Estimated Effectiveness of a Primary Cycle of Protein Recombinant Vaccine NVX-CoV2373 Against COVID-19

Clinical development of SpikoGen®, an Advax-CpG55.2 adjuvanted recombinant spike protein vaccine

Recombinant protein vaccines represent a well-established, reliable and safe approach for pandemic vaccination. SpikoGen® is a recombinant spike protein trimer manufactured in insect cells and formulated with Advax-CpG55.2 adjuvant. In murine, hamster, ferret and non-human primate studies, SpikoGen® consistently provided protection against a range of SARS-CoV-2 variants. A pivotal Phase 3 placebo-controlled efficacy trial involving 16,876 participants confirmed the ability of SpikoGen® to prevent infection and severe disease caused by the virulent Delta strain. SpikoGen® subsequently received a marketing authorization from the Iranian FDA in early October 2021 for prevention of COVID-19 in adults. Following a successful pediatric study, its approval was extended to children 5 years and older. Eight million doses of SpikoGen® have been delivered, and a next-generation booster version is currently in development. This highlights the benefits of adjuvanted protein-based approaches which should not overlook when vaccine platforms are being selected for future pandemics.

Comprehensive Review of COVID-19: Epidemiology, Pathogenesis, Advancement in Diagnostic and Detection Techniques, and Post-Pandemic Treatment Strategies

At present, COVID-19 remains a public health concern due to the ongoing evolution of SARS-CoV-2 and its prevalence in particular countries. This paper provides an updated overview of the epidemiology and pathogenesis of COVID-19, with a focus on the emergence of SARS-CoV-2 variants and the phenomenon known as 'long COVID'. Meanwhile, diagnostic and detection advances will be mentioned. Though many inventions have been made to combat the COVID-19 pandemic, some outstanding ones include multiplex RT-PCR, which can be used for accurate diagnosis of SARS-CoV-2 infection. ELISA-based antigen tests also appear to be potential diagnostic tools to be available in the future. This paper also discusses current treatments, vaccination strategies, as well as emerging cell-based therapies for SARS-CoV-2 infection. The ongoing evolution of SARS-CoV-2 underscores the necessity for us to continuously update scientific understanding and treatments for it.

Estimating All-Cause Deaths Averted in the First Two Years of the COVID-19 Vaccination Campaign in Italy

Comparing deaths averted by vaccination campaigns is a crucial public health endeavour. Excess all-cause deaths better reflect the impact of the pandemic than COVID-19 deaths. We used a seasonal autoregressive integrated moving average with exogenous factors model to regress daily all-cause deaths on annual trend, seasonality, and environmental temperature in three Italian regions (Lombardy, Marche and Sicily) from 2015 to 2019. The model was used to forecast excess deaths during the vaccinal period (December 2020-October 2022). We used the prevented fraction to estimate excess deaths observed during the vaccinal campaigns, those which would have occurred without vaccination, and those averted by the campaigns. At the end of the vaccinal period, the Lombardy region proceeded with a more intensive COVID-19 vaccination campaign than other regions (on average, 1.82 doses per resident, versus 1.67 and 1.56 in Marche and Sicily, respectively). A higher prevented fraction of all-cause deaths was consistently found in Lombardy (65% avoided deaths, as opposed to 60% and 58% in Marche and Sicily). Nevertheless, because of a lower excess mortality rate found in Lombardy compared to Marche and Sicily (12, 24 and 23 per 10,000 person-years, respectively), a lower rate of averted deaths was observed (22 avoided deaths per 10,000 person-years, versus 36 and 32 in Marche and Sicily). In Lombardy, early and full implementation of adult COVID-19 vaccination was associated with the largest reduction in all-cause deaths compared to Marche and Sicily.

Risk of SARS-CoV-2 breakthrough infection following NVX-CoV2373 and BNT162b2 vaccinations in Korean Adults: A population-based observational study

South Korea experienced a low prevalence of SARS-CoV-2 until the emergence of the omicron in early 2022, triggering a major community epidemic. To evaluate effectiveness of NVX-CoV2373 and BNT162b2 vaccines in Korean population, we conducted an observational study utilizing individual-level case data on laboratory-confirmed SARS-CoV-2 infection, along with vaccination record. A total of 47,078 recipients of NVX-CoV2373 vaccine and 7,561 recipients of BNT162b2 vaccine were eligible for the study. Thirty days post-second doses, COVID-19 rates were 7.9% (595 out of 7561) of NVX-CoV2373 recipients and 8.6 % (647 out of 7561) of BNT162b2 recipients experienced COVID-19. NVX-CoV2373 rates increased to 9.8 % and 11.2 % at 60 and 90 days, while BNT162b2 rates were 10.5 % and 11.3 % at the same intervals. The 22-weeks risk ratios for recipients of the NVX-CoV2373 vaccine as compared with recipients of the BNT162b2 vaccine were 1.11 (95 % CI, 0.99 to 1.25) for laboratory-confirmed SARS-CoV-2 infection. Continued monitoring is essential to evaluate the duration of protection across different vaccine platforms and schedules.

Population-Based Evaluation of Vaccine Effectiveness against SARS-CoV-2 Infection, Severe Illness, and Death, Taiwan

Taiwan provided several COVID-19 vaccine platforms: mRNA (BNT162b2, mRNA-1273), adenoviral vector-based (AZD1222), and protein subunit (MVC-COV1901). After Taiwan shifted from its zero-COVID strategy in April 2022, population-based evaluation of vaccine effectiveness (VE) became possible. We conducted an observational cohort study of 21,416,151 persons to examine VE against SARS-CoV-2 infection, moderate and severe illness, and death during March 22, 2021-September 30, 2022. After adjusting for age and sex, we found that persons who completed 3 vaccine doses (2 primary, 1 booster) or received MVC-COV1901 as the primary series had the lowest hospitalization incidence (0.04-0.20 cases/100,000 person-days). We also found 95.8% VE against hospitalization for 3 doses of BNT162b2, 91.0% for MVC-COV1901, 81.8% for mRNA-1273, and 65.7% for AZD1222, which had the lowest overall VE. Our findings indicated that protein subunit vaccines provide similar protection against SARS-CoV-2---associated hospitalization as mRNA vaccines and can inform mix-and-match vaccine selection in other countries.