Vaccibody is initiating a phase 1/2, open label, dose escalation trial in healthy adult volunteers to determine safety and immunogenicity of two SARS CoV-2 virus DNA vaccine candidates.

Vaccibody’s development strategy is to develop second-generation SARS CoV-2 vaccines that may respond to the emerging threats of evolving variants with reduced sensitivity to first generation vaccines that were developed using the 2020 prototype spike protein.

“It is an important milestone, and we are proud to demonstrate the rapid development and fast turn-around time for our Vaccibody technology platform with these second-generation CoV-2 vaccine candidates.”

The trial is a continuation of the pre-clinical work published by Vaccibody in December 2020 showing that pre-clinical vaccine candidates induced rapid, strong and long-lasting neutralizing antibodies, as well as multifunctional, dominant CD8+ T cell and Th1 CD4+ T cell responses in mice, after a single dose, states the company in a press release.

“The two SARS CoV-2 vaccine candidates are the first results of our vaccine strategy within infectious diseases. It is an important milestone, and we are proud to demonstrate the rapid development and fast turn-around time for our Vaccibody technology platform with these second-generation CoV-2 vaccine candidates,” says Michael Engsig, CEO of Vaccibody.

An RBD candidate and a T-cell candidate

The 2-armed trial takes its outset in two development candidates designed around the modular Vaccibody technology platform, targeting antigens to antigen presenting cells. The dose escalation trial will enroll both pre-treated and treatment naïve subjects.

The first new drug candidate is an RBD candidate encoding the receptor binding domain (RBD) derived from the SARS-CoV-2 virus. The RBD domain is responsible for binding to the ACE2 receptor and is a relevant target for neutralizing antibodies. It is expected to elicit protection against disease by inducing neutralizing antibodies alongside a balanced CD8+ and Th1 biased CD4+ response.

The second candidate builds on emerging evidence showing that T cell responses are likely to play an essential role in SARS-CoV-2 immunity and viral clearance, and that T cell-epitopes are less prone to immune evasion than the surface-exposed spike epitopes including current and future variants of concern. The candidate encodes multiple immunogenic and conserved T cell epitopes spanning multiple antigens across the SARS-CoV-2 genome.

First patient expected to be dosed in early Q4 2021

“We are very excited about this upcoming trial. We are in close and frequent dialogue with regulatory and scientific advice consultations with the Norwegian Medicines Agency (NoMA). Vaccibody consults their experts in a rolling review of key documents to be included in the application for the trial. The primary objective of this flexible process is to proactively align expectations for the approval of the trial to allow for a rapid initiation of the clinical activities,” says Chief Medical Officer of Vaccibody, Siri Torhaug.

The trial is currently in the planning phase and with the CTA (Clinical Trial Application) expected to be submitted in Q3 2021 and the first patient expected to be dosed in early Q4 2021. The trial plans to enroll approximately 100-200 patients.

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