Sairiyo Therapeutics Inc.
Sairiyo Therapeutics Inc. is a biotechnology company focused on the development of its patented enteric-coated oral Cepharanthine (“PD-001”) for viral infectious diseases. PharmaTher owns 49% of Sairiyo Therapeutics and plans to crystallize value through various avenues, including the sale of all or part of its interest, a spin-out, or another public company transaction.
About PD-001 (Enteric-coated Oral Cepharanthine)
Cepharanthine is a natural product and an approved drug used for more than 70 years in Japan to successfully treat a variety of acute and chronic diseases. In clinical research, cepharanthine has been shown to exhibit multiple pharmacological properties including anti-oxidative, anti-inflammatory, immuno-regulatory, anti-cancer, anti-viral and anti-parasitic effects. However, historically cepharanthine's low oral bioavailability has represented a major obstacle to realizing its full clinical potential.
Compared to generic cepharanthine, PD-001 has been shown in rodent and non-rodent models to possess markedly improved oral bioavailability (more easily absorbed). These findings support the development of an orally administered formulation, and in so doing, removes the undesirable requirement for frequent intravenous dosing to maintain therapeutic levels of drug in circulation. Sairiyo endeavours to develop an efficacious oral therapeutic to potentially improve outcomes for infectious disease and oncology applications.
PD-001 is protected by US Patent US10576077, with a patent expiration date of March 23, 2036.
Cepharanthine is a natural product and an approved drug used for more than 70 years in Japan to successfully treat a variety of acute and chronic diseases. In clinical research, cepharanthine has been shown to exhibit multiple pharmacological properties including anti-oxidative, anti-inflammatory, immuno-regulatory, anti-cancer, anti-viral and anti-parasitic effects. However, historically cepharanthine's low oral bioavailability has represented a major obstacle to realizing its full clinical potential.
Compared to generic cepharanthine, PD-001 has been shown in rodent and non-rodent models to possess markedly improved oral bioavailability (more easily absorbed). These findings support the development of an orally administered formulation, and in so doing, removes the undesirable requirement for frequent intravenous dosing to maintain therapeutic levels of drug in circulation. Sairiyo endeavours to develop an efficacious oral therapeutic to potentially improve outcomes for infectious disease and oncology applications.
PD-001 is protected by US Patent US10576077, with a patent expiration date of March 23, 2036.
Infectious Diseases Opportunity
Independent published research has identified cepharanthine as a potential Hantavirus entry inhibitor. In the study titled Screening and identification of HTNVpv entry inhibitors with high-throughput pseudovirus-based chemiluminescence, researchers developed a high-throughput screening method using Hantaan virus pseudovirus (“HTNVpv”) and evaluated a library of 1,813 approved drugs and 556 small-molecule compounds. The study identified six compounds with anti-HTNVpv activity in the low-micromolar range, including cepharanthine. Among the selected compounds, cepharanthine not only demonstrated in vitro anti-HTNVpv activity but also inhibited HTNVpv-fluc infection in Balb/c mice. In that mouse model, cepharanthine inhibited Hantavirus pseudovirus infection 5 hours after infection by approximately 94% at 180 mg/kg/day, 93% at 90 mg/kg/day, and 92% at 45 mg/kg/day, with statistical significance reported at P < 0.01. The researchers also reported that time-of-addition analysis suggested cepharanthine may act during the viral entry and membrane fusion phases, which are important early steps in the hantavirus infection cycle. The authors concluded that cepharanthine may represent a candidate for further evaluation in hantavirus-related diseases, including HFRS and hantavirus cardiopulmonary syndrome.
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