Our testing shows multiple MOAs and efficacy against the major influenza and other viruses. We believe that clinical trials will support use as a front line therapy and prophylaxis against endemic and novel respiratory viruses, including emerging threats of pandemic potential and bioweapons. We are discussing further development with the U.S. military and other government agencies.
We are developing a nasal spray that can be taken at first symptoms of any respiratory viral infection without requiring a diagnosis – with the potential to avoid severe cases and limiting transmission. It can also be used prophylactically by those who can’t or won’t take vaccines or who want or need added protection (no vaccine is 100% effective, especially the seasonal flu vaccines). Prophylactic use could be episodic (before getting on a plane, going to a ball game, going to a restaurant, etc.) or for continuous periods (e.g., by health care workers, other front-line workers, military living in close quarters, staff and residents in senior living centers, etc.).
Florescence-based activity assays show that TA (in a concentration only 1/4 the concentration proposed for the nasal spray) completely inhibited the activity of TMPRSS2 and human airway trypsin-like protease (HAT aka TMPRSS11D), which are essential for the replication of many of the respiratory viruses, including SARS-CoV-2. In addition, TA partly inhibited multiple other proteases, and inhibited the ACE2-spike protein connection by at least 60% in a Surface Plasmon Resonance (SPR) assay.
Additionally, our testing in the cancer field shows that TA occupies the cationic amino acid transporters (CATs) that are required to transport lysine, arginine and histidine into cells (because of their positive charge), thereby inhibiting the protein proliferation required for cancer growth. We believe this mechanism is also relevant for the protein proliferation involved in viral replication. Indeed, arginine deprivation in particular has been identified as a targeted therapy for SARS-CoV-2, although the agents envisioned reduce systemic arginine rather than simply depriving it from infected cells as would be the case with TXCA’s.
TA’s proven secondary effects are also relevant for its use against respiratory viruses:
- inhibition of plasmin formation (reduces virulence, inflammation, additional cleavage of the spike protein) while preserving plasminogen availability.
- anti-inflammation
- modulation of the innate immune system
- stimulation of mitochondrial function
- protection of the endothelium
- enhancement of the effect of antibiotics
A safe influenza drug that acts against host proteins rather than viral proteins, and thus avoids the ability of the virus to mutate and become resistant, has been sought for over two decades. We believe that the TA nasal spray will provide a significant benefit to global health by reducing the loss of lives and livelihoods, hospitalizations, other healthcare costs, and the risk of future pandemics.
Extensive method and composition patent filings covering synthetic analogs, derivatives, and mimetics, and the new nasal spray mode of administration provide protectability.
Conducting clinical challenge studies against the primary respiratory viruses followed by reasonably sized population studies will be a highly efficient way to handle the required clinical studies. Expedited handling by the FDA should be available.