| Id |
Subject |
Object |
Predicate |
Lexical cue |
| T256 |
0-90 |
Sentence |
denotes |
To conclude, the HCQ treatment of SARS-CoV-2 infection was not met with its hoped success. |
| T257 |
91-248 |
Sentence |
denotes |
This is probably related to the inability of the dosing regimens currently in use to achieve the blood concentration required for the HCQ antiviral activity. |
| T258 |
249-487 |
Sentence |
denotes |
Initially, based on physiological pharmacokinetic models, Yao et al. recommended for SARS-CoV-2 infection a loading oral HCQ dose of 400 mg twice daily, followed by a maintenance dose of 200 mg administered twice daily for four days [50]. |
| T259 |
488-825 |
Sentence |
denotes |
However, this recommended HCQ dosage regimen was based only on the ratio of free lung trough concentration to in vitro EC50 values (the EC50 of HCQ for SARS-CoV-2 ranged between 0.72 and 17.31µM) and did not consider the tendency of HCQ to accumulate within acidic cellular organelles like endosomes, lysosomes, and Golgi apparatus [69]. |
| T260 |
826-981 |
Sentence |
denotes |
In fact, it has been demonstrated that HCQ concentration in lysosomes is higher than the extracellular concentration (80 µM vs. 0.5 µM, respectively) [70]. |
| T261 |
982-1145 |
Sentence |
denotes |
Based on these results, it was considered necessary to compare the EC50 values obtained in vitro with the plasma concentration and not with the lung concentration. |
| T262 |
1146-1434 |
Sentence |
denotes |
In a study investigating HCQ pharmacokinetics in COVID-19 patients treated with 600 mg/day of HCQ, it was found that the mean blood concentration of HCQ was 0.46 mg/day [32], which was below the lowest estimated levels of 0.48 mg/mL corresponding to the in vitro concentration of 0.72 µM. |
| T263 |
1435-1642 |
Sentence |
denotes |
Further, a plasma concentration predicted for HCQ antiviral EC50 made by Garcia-Cremades et al. found that it should be 4,7 µM corresponding to 1.58 mg/mL, which is much higher than in vivo plasmatic values. |
| T264 |
1643-1833 |
Sentence |
denotes |
To reach this plasma concentration, it should be necessary to take an amount of HCQ higher than 400 mg twice a day for five days or more [71], which would increase the onset of side effects. |
| T265 |
1834-2087 |
Sentence |
denotes |
Thus, the ineffectiveness of HCQ antiviral activity again SARS-CoV-2 can be related to the low current dosing regimens and the impossibility to increase the administered doses due to the increased risk of severe side effects, especially QT prolongation. |