Safety and immunogenicity of an inactivated virus particle vaccine for SARS-CoV-2, BIV1-CovIran: findings from double-blind, randomised, placebo-controlled, phase I and II clinical trials among healthy adults

Omicron-specific and bivalent omicron-containing vaccine candidates elicit potent virus neutralisation in the animal model

Omicron variant (B.1.1.529) is able to escape from naturally acquired and vaccine-induced immunity, which mandates updating the current COVID-19 vaccines. Here, we investigated and compared the neutralising antibody induction of the ancestral variant-based BIV1-CovIran vaccine, the Omicron variant-based BIV1-CovIran Plus vaccine, and the novel bivalent vaccine candidate, BBIV1-CovIran, against the Omicron and ancestral Wuhan variants on the rat model. After inactivating the viral particles, the viruses were purified and formulated. Bivalent vaccines were a composition of 2.5 µg (5 µg total) or 5 µg (10 µg total) doses of each ansectral-based and Omicron-based monovalent vaccine. Subsequently, the potency of the monovalent and bivalent vaccines was investigated using the virus neutralisation test (VNT). The group that received three doses of the Omicron-specific vaccine demonstrated neutralisation activity against the Omicron variant with a geometric mean titer of 337.8. However, three doses of the Wuhan variant-specific vaccine could neutralise the Omicron variant at a maximum of 1/32 serum dilution. The neutralisation activity of the Omicron-specific vaccine, when administered as the booster dose after two doses of the Wuhan variant-specific vaccine, was 100% against the Omicron variant and the Wuhan variant at 1/64 and 1/128 serum dilution, respectively. Three doses of 5 µg bivalent vaccine could effectively neutralise both variants at the minimum of 1/128 serum dilution. The 10 µg bivalent vaccine at three doses showed even higher neutralisation titers: the geometric mean of 388 (95% CI 242.2-621.7) against Omicron and 445.7 (95% CI 303.3-655.0) against Wuhan. It is shown that the candidate bivalent and Omicron-specific vaccines could elicit a potent immune response against both Wuhan-Hu-1 and Omicron BA.1 variants.

Effect of homologous or heterologous vaccine booster over two initial doses of inactivated COVID-19 vaccine

INTRODUCTION

Inactivated vaccines were delivered to low- and middle-income countries during the early pandemics of COVID-19. Currently, more than 10 inactivated COVID-19 vaccines have been developed. Most inactivated vaccines contain an inactivated whole-cell index SARS-CoV-2 strain that is adjuvant. Whole virions inactivated with aluminum hydroxide vaccines were among the most commonly used. However, with the emerging of COVID-19 variants and waning of the immunity of two doses of after 3 months, WHO and many local governments have recommended the booster-dose program especially with heterologous platform vaccine.

AREA COVERED

This review was conducted through a literature search of the MEDLINE database to identify articles published from 2020 to 2023 covered the inactivated COVID-19 vaccines primary series with homologous and heterologous booster focusing on safety, immunogenicity, efficacy, and effectiveness.

EXPERT OPINION

The inactivated vaccines, especially whole virion inactivated in aluminum hydroxide appeared to be safe and had good priming effects. Immune responses generated after one dose of heterologous boost were high and able to preventing severity of disease and symptomatic infection. A new approach to inactivated vaccine has been developed using inactivating recombinant vector virus-NDV-HXP-S vaccine.

Vaccination effects on reducing COVID-19 complications in pregnancy: A large-scale report from Iran

OBJECTIVE

The objective of this study was to evaluate the effects of maternal coronavirus disease 2019 (COVID-19) vaccination on preventing severe complications of COVID-19 in pregnant women.

METHODS

A retrospective study was conducted in pregnant women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during pregnancy and/or for up to 6 weeks postpartum between September 1, 2021, to January 30, 2022. The data was retrieved from a national database. The pregnant women were divided into two groups of vaccinated and unvaccinated. The proposed outcomes (the need for hospitalization, intensive care unit admission, and mechanical ventilation and products of conception complications) were compared between the two groups.

RESULTS

Approximately 90 000 pregnant women infected with COVID-19 were included in the study. The data of the vaccinated (19 922) and unvaccinated (70 147) groups were analyzed and compared. Pregnant patients in the vaccinated group had a significantly lower rate of hospitalization (21.2% vs 29.4%) (odds ratio [OR], 0.648 [95% confidence interval (CI), 0.625-0.673], P = 0.0001) and intensive care unit admission (3.7% vs 7.8%) (OR, 0.453 [95% CI, 0.382-0.535], P = 0.0001). The need for mechanical ventilation was also lower, although not statistically significant, in the vaccinated group than in the unvaccinated group (30 of 155 [19.4%] vs 418 of 1597 [26.2%]) (OR, 0.677 [95% CI, 0.448-1.024], P = 0.063). Cesarean section (54.3% vs 58.1%) (OR, 0.856 [95% CI, 0.751-0.977], P = 0.021) and stillbirth (0.4% vs 3.6%) (OR, 0.097 [95% CI, 0.026-0.252], P = 0.0001) were also significantly lower in the vaccinated patients. Most pregnant women in the vaccinated group (18 484-96.14%) received Sinopharm BIBP COVID-19 inactivated vaccine. No significant differences were seen in the effect of different types of COVID-19 vaccines on reducing COVID-19 complications in infected pregnant patients.

CONCLUSION

Maternal COVID-19 immunization is effective in reducing COVID-19 complications in infected pregnant women.

Efficacy and safety of an inactivated virus-particle vaccine for SARS-CoV-2, BIV1-CovIran: randomised, placebo controlled, double blind, multicentre, phase 3 clinical trial

OBJECTIVE

To report the efficacy, safety, and exploratory immunogenicity findings of two 5 µg doses of the BIV1-CovIran vaccine.

DESIGN

Randomised, placebo controlled, double blind, multicentre, phase 3 clinical trial.

SETTING

In six cities of Iran, including Bushehr, Isfahan, Karaj, Mashhad, Shiraz, and Tehran. The first vaccine or placebo injection of the first participant was on 16 May 2021 in Tehran. The last vaccine or placebo injection of the last participant occurred on 15 July 2021 in Isfahan.

PARTICIPANTS

20 000 participants aged 18-75 years were randomly assigned to the intervention or placebo groups with a ratio of 2:1.

INTERVENTION

5 µg vaccine or placebo with the interval of 28 days.

MAIN OUTCOME MEASURES

Vaccine efficacy for a 90 day follow-up period, safety and explanatory immunogenicity assessment, and variant detection during the trial.

RESULTS

20 000 participants were recruited and randomly assigned to receive BIV1-CovIran (n=13 335 (66.7%)) or placebo (n=6665 (33.3%)). Participants' mean age was 38.3 (standard deviation 11.2) years, and 6913 (34.6%) were female. Among vaccinated participants that had covid-19 reported during the follow-up (median 83 days), 758 (5.9%) had symptoms, 144 (1.1%) had severe infection, and seven (0.1%) were critical. Among participants who received placebo during the follow-up, 688 (10.7%) had symptoms, 221 (3.4%) had severe infection, and 19 (0.3%) were critical. Overall efficacy was 50.2% (95% confidence interval 44.7% to 55.0%) against symptomatic covid-19, 70.5% (63.7% to 76.1%) against severe disease, and 83.1% (61.2% to 93.5%) against critical cases. Two deaths were reported in the efficacy population in the placebo group, no deaths were from the intervention group. During follow-up, 41 922 adverse events were reported: 28 782 (68.7%) were adverse reactions, of which 19 363 (67.3%) were in the intervention group. Most adverse reactions were mild or moderate in severity (grade 1 or 2) and self-limiting. No serious adverse events were related to the injections. For variant investigation, of 119 participants positive for the SARS-CoV-2 variant, 106 (89.1%) were positive for the delta variant.

CONCLUSIONS

A two dose regimen of the BIV1-CovIran vaccine conferred efficacy of 50.2% against symptomatic covid-19, 70.5% against severe disease, and 83.1% against critical disease. Vaccination was well tolerated, with no safety concerns raised.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials, IRCT20201202049567N3.

FUNDING

Shifa-Pharmed Industrial Group.

Safety and immunogenicity of a recombinant receptor-binding domain-based protein subunit vaccine (Noora vaccine™) against COVID-19 in adults: A randomized, double-blind, placebo-controlled, Phase 1 trial

The development of a safe and effective vaccine is essential to protect populations against coronavirus disease 2019 (COVID-19). There are several vaccine candidates under investigation with different mechanisms of action. In the present study, we have evaluated the safety and immunogenicity of a recombinant receptor-binding domain (RBD)-based protein subunit vaccine (Noora vaccine) against COVID-19 in adults. This Phase 1 trial is a randomized, double-blind, placebo-controlled study to evaluate the safety and immunogenicity of the recombinant RBD-based protein subunit vaccine (Noora vaccine) against COVID-19 in healthy adults volunteers. Eligible participants were included in this study after evaluating their health status and considering the exclusion criteria. They were then randomized into three groups and received three doses of vaccine (80 µg, 120 µg, and placebo) on Days 0, 21, and 35. Primary outcomes including solicited, unsolicited, and medically attended adverse events were recorded during this study. Secondary outcomes including the humoral and cellular immunity (including anti-RBD IgG antibody and neutralizing antibody) were measured on Days 0, 21, 28, 35, 42, and 49 by using the ELISA kit and the Virus Neutralization Test (VNT) was performed on day 49. Totally 70 cases were included in this Phase 1 trial and 60 of them completed the study. Safety assessments showed no severe adverse events. Local pain at the vaccine injection site occurred in 80% of the vaccinated volunteers. Induration and redness at the injection site were the other adverse reactions of this vaccine. There was no significant difference between the studied groups regarding adverse reactions. Anti-RBD IgG antibody and neutralizing antibody assessment showed significant seroconversion in comparison to the placebo group (80%, and 100% respectively, p < 0.001). The cellular immunity panel also showed mild to moderate induction of TH1 responses and the VNT showed 78% of seroprotection. The results of this Phase 1 trial showed acceptable safety without serious adverse events and significant seroconversions in the humoral and cellular immunity panel. The dose of 80 µg is an appropriate dose for injection in the next phases of the trial.

Exploring the experience of developing COVID-19 vaccines in Iran

Widespread public vaccination is one of the effective mechanisms to ensure the health and prevent deaths in societies. The coronavirus disease 2019 (COVID-19) vaccine is a stark instance in this regard. Vaccine development is a complex process requiring firm-level capabilities, various infrastructures, long-term planning, and stable and efficient policies. Due to the global demand for vaccines during the pandemic, the national capability to produce vaccines is critical. To this end, the current paper investigates influential factors, at the firm- and policy-level, in the COVID-19 vaccine development process in Iran. By adopting a qualitative research method and conducting 17 semi-structured interviews and analyzing policy documents, news, and reports, we extracted internal and external factors affecting the success and failure of a vaccine development project. We also discuss the characteristics of the vaccine ecosystem and the gradual maturity of policies. This paper draws lessons for vaccine development in developing countries at both firm and policy levels.

Variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Vaccine Effectiveness

The incidence and death toll due to SARS-CoV-2 infection varied time-to-time; and depended on several factors, including severity (viral load), immune status, age, gender, vaccination status, and presence of comorbidities. The RNA genome of SARS-CoV-2 has mutated and produced several variants, which were classified by the SARS-CoV-2 Interagency Group (SIG) into four major categories. The first category; “Variant Being Monitored (VBM)”, consists of Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Epsilon (B.1.427, B.1.429), Eta (B.1.525), Iota (B.1.526), Kappa (B.1.617.1), Mu (B.1.621), and Zeta (P.2); the second category; “Variants of Concern” consists of Omicron (B.1.1.529). The third and fourth categories include “Variants of Interest (VOI)”, and “Variants of High Consequence (VOHC)”, respectively, and contain no variants classified currently under these categories. The surge in VBM and VOC poses a significant threat to public health globally as they exhibit altered virulence, transmissibility, diagnostic or therapeutic escape, and the ability to evade the host immune response. Studies have shown that certain mutations increase the infectivity and pathogenicity of the virus as demonstrated in the case of SARS-CoV-2, the Omicron variant. It is reported that the Omicron variant has >60 mutations with at least 30 mutations in the Spike protein (“S” protein) and 15 mutations in the receptor-binding domain (RBD), resulting in rapid attachment to target cells and immune evasion. The spread of VBM and VOCs has affected the actual protective efficacy of the first-generation vaccines (ChAdOx1, Ad26.COV2.S, NVX-CoV2373, BNT162b2). Currently, the data on the effectiveness of existing vaccines against newer variants of SARS-CoV-2 are very scanty; hence additional studies are immediately warranted. To this end, recent studies have initiated investigations to elucidate the structural features of crucial proteins of SARS-CoV-2 variants and their involvement in pathogenesis. In addition, intense research is in progress to develop better preventive and therapeutic strategies to halt the spread of COVID-19 caused by variants. This review summarizes the structure and life cycle of SARS-CoV-2, provides background information on several variants of SARS-CoV-2 and mutations associated with these variants, and reviews recent studies on the safety and efficacy of major vaccines/vaccine candidates approved against SARS-CoV-2, and its variants.

Efficacy and safety of COVID-19 vaccines: A network meta-analysis

OBJECTIVE

Several vaccines showed a good safety profile and significant efficacy against COVID-19. Moreover, in the absence of direct head to head comparison between COVID-19 vaccines, a network meta-analysis that indirectly compares between them is needed.

METHODS

Databases PubMed, CENTRAL, medRxiv, and clinicaltrials.gov were searched. Studies were included if they were placebo-controlled clinical trials and reported the safety profile and/or effectiveness of COVID-19 vaccines. The quality of the included studies was assessed using the Revised Cochrane risk-of-bias tool for randomized trials and the Revised Cochrane risk-of-bias tool for nonrandomized trials.

RESULTS

Forty-nine clinical trials that included 421,173 participants and assessed 28 vaccines were included in this network meta-analysis. The network meta-analysis showed that Pfizer is the most effective in preventing COVID-19 infection whereas the Sputnik Vaccine was the most effective in preventing severe COVID-19 infection. In terms of the local and systemic side, the Sinopharm and V-01 vaccines were the safest.

CONCLUSION

We found that almost all of the vaccines included in this study crossed the threshold of 50% efficacy. However, some of them did not reach the previously mentioned threshold against the B.1.351 variant while the remainder have not yet investigated vaccine efficacy against this variant. Since each vaccine has its own strong and weak points, we strongly advocate continued vaccination efforts in individualized manner that recommend the best vaccine for each group in the community which is abundantly required to save lives and to avert the emergence of future variants.