ReCOV – Phase II/III Stage COVID-19 Vaccine Candidate

Summary of Clinical Trial: For our recombinant COVID-19 vaccine, ReCOV, we have completed phase I clinical trial in New Zealand, and have successively carried out multicenter phase II/III clinical trials for basic immunization and sequential booster immunization in the Philippines and the United Arab Emirates. In May 2022, ReCOV had received the approval from the NMPA for clinical trials, and the enrollment of subjects for Phase II trials of ReCOV in the Philippines was completed, and two-shot dosing for all these subjects had been completed. ReCOV has demonstrated a favorable safety profile according to the relevant safety data. At present, we are conducting data evaluation and analysis of Phase II trials in the Philippines. In August 2022, the Company was approved by the Food and Drug Administration (FDA) of the Philippines for clinical trials, and will conduct a randomized, double-blind and active-controlled Phase II clinical trial of ReCOV on healthy subjects aged 18 years or above who have received vaccination with two doses of an inactivated COVID-19 vaccine for basic immunization to compare the differences in immunogenicity and safety between ReCOV and Pfizer’s mRNA vaccine COMIRNATY®. The Company has completed all subjects enrollment and dosing.

Advantages of ReCOV

• Novel mechanism of action

ReCOV is a recombinant COVID-19 vaccine being developed by the Company with its technology platforms including the novel adjuvant and protein engineering platforms, and the adjuvant used therein is the self-developed novel adjuvant BFA03. ReCOV uses an optimized antigen, which is an NTD-RBD-foldon trimer, highly expressed by CHO cells, and can form a structure highly similar to that of the natural S protein. Compared with full-length S protein antigens, the NTD-RBD-foldon trimer antigen is enriched with key epitopes, translating to potentially stronger immunogenicity, and higher protein yield. Compared with RBD subunit vaccines, the NTD-RBD-foldon trimer antigen contains more conserved epitopes and has better cross-protection against emerging variants.

• Protection against emerging variants

 Based on the relevant studies conducted by our Group, ReCOV has shown favourable neutralizing effect and immune persistence against variants including Omicron variant and Delta variant.

• Positive safety profile and efficacy

In our phase I clinical trial in New Zealand, ReCOV has demonstrated positive safety and immunogenicity profile and no incidences of vaccine-related SAEs were experienced. Based on the partial unblinded data of Cohort I of the phase I trial of ReCOV, the GMT of SARS-CoV-2 neutralizing antibodies amounts to 1,643.2 IU/mL after two doses of ReCOV. The above information was derived from multiple clinical trials conducted for different vaccines, without the support of controlled, head-to-head clinical studies. Clinical data from Cohort 1 shows that 20 μg ReCOV may potentially induce similar or higher level of neutralizing antibodies than other marketed mRNA COVID-19 vaccines and vaccine candidates, predicting a potential positive efficacy of ReCOV in preventing SARS-CoV-2 induced diseases.

• Highly stable

Our ReCOV is stable for at least six months at room temperature and is expected to be stable for at least 24 months in the standard cold chain, based on our ongoing stability studies. The strong stability profile makes our ReCOV suitable for large population inoculation in developing countries and regions in hot climates with limited cold-chain logistics and infrastructure.