Type: Multiple epitope or “multitope” peptide-based vaccine designed to activate both B and T-cell arms of the immune system. UB-612 consists of the Spike protein S1 subunit Receptor Binding Domain (RBD) genetically fused to a single chain Fc domain of human IgG1 (S1-RBD-sFc), combined with proprietary peptides representing T helper (Th) and cytotoxic T-cell (CTL) epitopes on S2 subunit, Membrane and Nucleocapsid structural protein components of SARS-CoV-2. These Th and CTL peptides are selected based on their predicted binding to human MHC I and II, which would allow for the induction of memory recall and T-cell activation and effector functions. The vaccine candidate is formulated with CpG1 and aluminum phosphate (AdjuPhos®) to induce a Th1 prone response.
Status: COVAXX said September 28 that the first healthy adult volunteers were safely dosed in the company’s Phase I trial (NCT04545749), an open-label, dose-escalation study being conducted in Taiwan. The open-label trial is designed to evaluate the safety, tolerability, and immunogenicity of UB-612. The trial has begun enrolling 60 healthy male and female adults, from 20–55 years of age, in three groups of 20 subjects. Each subject will receive ascending dose levels of UB-612 in two intramuscular injections spaced 28 days apart. Dose groups will be staggered so that safety can be rapidly assessed before ascending to the next dose level.
COVAXX said the trial is partly supported by a grant from the Ministry of Health and Welfare in Taiwan of up to NTD 430 million (approximately $15 million). The trial expands on international collaborations of COVAXX, which include plans to conduct large scale human efficacy clinical trials in Brazil with Dasa, the largest diagnostic medicine company in Brazil and Latin America, and in the U.S. with The University of Nebraska Medical Center.
Results from the Phase I study, which will be evaluated through interim analyses, will enable COVAXX to select an appropriate dose and rapidly progress to a Phase II/III clinical trial, COVAXX chief scientific officer Farshad Guirakhoo said.
UB-612 is based on a peptide-based platform first deployed by United Biomedical. The vaccine platform has been commercialized successfully in more than 500 million doses annually and 5 billion doses cumulatively in animal health indications for infectious disease. UB-612 does not require additional infrastructure such as freezers or liquid nitrogen tanks to store materials at temperatures beyond -80°C.
“When we look at the titer for neutralization and we compare it in preclinical to preclinical head to head against other vaccines out there,” Peter H. Diamandis, PhD, vice chairman, COVAXX, told GEN in September, “we’re not at 40, or 500 to 1,000. We’re at greater than 32,000. We’re talking about orders of magnitudes higher in terms of neutralizing titer. If you have high immunogenicity and super high neutralizing titers, this is because of the rational design—we have six epitopes. The multitope design doesn’t just attack COVID-19 and stop it from one angle, one protein. It’s coming at it from multiple angles.”
Co-founder and Co-CEO Mei Mei Hu added: I think of them like our platform is like Legos, or an operating system, and each new disease indication is like an app or a new Lego box. Everything is designed from scratch, but they’re using the same types of building blocks. So, for COVID-19, we were actually fortunate because we had worked on SARS before. So we actually knew a lot about this type of coronavirus, and that’s why we’re able to rapidly put together something in just a couple months.
COVID-19: 200 Candidates and Counting
To navigate through the >200 potential therapeutic and vaccine options for COVID-19, GEN has grouped the candidates into four broad categories based on their developmental and (where applicable) clinical progress:
● FRONT RUNNER – the most promising therapeutics/vaccines based on clinical progress, favorable data or both.
● DEFINITELY MAYBE – earlier phases with promising partners, or more advanced candidates in development that have generated uneven data
● KEEPING AN EYE ON… – interesting technology, attracting notable partners, or both, but preliminary data.
● TOO SOON TO TELL – longshots pending additional experimental and/or clinical data.
GEN has also tagged the most common treatment types: