti-inflammatory profibrinolytic TMS-007, an SMTP family triprenyl phenol.

AIMS: TMS-007, an SMTP family member, modulates plasminogen conformation and enhances plasminogen-fibrin binding, leading to promotion of endogenous fibrinolysis. Its anti-inflammatory action, mediated by soluble epoxide hydrolase inhibition, may contribute to its efficacy. Evidence suggests that TMS-007 can effectively treat experimental thrombotic and embolic strokes with a wide time window, while reducing haemorrhagic transformation. We aim to evaluate the safety, pharmacokinetics and pharmacodynamics of TMS-007 in healthy volunteers. METHODS: This was a randomized, placebo-controlled, double blind, dose-escalation study, administered as a single intravenous infusion of TMS-007 in cohorts of healthy male Japanese subjects. Six cohorts were planned, but only five were completed. In each cohort (n = 8), individuals were randomized to receive one of five doses of TMS-007 (3, 15, 60, 180 or 360 mg; n = 6) or placebo (n = 2). RESULTS: TMS-007 was generally well tolerated, and no serious adverse events were attributed to the drug. A linear dose-dependency was observed for plasma TMS-007 levels. No symptoms of bleeding were observed on brain MRI analysis, and no bleeding-related responses were found on laboratory testing. The plasma levels of the coagulation factor fibrinogen and the anti-fibrinolysis factor α2 -antiplasmin levels were unchanged after TMS-007 dosing. A slight increase in the plasma level of plasmin-α2 -antiplasmin complex, an index of plasmin formation, was observed in the TMS-007 group in cohort 2. CONCLUSIONS: TMS-007 is generally well tolerated and exhibits favourable pharmacokinetic profiles that warrant further clinical development.

Transcriptomic analysis of profibrinolytic and fibrinolytic inhibitor genes in COVID-19 patients.

The immunopathogenesis of COVID-19 infection is initiated by the entry of the SARS-CoV-2 virus into the human body through droplets, entering the lungs and binding to the ACE-2 receptor. Activated macrophages stimulate an immune and inflammatory response, leading to the activation of the coagulation cascade, including profibrinolytic and fibrinolytic inhibitor processes. One of the proteins involved in profibrinolytic is encoded by the PLAUR gene, while fibrinolytic inhibitor proteins are encoded by the A2M and SERPINE1 genes. This research aims to assess the transcriptomic analysis of genetic expression data of profibrinolytic genes, fibrinolytic inhibitor genes and their correlation with serum D-dimer levels, which describe the clinical condition of coagulation in COVID-19 patients. This cross-sectional study included 25 patients each for mild and moderate-to-severe COVID-19 at Dr. M. Djamil Padang General Hospital, Padang, Indonesia. Inter-group gene expression comparisons will be analyzed using log2 folds change, and bivariate tests will be analyzed using correlation. The results show that the PLAUR gene has higher expression in moderate-to-severe compared to mild cases. Similarly, the SERPINE1 and A2M genes expressions are higher in moderate-to-severe compared to mild cases. Furthermore, there is a significant correlation between serum D-dimer levels and profibrinolytic factor (PLAUR gene) expression in COVID-19 patients. The correlation between serum D-dimer levels with fibrinolytic inhibitor factor (SERPINE1 and A2M genes) expression was found. These conclude that there is a significant difference in the expression of the profibrinolytic and fibrinolytic inhibitor genes between mild and moderate-to-severe cases in COVID-19, demonstrating COVID-19 infection affects coagulation activities.

In vitro and in vivo characterisation of the profibrinolytic effect of an inhibitory anti-rat TAFI nanobody.

One of the main disadvantages of current t-PA thrombolytic treatment is the increased bleeding risk. Upon activation, thrombin activatable fibrinolysis inhibitor (TAFI) is a very powerful antifibrinolytic enzyme. Therefore, co-administration of a TAFI inhibitor during thrombolysis could reduce the required t-PA dose without compromising the thrombolytic efficacy. In this study we generated and characterised a nanobody that is inhibitory towards rat TAFI and evaluated its profibrinolytic property in vitro and in vivo. Nanobody VHH-rTAFI-i81 inhibits (at a 16-fold molar ratio nanobody over TAFI) the thrombin/thrombomodulin (T/TM)-mediated activation of rat TAFI (rTAFI) by 83 ± 1.8% with an IC50 of 0.46 (molar ratio nanobody over TAFI). The affinity (KA) of VHH-rTAFI-i81 for rTAFI, as determined by surface plasmon resonance (Biacore®), is 2.5 ± 0.2 x 10(10) M(-1) and illustrates a very strong binding. In an in vitro clot lysis assay, administration of VHH-rTAFI-i81 strongly enhances the degree of lysis and reduces time to reach full lysis of t-PA-mediated clot lysis. Epitope mapping discloses that Lys392 is of primary importance for the nanobody/rTAFI interaction besides minor contributions of Tyr175 and Glu183. In vivo application of VHH-rTAFI-i81 in a tissue factor-induced mouse thromboembolism model significantly decreases fibrin deposition in the lungs in the absence of exogenous administered t-PA. Nanobody VHH-rTAFI-i81 is a very potent inhibitor of T/TM-mediated TAFI activation. Co-administration of this nanobody and t-PA enhances the fibrinolytic efficacy. In an in vivo mouse thromboembolism model, VHH-rTAFI-i81 reduces fibrin deposition in the lungs.