Olgotrelvir, a dual inhibitor of SARS-CoV-2 Mpro and cathepsin L, as a standalone antiviral oral intervention candidate for COVID-19.

BACKGROUND: Oral antiviral drugs with improved antiviral potency and safety are needed to address current challenges in clinical practice for treatment of COVID-19, including the risks of rebound, drug-drug interactions, and emerging resistance. METHODS: Olgotrelvir (STI-1558) is designed as a next-generation antiviral targeting the SARS-CoV-2 main protease (Mpro), an essential enzyme for SARS-CoV-2 replication, and human cathepsin L (CTSL), a key enzyme for SARS-CoV-2 entry into host cells. FINDINGS: Olgotrelvir is a highly bioavailable oral prodrug that is converted in plasma to its active form, AC1115. The dual mechanism of action of olgotrelvir and AC1115 was confirmed by enzyme activity inhibition assays and co-crystal structures of AC1115 with SARS-CoV-2 Mpro and human CTSL. AC1115 displayed antiviral activity by inhibiting replication of all tested SARS-CoV-2 variants in cell culture systems. Olgotrelvir also inhibited viral entry into cells using SARS-CoV-2 Spike-mediated pseudotypes by inhibition of host CTSL. In the K18-hACE2 transgenic mouse model of SARS-CoV-2-mediated disease, olgotrelvir significantly reduced the virus load in the lungs, prevented body weight loss, and reduced cytokine release and lung pathologies. Olgotrelvir demonstrated potent activity against the nirmatrelvir-resistant Mpro E166 mutants. Olgotrelvir showed enhanced oral bioavailability in animal models and in humans with significant plasma exposure without ritonavir. In phase I studies (ClinicalTrials.gov: NCT05364840 and NCT05523739), olgotrelvir demonstrated a favorable safety profile and antiviral activity. CONCLUSIONS: Olgotrelvir is an oral inhibitor targeting Mpro and CTSL with high antiviral activity and plasma exposure and is a standalone treatment candidate for COVID-19. FUNDING: Funded by Sorrento Therapeutics.

[Impacts of electroacupuncture on left hippocampus NAA/Cr for patients of Uygur and Han nationality with mild cognitive impairment].

OBJECTIVE: To observe the clinical efficacy of electroacupuncture (EA) on mild cognitive impairment (MCI) for patients of Uygur and Han nationality and explore the national diversity among the patients with MCI. METHODS: Twenty-five cases were divided into Han nationality group (15 cases) and Uygur nationality group (10 cases) according to patient's nationality. In either group, EA was applied to Baihui (GV 20), Fengchi (GB 20), Xuanzhong (GB 39), Fuliu (KI 7), Sanyinjiao (SP 6) and Taixi (KI 3), once per day, 15 treatments made one session and there were 5 days at the interval among the sessions. Totally, 3 sessions of treatment were required. The proton magnetic resonance spectroscopy (1H-MRS) was used to observe the changes in the ratio of N-acetylaspartate and creatine (NAA/Cr) on the left hippocampus for the patients in two groups before and after treatment as well as the changes in the results of the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) separately. RESULTS: NAA/Cr in Uygur nationality group was higher than that in Han nationality group before treatment (1.659 +/- 0.418 vs 1.137 +/- 0.190, P < 0.05). After treatment, MMSE and MoCA scores all increased apparently as compared with those before treatment in two groups (P < 0.05, P < 0.01), and NAA/Cr on the left hippocampus in either group was up-regulated as compared with that before treatment (both P < 0.01). CONCLUSION: EA can improve the overall cognitive function for the patients with MCI. There is the national diversity in the partial brain metabolite level between Uygur patients and Han patients with MCI.

[Experimental study on effect of pre-acupuncture and moxibustion on molecular markers in pre-thrombosis state of rats].

OBJECTIVE: To explore the best method for prevention and treatment of thrombosis and its mechanism. METHODS: Forty SD rats were randomly divided into a blank group, a model group, an electroacupuncture group and a crude herb moxibustion group. In the electroacupuncture group and the crude herb moxibustion group. "Zusanli" (ST 36), "Sanyinjiao" (SP 6), "Pishu" (BL 20) and "Geshu" (BL 17) were punctured or moxibusted for 2 weeks, then pre-thrombosis model was induced by Adrenalin Hydrochloride and ice water method in the model group, the electroacupuncture group and the crude herb moxibustion group, respectively. Molecular markers in venous blood after the model made in 18 hours were detected. RESULTS: Act: vaty of tissue-type plasminogen activator (t-PA) and content of alpha-granule membrane protein (GMP-140) decreased and content of nitrogen monoxidum (NO) increased after electroacupuncture or crude herb moxibustion. The levels of t-PA and GMP-140 in the model group were higher than those in the electroacupuncture group, the crude herb moxibustion group and the blank group (all P < 0.05), and the content of NO in the model group was lower than those in the electroacupuncture group, the crude herb moxibustion group and the blank group (all P < 0.05), while there was no significant difference in t- PA, GMP-140 and NO among the crude herb moxibustion group, electroacupuncture group and blank group (all P > 0.05). CONCLUSION: Electroacupuncture and crude herb moxibustion can significantly change the contents of t-PA, GMP-140 and NO and there was no significant difference between the two therapies.

Stability studies of anticancer agent bis(4-fluorobenzyl)trisulfide and synthesis of related substances.

Bis(4-fluorobenzyl)trisulfide, fluorapacin, has been extensively developed as a promising new anticancer drug candidate. Its degradation products were identified and verified by the newly synthesized compounds bis(4-fluorobenzyl)disulfide (A) and bis(4-fluorobenzyl)tetrasulfide (B) which were resulted from the disproportionation of fluorapacin under forced conditions. A stability-indicating HPLC method was used for the stability evaluation of active pharmaceutical ingredient (API) fluorapacin and finished pharmaceutical product (FPP) under various conditions. High recovery (99.57%) of API was found after three freeze-thaw cycle processes of fluorapacin FPP. Susceptibility of fluorapacin to oxidative degradation was studied by treating fluorapacin and FPP in 30% hydrogen peroxide aqueous solution, and the result verified the oxidative stability of fluorapacin. However, treatment of this drug candidate under strong light (4500 Lx+/-500 Lx) for 10 days showed substantial effect on the recovery of fluorapacin, especially from fluorapacin FPP. Strong acid (1.0M, HCl) did not affect the recovery of fluorapacin while strong basic condition (1.0M, NaOH) accelerated the disproportionation of fluorapacin to its related substances A and B. The stability of fluorapacin in its aqueous media at a pH range of 2.0-10.0 for up to 6h was further investigated, and 4.0-8.0 was found to be the most stable pH range. Fluorapacin and FPP were exposed to the elevated temperatures of 40 and 60 degrees C for 10 days without obvious impact on their stability. The thermal stability of fluorapacin API and FPP under constant humidity with light protection was also thoroughly investigated under accelerated (40+/-2 degrees C, RH 75+/-5%, 6 months) and long-term (25+/-2 degrees C, RH 60+/-10%, 24 months) conditions. There was no significant change except minor color change of fluorapacin FPP. Therefore, fluorapacin has excellent stability as a potential drug candidate for further clinical development investigation.

Quantitative determination of anti-tumor agent bis(4-fluorobenzyl)trisulfide, fluorapacin and its pharmaceutical preparation by high-performance liquid chromatography.

A simple isocratic and stability-indicating HPLC method was developed and validated for the quantitative determination of anti-tumor agent fluorapacin and its pharmaceutical preparation. A Spherisorb ODS II C(18) (250 mm x 4.6 mm, 5 microm) column was eluted with a mobile phase consisting of acetonitrile/water (85:15, v/v). The analyses were performed at 40+/-1 degrees C with a flow rate of 1.0 mL/min and UV detection at 218 nm. The calibration curve was linear over a concentration range of 160-240 microg/mL with the correlation coefficient of 0.9997. The LOD and LOQ were determined to be 1.4 and 7.0 ng/mL, respectively. Average recoveries were 98.27% and 100.40% for fluorapacin API and its drug product with corresponding relative standard deviations (R.S.D.) of 0.41% and 0.30%, respectively. Good repeatability (precision and intermediate precision), accuracy and tolerability were obtained with R.S.D. of <1.0%. This specific and reliable method has been successfully applied for quality control of fluorapacin API and drug product.