A febrile reaction is associated with high IgG antibody titers after the second and third BNT162b2 vaccination in Japan.

Adverse events are potentially associated with an IgG response after the BNT162b2 vaccination for severe acute respiratory syndrome coronavirus 2. In this study, we investigated the side effects of BNT162b2 vaccination using a health questionnaire and examined its relationship with IgG antibody titers. Serum samples were collected from participants 3 months after the second vaccination, just before the third vaccination, and 1 and 3 months after the third vaccination. A total of 505 participants who received three doses of vaccination were eligible for analysis. The results showed that post-vaccination body temperature correlated with anti-spike-receptor-binding domain (anti-S-RBD) antibody titers analyzed 3 months after the second (r = 0.30, p < 0.001) and third (r = 0.14, p < 0.001) vaccinations. Multivariate linear regression analysis revealed that age and severe swelling were negatively associated with log-transformed anti-S-RBD antibody levels, whereas sex (female), body temperature, and heat sensation were positively associated after the second vaccination. After the third vaccination, body temperature, and fatigue were positively associated with log-transformed anti-S-RBD antibody levels, and sex (female) was negatively associated. These results indicate that post-vaccination fever may be a marker of increased antibody titer.

Multidrug treatment for COVID-19.

An outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which began in Wuhan, China in December 2019, has rapidly spread all over the world. The World Health Organization characterized the disease caused by SARS-CoV-2 (COVID-19) as a pandemic in March 2020. In the absence of specific treatments for the virus, treatment options are being examined. Drug repurposing is a process of identifying new therapeutic uses for approved drugs. It is an effective strategy to discover drug molecules with new therapeutic indications. This strategy is time-saving, low-cost, and has a minimal risk of failure. Several existing approved drugs such as chloroquine, hydroxychloroquine, doxycycline, azithromycin, and ivermectin are currently in use because of their efficacy in inhibiting COVID-19. Multidrug therapy, such as a combination of hydroxychloroquine and azithromycin, a combination of doxycycline and ivermectin, or a combination of ivermectin, doxycycline, and azithromycin, has been successfully administered. Multidrug therapy is efficacious because the mechanisms of action of these drugs differ. Moreover, multidrug therapy may prevent the emergence of drug-resistant SARS-CoV-2.

Tetracycline plus macrolide: A potential therapeutic regimen for COVID-19?

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that struck in late 2019 and early 2020 is a serious threat to human health. Since there are no approved drugs that satisfactorily treat this condition, all efforts at drug design and/or clinical trials are warranted and reasonable. Drug repurposing is a well-known strategy that seeks to deploy existing licensed drugs for newer indications and that provides the quickest possible transition from the bench to the bedside to meet therapeutic needs. At present, several existing licensed drugs such as chloroquine, hydroxychloroquine, methylprednisolone, dexamethasone, and remdesivir have been used because of their potential efficacy in inhibiting COVID-19. Recently, antibiotics such as tetracyclines and macrolides have been reported to be effective against COVID-19. A combination of tetracyclines and macrolides may be a potential treatment for COVID-19 because there are some differences in the mechanism of action of tetracyclines and macrolides.

Macrolide treatment for COVID-19: Will this be the way forward?

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that has developed in late 2019 and 2020 is a serious threat to human health. With no vaccines or drugs approved for prevention and treatment until now, all efforts at drug design and/or clinical trials of already approved drugs are worthy and creditable. Using structure-based drug selection for identification of SARS-CoV-2 protease inhibitors, old drugs such as macrolides (MAC) were predicted to be effective for COVID-19. Lately, the anti-viral effects of macrolides have attracted considerable attention. Very recently, hydroxychloroquine in combination with azithromycin treatment was reported to be effective for COVID-19. We believe that treatments with macrolides alone or in combination with other drugs are promising and open the possibility of an international strategy to fight this emerging viral infection.