A randomized trial to assess the acceleration of viral clearance by the combination Favipiravir/Ivermectin/Niclosamide in mild-to-moderate COVID-19 adult patients (FINCOV)

BACKGROUND

The efficacy of the viral clearance and clinical outcomes of favipiravir (FPV) in outpatients being treated for coronavirus disease 2019 (COVID-19) is unclear. Ivermectin (IVM), niclosamide (NCL), and FPV demonstrated synergistic effects in vitro for exceed 78% inhibiting severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) replication.

METHODS

A phase 2, open-label, 1:1, randomized, controlled trial was conducted on Thai patients with mild-to-moderate COVID-19 who received either combination FPV/IVM/NCL therapy or FPV alone to assess the rate of viral clearance among individuals with mild-to-moderate COVID-19.

RESULTS

Sixty non-high-risk comorbid patients with mild-to-moderate COVID-19 were randomized; 30 received FPV/IVM/NCL, and 30 received FPV alone. Mixed-effects multiple linear regression analysis of the cycle threshold value from SARS-CoV-2 PCR demonstrated no statistically significant differences in viral clearance rates between the combined FPV/IVM/NCL therapy group and the FPV-alone group. World Health Organization Clinical Progression scores and symptomatic improvement did not differ between arms on days 3, 6, and 10, and no adverse events were reported. No patients required hospitalization, intensive care unit admission, or supplemental oxygen or died within 28 days. C-reactive protein on day 3 was lower in the FPV/IVM/NCL group.

CONCLUSION

Viral clearance rates did not differ significantly between the FPV/IVM/NCL combination therapy and FPV-alone groups of individuals with mild-to-moderate COVID-19, although the combined regimen demonstrated a synergistic effect in vitro. No discernible clinical benefit was observed. Further research is required to explore the potential benefits of FVP beyond its antiviral effects.

TRIAL REGISTRATION

TCTR20230403007, Registered 3 April 2023 - Retrospectively registered,https://trialsearch.who.int/Trial2.aspx?TrialID=TCTR20230403007.

Efficacy of combined COVID-19 convalescent plasma with oral RNA-dependent RNA polymerase inhibitor treatment versus neutralizing monoclonal antibody therapy in COVID-19 outpatients: a multi-center, non-inferiority, open-label randomized controlled trial (PlasMab)

IMPORTANCE

This pivotal study reveals that high neutralizing titer COVID-19 convalescent plasma therapy (CPT) combined with favipiravir (FPV) is non-inferior to sotrovimab in preventing hospitalization and severe outcomes in outpatients with mild-to-moderate COVID-19 and high-risk comorbidities. It underscores the potential of CPT-FPV as a viable alternative to neutralizing monoclonal antibodies like sotrovimab, especially amid emerging variants with spike protein mutations. The study's unique approach, comparing a monoclonal antibody with CPT, demonstrates the efficacy of early intervention using high neutralizing antibody titer CPT, even in populations with a significant proportion of elderly patients. These findings are crucial, considering the alternative treatment challenges, especially in resource-limited countries, posed by the rapidly mutating SARS-CoV-2 virus and the need for adaptable therapeutic strategies.

The real-world effectiveness of fluvoxamine therapy in mild to moderate COVID-19 patients; A historical cohort study (Fluvoxa Trial)

BACKGROUND

Fluvoxamine (FVX) has been proposed as a potential treatment for severe COVID-19 by the σ-1 receptor agonist, which can reduce cytokine production. However, the efficacy of FVX remains controversial.

METHODS

A historical retrospective cohort study was conducted in mild to moderate COVID-19 patients, 2:1 ratio of standard of care (SOC) and FVX treatments to assess the effectiveness of FVX in preventing deterioration by the fifth day of treatment.

RESULTS

Of 752 eligible patients, 234 received FVX while 518 received SOC, and there was no significant difference in the effectiveness of FVX and SOC in preventing clinical deterioration. On the fifth day after treatment, 86.1 % of patients in the FVX-treated group did not experience clinical deterioration compared to 78.7 % in the SOC group. Notably, the FVX group had higher rates of pneumonia development and hospitalization, requiring more oxygen supplementation while showing less reduction in viral shedding than the SOC group. However, no difference in mechanical ventilation use, ICU admission, and survival was observed.

CONCLUSION

Fluvoxamine treatment is failed to demonstrate effectiveness in preventing deterioration in mild to moderate COVID-19 and may lead to a higher incidence of pneumonia, hospitalization, and oxygen supplementation, necessitating careful consideration before prescribing the drug for COVID-19.

Efficacy of Andrographis paniculata extract treatment in mild to moderate COVID-19 patients being treated with favipiravir: A double-blind, randomized, placebo-controlled study (APFaVi trial)

BACKGROUND

While favipiravir had been the standard anti-SARS-CoV-3 drug for COVID-19 treatment in Thailand, the efficacy of favipiravir treatment is controversial. Andrographis paniculata extract (APE) inhibits viral entry, exhibits immunomodulatory effects, and proposes to have the potential for early-stage COVID-19 treatment.

METHODS

A randomized, double-blind, placebo-controlled trial was performed in Thailand during June - September 2021. Non-severe COVID-19 patients were randomized 1:1 to groups receiving 180 mg/day of APE plus favipiravir (APE-FPV group) or placebo plus favipiravir (placebo-FPV group). Efficacy in preventing disease progression to severe COVID-19 was assessed on day 4, using World Health Organization Clinical Progression Scale (WHOCPS) score and visual analog scale (VAS) for acute respiratory tract infection symptoms.

RESULTS

Of 146 patients, there were 73 patients in each group. Non-deterioration of WHOCPS scores on day 4 was 98.63% versus 97.26% of patients in the APE-FPV and placebo-FPV groups (p = 1.000). No difference in supplemental oxygen, hospitalization, and death was shown in both groups. The oxygen supplemental was 4.11% in the placebo-FPV group. The interleukin (IL)-1β was significantly lower in the APE than in the placebo-FPV group throughout the study. We found no difference in virologic outcomes between groups and no substantial adverse events.

CONCLUSIONS

APE treatment did not demonstrate additional clinical and virological benefits in patients with mild to moderate COVID-19 being treated with favipiravir. Early reduction of IL-1β with APE may be advantageous in preventing cytokine storms in severe COVID-19 and requires further study.

Favipiravir treatment in non-severe COVID-19: promising results from multicenter propensity score-matched study (FAVICOV)

This study aimed to evaluate the efficacy of favipiravir (FPV) in preventing the development of severe COVID-19 in patients with mild-to-moderate symptoms. The study evaluated 1037 COVID-19 patients treated with FPV or standard treatment between April and September 2021, analyzed by propensity score matching. 149 patients were included in each arm after propensity score matching. The clinical outcomes showed no deterioration of the WHO clinical progression scale in the FPV group compared to the standard treatment group on day 5 (83.2% vs. 69.1%, p < 0.001). The WHO clinical progression scale also showed improvements on day 14 in the FPV group compared to the standard treatment group (66.4% vs. 46.3%, p < 0.001). The rates of oxygen supplementation and hospitalization were significantly lower in the FPV group compared to the standard treatment group (0% vs. 12.1% and 0.7% vs. 17.4%, respectively, p < 0.001 for both). There were no differences in adverse events between the two groups. The study highlights the effectiveness of FPV in preventing severe COVID-19 and hospitalization in patients with mild-to-moderate symptoms. The findings emphasize the importance of personalized treatment plans for COVID-19 patients, starting FPV treatment early, and adjusting dosages based on ethnicity and body weight.

Efficacy of combination therapy of fluvoxamine and favipiravir vs favipiravir monotherapy to prevent severe COVID-19 among mild to moderate COVID-19 patients: Open-label randomized controlled trial (EFFaCo study)

OBJECTIVES

Fluvoxamine (FVX) is an antidepressant proposed to its immunomodulatory effects in preventing deterioration in mild and moderate COVID-19.

METHODS

An open-label, 1:1 randomized controlled trial was assigned either combination therapy 50 mg twice daily of FVX for 10 days and favipiravir (FPV) or FPV alone to assess the efficacy in preventing disease progression in mild to moderate COVID-19 on the 5th day.

RESULTS

In total, 134 patients with mild COVID-19 received FPV and 132 received FVX/FPV, 31 patients with moderate COVID-19 received FPV/dexamethasone (FPV/Dex), and 30 received FVX/FPV/Dex. The intention-to-treat (ITT) analysis showed no difference of no clinical deterioration on the 5th day in both mild COVID-19 (100% in FPV vs 97% in FVX/FPV) and moderate COVID-19 (83.9% in FPV/Dex vs 86.7% in FVX/FPV/Dex). However, there was a low rate of oxygen supplemental, hospitalization, or intensive care in both groups and zero death in all groups. No significant difference in oxygen supplemental, hospitalization, radiological, virological, or biochemical outcomes, and the immunomodulatory effect was observed between the group.

CONCLUSION

The combined fluvoxamine treatment did not add benefit in preventing deterioration in patients with mild to moderate COVID-19 without the immunomodulatory effect observed, although it demonstrated low hospitalization rates, oxygen supplemental, intensive care needed, and zero mortality.

TRIAL REGISTRATION

Thai clinical trials registry (TCTR) no. 20210615002.

The immunogenicity of the ChAdOx1 nCoV-19 vaccination in participants with underlying comorbidity diseases: A prospective cohort study

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) increases mortality rates in older adults and those with comorbidities. Individuals with certain comorbidities may have a poor immune response and require early booster vaccines. We aimed to assess the immune response after two doses of ChAdOx1 nCoV-19 vaccine, at 84-day intervals, in participants with the following comorbidities; diabetes mellitus; obesity; cardiovascular disease; chronic kidney disease; rheumatological disease; cirrhosis; hematological disease; hematological malignancy; or solid malignancy. The study was conducted at Chulabhorn Hospital in Thailand, with healthy healthcare workers serving as the control group. Of the 769 participants, 352 were in the healthy cohort and 417 were in the comorbidity cohort, all received at least one dose of vaccine. Anti-RBD total antibody levels were evaluated on Day 0, Day 84, and Day 112. The results at Day 112 (4 weeks after the second dose) showed that individuals with comorbidities had a poor immune response compared to healthy individuals, especially those with hematological malignancy and solid malignancy. The geometric mean concentration (GMC) of anti-RBD antibody in the comorbidity cohort was significantly lower than that in the healthy cohort: 433.66 BAU/ml (95% CI 334.62-562.01) versus 1096.14 BAU/ml (95% CI 1010.26-1189.33), respectively. The geometric mean ratio (GMR) between the two cohorts was 0.40 (95% CI 0.30-0.52, p < .001). This study concluded that individuals with comorbidities, particularly hematological and solid malignancies, had poor immune responses and may require an early booster vaccine to prevent infection and death.

Dynamics of anti-RBD (anti-receptor binding domain) levels in diabetes patients following the ChAdOx1 nCoV-19 vaccine (AZD1222) in the Thai population

The ChAdOx1 nCoV-19 vaccine (AZD1222) was used in Thailand during the early outbreak of coronavirus disease 2019 (COVID-19). A previous study showed a low immune response in diabetes patients after the first dose of the AZD1222 vaccine. Furthermore, humoral immune responses after the second vaccination were inconsistent. This study evaluated the immunogenicity following the first and second doses of the AZD1222 vaccine in people with type 2 diabetes (T2D) compared with the general population of Thailand. This was a prospective, single-center cohort study. 59 adults with T2D and 118 age- and sex-matched healthcare personnel were eligible. The participants received two doses of AZD1222 12 weeks apart. Antibodies against the receptor-binding domain (anti-RBD) of the SARS-CoV-2 spike protein, using an automated electrochemiluminesence immunoassay (ECLIA), were measured at baseline, 8 and 12 weeks after the first dose of vaccine, and 4 weeks after the second dose of vaccine. The anti-RBD levels were reported as the geometric mean concentration (GMC) and compared between groups using the geometric mean ratio (GMR). A total of 177 participants were included: The average age of 59 T2D patients was 60.1 years (SD: 11.4), and 31 (52.5%) of them were female. The GMC of anti-RBD 8 and 12 weeks after the first vaccination were significantly lower in T2D (week 8 60; 17.05 BAU/mL, 95% confidence interval [CI]   11.1-26.19, P = 0.035, week 12; 24.68 BAU/mL, 95% CI  16.4-37.0, P = 0.002) than in those without diabetes (week 8; 29.79 BAU/mL, 95% CI  22.07-40.42, week 12; 50.67 BAU/mL, 95% CI  40.62-63.20). However, there was no difference in the GMC of anti-RBD 4 weeks after the second vaccination among groups (T2D; 687.95 BAU/mL, 95% CI  462.7-1022.7, Normal; 697.95 BAU/mL, 95% CI 583.7-834.5, P = 0.947). In both groups, the GMC of anti-RBD was persistently high without decline 12 weeks after the first vaccination. Albuminuria was a major factor related to low humoral immune responses in T2D patients after the second dose of AZD122 vaccine (the GMR was 0.29, 95% CI 0.08-0.98, P = 0.047) whereas the HbA1C level and age were not. Immunogenicity in T2D cases was lower than in the normal population after the first dose of the AZD1222 vaccine. The two doses of AZD122 vaccine induced immunity in T2D equal to that of normal individuals in Thailand. People with diabetes should be boosted as soon as possible to induce adequate immunity to prevent COVID-19 infection.

The Real-World Clinical Outcomes of Favipiravir Treatment with Telemedicine Monitoring in Preventing Disease Progression in Mild to Moderate COVID-19 Patients; A Retrospective Cohort Study

Background: Favipiravir has complex pharmacokinetics, and varied efficacy has been reported in treating COVID-19. Telehealth and telemonitoring are disruptive challenges used for COVID-19 care during pandemics. Objective: This study aimed to assess the outcome of favipiravir treatment to prevent clinical deterioration in mild to moderate COVID-19 cases with adjunctive telemonitoring during the COVID-19 surge. Methods: This was a retrospective observational study of PCR-confirmed mild to moderate COVID-19 cases subjected to home isolation. Chest computed tomography (CT) was performed in all cases, and favipiravir was administrated. Results: This study involved 88 PCR-confirmed COVID-19 cases. In addition, 42/42 (100%) cases were Alpha variants. COVID-19 pneumonia was found in 71.5% of the cases, according to chest X-rays and chest CT on the first visit. Favipiravir started 4 days after symptoms, which was part of the standard of care. The 12.5% of the patients required supplemental oxygen and intensive care unit admission rate was 1.1%; 1.1% required mechanical ventilation, and the rate of all-cause mortality was 1.1%, with a value of 0% of severe COVID-19 deaths. All mild illness cases showed no clinical deterioration or requirement for supplemental oxygen. No significant deterioration in either obesity or diabetes mellitus was observed. Conclusions: Favipiravir treatment for mild to moderate COVID-19 cases in outpatient settings, coupled with telemonitoring, was both safe and effective in preventing clinical deterioration, including the need for oxygen supplementation. This approach proved valuable during surges of COVID-19 cases.

Immunogenicity and reactogenicity of heterologous prime-boost vaccination with inactivated COVID-19 and ChAdOx1 nCoV-19 (AZD1222) vaccines, a quasi-experimental study

The global supply of COVID-19 vaccines has been limited, and concerns have arisen about vaccine supply chain disruptions in developing countries. Heterologous prime-boost vaccination, which involves using different vaccines for the first and second doses, has been proposed to enhance the immune response. We aimed to compare the immunogenicity and safety of a heterologous prime-boost vaccination using an inactivated COVID-19 vaccine and AZD1222 vaccine with that of a homologous vaccination using AZD1222. This pilot involved 164 healthy volunteers without prior SARS-CoV-2 infection aged 18 years or older assigned to receive either the heterologous or homologous vaccination. The results showed that the heterologous approach was safe and well-tolerated, although the reactogenicity of the heterologous approach was higher. At 4 weeks after receiving the booster dose, the heterologous approach elicited a non-inferior immune response compared to the homologous approach in neutralizing antibody and cell-mediated immune response. The percentage of inhibition was 83.88 (79.72-88.03) in the heterologous and 79.88 (75.50-84.25) in the homologous group, a mean difference of 4.60 (-1.67-10.88). The geometric mean of interferon-gamma was 1072.53 mIU/mL (799.29-1439.18) in the heterologous group and 867.67 mIU/mL (671.94-1120.40) in the homologous group, a GMR of 1.24 (0.82-1.85). However, the binding antibody test of the heterologous group was inferior to the homologous group. Our findings suggest that the use of heterologous prime-boost vaccination with different types of COVID-19 vaccines is a viable strategy, especially in settings where vaccine supply is limited or where vaccine distribution is challenging.

Immunogenicity of the ChAdOx1 nCoV-19 vaccine in patients with hematologic malignancies

Purpose

The present study aimed to study the immunogenicity of the ChAdOx1 nCoV-19 vaccine in patients with hematologic malignancies.

Materials and Methods

This prospective cohort study of hematology patients aimed to evaluate their antibody levels against the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and seroconversion rates following two doses of the ChAdOx1 nCoV-19 vaccine. Between June and July 2021, we enrolled 61 patients and included 44 patients in our analysis. Antibody levels were assessed 8 and 4 weeks after the first and second injections, respectively, and compared with those of a healthy group.

Results

Eight weeks after the first dose, the geometric mean antibody level was 1.02 binding antibody units (BAU)/mL in the patient group and 37.91 BAU/mL in the healthy volunteer group (p<0.01). Four weeks after the second dose, the geometric mean antibody level was 9.44 BAU/mL in patients and 641.6 BAU/mL in healthy volunteers (p<0.01). The seroconversion rates 8 weeks after the first dose were 27.27% and 98.86% in the patient and healthy volunteer groups, respectively (p<0.001). The seroconversion rate 4 weeks after the second dose was 47.73% in patients and 100% in healthy volunteers. Factors leading to lower seroconversion rates were rituximab therapy (p=0.002), steroid therapy (p<0.001), and ongoing chemotherapy (p=0.048). Factors that decreased antibody levels were hematologic cancer (p<0.001), ongoing chemotherapy (p=0.004), rituximab (p<0.001), steroid use (p<0.001), and absolute lymphocyte count <1,000/mm³ (p=0.009).

Conclusion

Immune responses were impaired in individuals with hematologic malignancies, particularly patients undergoing ongoing therapy and B-cell-depleting therapy. Additional vaccinations should be considered for these patients, and further investigated.

Immune Response to CoronaVac and Its Safety in Patients with Type 2 Diabetes Compared with Healthcare Workers

Background: Vaccines for SARS-CoV-2 have been critical for preventing disease. Previous research showed patients with diabetes have impaired immunity. This study aimed to determine the immunity to coronavirus after CoronaVac by comparing patients with type 2 diabetes (T2D) and healthcare workers (HCW). Materials and methods: A prospective cohort study evaluated immune responses and safety after two doses of CoronaVac in T2D and HCW groups at Chulabhorn Hospital. The levels of total antibodies against the receptor-binding domain (anti-RBD) of the SARS-CoV-2 spike protein at baseline and 4 weeks after vaccination were collected. The level of anti-RBD concentrations was reported as geometric mean concentration (GMC) and compared between groups using the geometric mean ratio (GMR). Results: 81 participants were included; 27 had T2D and 54 were HCW. After complete vaccination, anti-RBD concentrations were not significantly different between T2D (57.68 binding antibody units (BAU)/mL, 95% confidence interval (CI) = 29.08; 114.44) and HCW (72.49 BAU/mL, 95% CI = 55.77; 94.22) groups. Subgroup analysis showed the GMC of anti-RBD was significantly lower in T2D patients with dyslipidaemia (50.04 BAU/mL) than in T2D patients without dyslipidaemia (341.64 BAU/mL). Conclusions: The immune response at 4 weeks after two doses of CoronaVac did not significantly differ between patients with T2D and HCW.

Difference in Immunogenic Responses to COVID-19 Vaccines in Patients With Cancer Receiving Chemotherapy Versus Nonchemotherapy Treatment

PURPOSE

The COVID-19 pandemic has affected public health worldwide. The efficacy and safety of COVID-19 vaccines have been evaluated in the general population; however, data on patients with malignancies are limited.

METHODS

This prospective longitudinal observational cohort study was conducted between June and July 2021. Enrolled adult patients with cancer were divided into chemotherapy and nonchemotherapy groups. All participants were immunized with two doses of the ChAdOx1 nCoV-19 or CoronaVac COVID-19 vaccines. The primary outcome was a comparison of the immunogenicity (as assessed by spike protein [anti-S] immunoglobulin G [IgG] antibody titers) of two doses of COVID-19 vaccine in the chemotherapy and nonchemotherapy groups. The secondary outcomes included the anti-S IgG seroconversion rate and vaccine safety in both groups.

RESULTS

Among the 173 enrolled patients with solid cancer, after COVID-19 vaccination, the chemotherapy group had a significantly lower median anti-S IgG titer than the nonchemotherapy group (26 v 237 U/mL, P < .001). A statistically significant difference in anti-S IgG titer was found between groups vaccinated with CoronaVac (7 v 90 U/mL, P < .001), but no difference was found in those vaccinated with ChAdOx1 nCoV-19 (818 v 1061 U/mL, P = .075). The anti-S IgG seroconversion rate was significantly lower in the chemotherapy group than that in the nonchemotherapy group (78.9% v 96.5%, P = .001). No new or serious vaccine-related adverse events were reported.

CONCLUSION

Patients with solid cancer receiving a COVID-19 vaccine while undergoing chemotherapy had lower immunogenicity responses to vaccination than those who were vaccinated while undergoing nonchemotherapy treatment. No statistically significant difference was observed in the COVID-19 vaccine safety profiles between groups.

Persistence of immunogenicity, contributing factors of an immune response, and reactogenicities after a single dose of the ChAdOx1 (AZD1222) COVID-19 vaccine in the Thai population

INTRODUCTION

Due to the vaccine's short supply and the efficacy of a single dose of the ChAdOx1 (AZD1222) vaccine, many governments delayed the interval between prime and boost dose from 4 to 8-12 weeks. However, the waning of immune response in this period is a concern. This study evaluated the durability, contributing factors of anti-RBD antibody concentration, and reactogenicities after the single dose of AZD1222 vaccine in the Thai population.

METHODS

This was a single-center, prospective cohort study at Chulabhorn Hospital, Bangkok, Thailand. Individuals 18 years or older who were negative for anti-SARS-CoV-2 antibody were eligible. Anti- receptor-binding domain antibody concentrations were tested at least three weeks after the first vaccination and immediately before the second dose of vaccine. Information on reactogenicities was obtained via a questionnaire sent by a short message service.

RESULTS

Anti-RBD Antibody concentration at 2 and 3 months post-vaccination were significantly higher than at 1 months post-vaccination (20.14 BAU/mL (95%CI; 16.37, 24.77) at 1 month, 48.08 BAU/mL (95%CI; 42.76, 54.08) at 2 month, and 65.01 BAU/mL (95%CI; 58.88,71.61) at 3 month). Adverse events occurred in approximately 60% of participants. Factors influencing vaccine immunogenicity include age, sex, the time elapsed from the first dose of vaccine, and underlying disease with diabetes and hematologic disease.

CONCLUSION

A single dose of AZD1222 could elicit immune responses that did not decline within three months in Thai individuals. These data support the public health strategy of a delay between the prime and boost dose of AZD1222 of 4 to 12 weeks.

Reactogenicity, immunogenicity, and humoral immune response dynamics after the third dose of heterologous COVID-19 vaccines in participants fully vaccinated with inactivated vaccine

INTRODUCTION

Immunogenicity after the CoronaVac vaccine remains uncertain, especially regarding infections with the coronavirus variants of concern and waning immunity.

METHODS

This was a single-center, open-label clinical trial designed to assess the immunogenicity and safety of BBIBP-CorV, AZD1222, or BNT162b2 as the third vaccination. The key eligible criteria were individuals at least 18 years old who were fully vaccinated with two doses of CoronaVac vaccine for 2-4 months. The primary endpoint was the ratio of the geometric mean concentration (GMC) of the total anti-receptor binding domain (RBD) antibody post-vaccination compared with that pre-vaccination. The secondary endpoint was reactogenicity within 7 days.

RESULTS

Forty-one participants received AZD1222, 40 received BBIBP-CorV, and 40 received BNT162b2. The GMC of anti-RBD antibody at 2 weeks post-vaccination was 31,138.67 binding antibody units (BAU)/mL for BNT162b2, 6,412.10 BAU/mL for AZD1222, and 1,092.7 BAU/mL for BBIBP-CorV. Compared with pre-vaccination, the ratio of anti-RBD concentration was 690.24 for BNT162b2, 130.02 for AZD1222, and 17.79 for BBIBP-CorV. No potentially life-threatening adverse reaction were observed within 7 days.

CONCLUSION

A third vaccination with the heterologous vaccine, BBIBP-CorV, AZD1222, or BNT162b2, can elicit a robust immune response, without serious adverse events in participants fully vaccinated with the CoronaVac vaccine.

Immunogenicity evaluation of ChAdox1 nCov-19 (AZD1222) vaccine in solid cancer patients in Chulabhorn Hospital

INTRODUCTION

Cancer patients are more vulnerable to coronavirus disease 2019 (COVID-19) owing to their compromised immune status. However, data regarding COVID-19 vaccine safety and immune response in cancer patients are scarce.

METHOD

This prospective, age- and sex-matched, single-center cohort study included 61 cancer patients and 122 healthy control participants. Seropositivity was defined as anti-S IgG titer >0.8 units/ml. Primary end point was seroconversion rate of immunoglobulin (Ig)G antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein (anti-S IgG) in cancer patients vs. healthy control participants following the second dose of COVID-19 vaccine ChAdOx1 nCoV-19 (AZD1222).

RESULTS

After the second-dose vaccination, there was no difference in seropositivity rate between groups (57 [93.44%] patients with cancer vs. 121 [99.18%] control participants; geometric mean ratio [GMR]: 0.39; 95%CI: 0.01-10.46; p-value = 0.571). In contrast, after the first-dose vaccination, the seropositivity rate was significantly lower in the cancer patients than in the control participants (50/61 [81.97%] vs. 121/122 [99.18%]; GMR: 0.07; 95%CI: 0.01-0.71; p = 0.025). The median anti-S IgG titer after the first-and second dose vaccination were not significantly different between groups. Female sex was significantly associated with a higher anti-S IgG titer. 5FU- and taxane-based chemotherapy regimens were associated with a lower IgG titer. Side effects of vaccination were tolerable.

CONCLUSIONS

The anti-S IgG seropositivity rate after completing the second vaccine dose did not differ between the cancer patients and control participants. However, the anti-S IgG seropositivity rate after the first-dose vaccination was lower in cancer patients.

Immunogenicity and reactogenicity after heterologous prime-boost vaccination with CoronaVac and ChAdox1 nCov-19 (AZD1222) vaccines

Mass vaccination with a safe and effective vaccine may be the best way to control the COVID-19 pandemic. Heterologous prime-boost vaccination with the CoronaVac and AZD1222 vaccines may increase the immunogenicity elicited by either vaccine alone. This study sought to compare the immunogenicity of a heterologous CoronaVac and AZD1222 prime-boost with a homologous CoronaVac prime-boost. From July 13 to September 2, 2021, 88 participants were enrolled in the study. Half (n = 44) of the participants were assigned to the AZD1222/CoronaVac cohort and half were assigned to the CoronaVac/AZD1222 cohort. Both cohorts had a prime-boost interval of 4 weeks. A control group of 136 health care personnel who received the homologous CoronaVac/CoronaVac prime-boost was matched by age and sex to the experimental cohorts. The primary endpoint was the geometric mean ratio (GMR) of the anti-receptor binding domain (RBD) antibody concentration 4 weeks after the booster dose was administered. The CoronaVac/CoronaVac cohort served as the reference group. Baseline age and sex were similar, and the median age was 42.5 years. The GMR was 2.58 (95% confidence interval [CI] 1.80–3.71) and 8.69 (95% CI 6.05–12.47) in the AZD1222/CoronaVac and CoronaVac/AZD1222 cohorts, respectively. Reactogenicity was similar following prime and booster doses with the same vaccine. Findings indicated that the heterologous CoronaVac and AZD1222 prime-boost combination elicited a more robust immune response than the homologous CoronaVac prime-boost. While both heterologous prime-boost combinations showed similar reactogenicity, the immunogenicity of the CoronaVac/AZD1222 cohort was higher, indicating that the order of prime-boost vaccine administration was important.

The clinical outcomes of high neutralizing antibodies titer convalescent plasma therapy in early developed severe COVID-19 patients; a case-control study

BACKGROUND

Coronavirus disease 2019 (COVID-19) causes life-threatening pneumonia. Convalescent plasma therapy (CPT) is expected to be the effective COVID-19 treatment for passive immunity. The high neutralizing antibodies titer of CPT is needed to prove the benefit in early developed severe COVID-19.

OBJECTIVE

This case-control study evaluated transfusion efficacy and adverse events with high-titer (≥ 1:320) COVID-19 convalescent plasma compared with standard care alone in severe COVID-19 pneumonia.

RESULTS

Among 107 severe COVID-19 patients, 55 received CPT plus standard care, and 52 received standard care alone. All-cause mortality was 15.3% in the CPT group compared with 85.4% in the standard care group (p < 0.001). Univariate and multivariate analyses revealed reduced mortality with CPT (HR 0.14; 95% CI 0.07-0.31; p < 0.001 and HR 0.26; 95% CI 0.08-0.79; p = 0.018, respectively). CPT resulted in decreased use of mechanical ventilation, duration of supplemental oxygen, and high-flow oxygen requirement. Clinical and radiological outcomes improved.

CONCLUSIONS

Immediate high neutralizing antibody titer CPT is safe and reduces mortality in early developed severe COVID-19 patients. The benefit of CPT in the early course of illness is challenging and requires additional study. Trial registration Thai clinical trials registry (TCTR) no. 20220101003.

Effect of Inactivated SARS-CoV-2 Vaccines and ChAdOx1 nCoV-19 Vaccination to Prevent COVID-19 in Thai Households (VacPrevent trial)

Objectives

SARS-CoV-2 is primarily transmitted within households, with massive healthcare system burdens. The role of inactivated vaccines and ChAdOx1 nCoV-19 vaccination in the prevention of within-household transmission remains unknown.

Methods

This observational case-control study tracked 408 SARS-CoV-2 polymerase chain reaction–confirmed index cases from April to September 2021. This study aimed to prove the benefit of inactivated and ChAdOx1 nCoV-19 vaccinated index cases in preventing within-household transmissibility.

Results

A total of 1178 household contacts were investigated. A total of 231 index cases were vaccinated with inactivated or ChAdOx1 nCoV-19 vaccine, and 177 were unvaccinated. The vaccinated index cases exhibited a 7.8% risk reduction in household transmission. There was no difference in the secondary attack rate of 50.77% in unvaccinated cases compared with 46.81% in vaccinated index cases (P-value = 0.177). Those who completed the two-dose SARS-CoV-2 vaccination demonstrated a 93% reduction in household transmissibility within 14-90 days. The effectiveness for preventing household transmission was 26.09%. The 87% reduced risk of household transmissibility was observed among those who wore masks.

Conclusion

The completed two-dose SARS-CoV-2 inactivated and ChAdOx1 nCoV-19 vaccination within 14-90 days among index cases demonstrated benefits in preventing within-household transmissibility. Implementing high-efficacy vaccination and an appropriate booster dose can prevent household transmission.

Safety and Immunogenicity of the BBIBP-CorV Vaccine in Adolescents Aged 12 to 17 Years in the Thai Population: An Immunobridging Study

Adolescents can develop a severe form of Coronavirus disease 2019 (COVID-19), especially with underlying comorbidities. No study has examined the efficacy or effectiveness of inactivated COVID-19 vaccines in adolescents. This single-center, prospective cohort study was performed to evaluate the safety and effectiveness of an inactivated COVID-19 vaccine in adolescents using the immunobridging approach at Chulabhorn Hospital. The key eligibility criterion was a healthy clinical condition or stable pre-existing comorbidity. The anti-receptor-binding domain (anti-RBD) antibody concentration at 4 weeks after dose 2 of the vaccine was compared between participants aged 12 to 17 years and those aged 18 to 30 years. Safety profiles included adverse events within 7 days after each dose of the vaccine and any adverse events through 1 month after dose 2 of the vaccine. In the adolescent and adult cohorts, the geometric mean concentration of anti-RBD antibody was 102.9 binding antibody unit (BAU)/mL (95% CI, 91.0−116.4) and 36.9 BAU/mL (95% CI, 30.9−44.0), respectively. The geometric mean ratio of the adolescent cohort was 2.79 (95% CI, 2.25−3.46, p < 0.0001) compared with the adult cohort, meeting the non-inferiority criterion. The reactogenicity was slightly lower in the adolescent than in the adult cohort. No serious adverse events occurred. The inactivated COVID-19 vaccine appears safe and effective in adolescents.

Antibody levels in people with diabetes after one dose of the ChAdOx1 nCoV-19 (AZD1222) vaccine

Patients with diabetes and coexistent coronavirus disease 2019 (COVID-19) have a higher risk of COVID-19 complications. Therefore, it is critical that sustained and effective immunogenicity against COVID-19 is achieved in such patients. This study evaluates the antibody response for 56 days after the first dose of the AZD1222 vaccine in subjects with and without diabetes to assess the potential risk of delaying the second dose. This study included 282 people who received one dose of AZD1222. The geometric mean concentration of antibodies specific for severe acute respiratory syndrome coronavirus 2 IgG at 56 days was significantly (P < 0.001) lower in people with type 2 diabetes mellitus (T2D; 15.13 BAU/mL, 95% confidence interval [CI] = 10.7–21.4) than in those without diabetes (40.20 BAU/mL, 95% CI = 33.43–48.36), as confirmed by a geometric mean ratio of 0.37 (95% CI = 0.25–0.54). Weaker immune responses were also observed in diabetic patients ≥ 65 years old (10.09 BAU/mL, 95% CI = 6.09–16.71) compared with their younger counterparts (22.31 BAU/mL, 95% CI = 13.98–35.59, P = 0.034). People with T2D had weaker antibody responses than those without diabetes after the first dose of AZD1222. Older age was associated with weaker antibody responses in elderly patients with diabetes.