ReiThera’s COVID-19 Vaccine Candidate Enters Phase 2/3 Clinical Study

ReiThera’s COVID-19 Vaccine Candidate Enters Phase 2/3 Clinical Study

ROME, Italy, March 18^th, 2021 – ReiThera Srl, a biotech company dedicated to the technology development, GMP manufacturing and clinical translation of genetic vaccines and medicinal products for advanced therapies, today announces the start of its Phase 2/3 clinical study of GRAd-COV2, its vaccine candidate against the novel coronavirus (SARS-CoV-2).

The study, named COVITAR (GRAd-COV2 ITAlian Vaccine Reithera), will assess the safety, immunogenicity and efficacy of GRAd-COV2 vaccine compared to placebo for the prevention of COVID-19 in adults over 18 years of age. The first part of the study will be a Phase 2 to confirm safety and immunogenicity and select the regimen for Phase 3.

In the Phase 1 trial, a single inoculation with GRAd-COV2 was well-tolerated and generated spike-binding and neutralizing antibodies and T-cell responses at all three doses tested, with similar results in both cohorts of healthy volunteers tested – 45 adults aged 18-55 years and 45 adults aged 65-85 years. The results of the interim analysis (up to week 4 post vaccination) of this trial are being prepared for publication.

The new Phase 2 trial aims to enroll 900 participants who will be randomized 1:1:1 to receive a single dose, two doses or placebo, with vaccine or placebo being administer on Day 1 and Day 22. The trial will be conducted at 26 sites in Italy and one in Germany. The Principal Investigator for the trial is Dr. Simone Lanini at the Istituto Nazionale per le Malattie Infettive (INMI) Lazzaro Spallanzani in Rome.

An Independent Data Safety Monitoring Board and Steering Committee will make its recommendation to expand to the Phase 3 part of the study and the vaccine schedule (single or double dose) to be used. The recommendation will be based on safety results and immunogenicity data after monitoring participants for five weeks from the first vaccination in the first 450 participants enrolled (approximately 150 subjects per study arm).

The Phase 3 trial will have an adaptive design to account for the evolution of the COVID-19 pandemic, the availability of approved vaccines and characteristics of ongoing vaccination campaigns. The design scenarios are:

1. A superiority trial vs placebo on overall population; or
2. A non-inferiority trial vs the available alternative vaccine on a surrogate immunological endpoint (correlates of protection).

ReiThera will base its decision on guidance from the European Medicines Agency (EMA) on the most appropriate clinical development plan to be implemented in countries where authorized vaccines are being rolled-out.

ReiThera’s Chief Executive Officer, Antonella Folgori, said: “We were very encouraged by the results seen in our Phase 1 trial with GRAd-COV2 and delighted that we can now proceed with our Phase 2/3 trial. We are grateful to the Italian government and all those who have placed their trust in our work. There is still a great need for an effective vaccine in Italy and in other parts of the world despite the global roll out of approved vaccines. The achievements made to develop these vaccines have been amazing and we are proud to be able to contribute to this global program.”

Dr. Folgori added: “I want to thank the whole ReiThera team for their efforts in recent months as well as the clinical teams for the enthusiasm and trust that have characterized the entire Phase 1.”

“We are excited to enter into the advanced stage of development for our novel vaccine candidate. After the promising results from Phase 1 and in close collaboration with INMI Lazzaro Spallanzani, we designed and implemented a multicenter study applying innovative digital systems and a telemedicine platform. I would like to thank the Study Coordinator Dr. Lanini, all the highly motivated Investigational sites that agreed to be part of the program as well as thousands of volunteers who already applied to participate in the study,”  said Roberto Camerini, MD, Reithera’s Medical Director.

About GRAd-COV2

GRAd-COV2, the candidate vaccine against SARS-CoV-2 recently developed by ReiThera, is based on a novel and proprietary replication-defective simian (gorilla) adenoviral vector (called GRAd) encoding the full-length coronavirus spike protein (GRAd-COV2). The spike protein enables the coronavirus to enter human cells.

Simian adenoviral (SAd) vectors have widely been used as delivery agents for genetic vaccine candidates against multiple infectious diseases, including COVID-19, Ebola and RSV (Respiratory Syncytial Virus). Clinical and preclinical evidence have demonstrated that ReiThera’s vaccine technology is safe and induces robust cellular and humoral immune responses.

ReiThera’s novel GRAd vector belongs to species C adenovirus that are considered the most potent vectors for delivering vaccine and has low seroprevalence in humans. This means that GRAd vaccine immunogenicity is not diminished by pre-existing anti-human adenovirus antibodies.