Scancell Holdings Regulatory News (SCLP)

31 January 2022

Scancell Holdings plc

("Scancell" or the "Company")

Update on COVIDITY Phase 1 clinical trial in South Africa

First patient dosed with second COVIDITY vaccine candidate (SCOV2)

Preclinical studies demonstrate strong immunity against Omicron

Scancell Holdings plc (AIM: SCLP), the developer of novel immunotherapies for the treatment of cancer and infectious disease, today announces further progress of the Phase 1 COVIDITY clinical trial being conducted at the University of Cape Town (UCT) Lung Institute in South Africa.

The objectives of the first part of the trial are to assess the safety and immunogenicity of two vaccine candidates, SCOV1 and SCOV2, in healthy, vaccine-naïve subjects, prior to testing as a booster in volunteers who have already received an approved vaccine. To date, 16 subjects have been enrolled and the SCOV1 immunisations have been well tolerated, with no safety concerns. As per protocol, we can now report that the first subject has received their first injection with the second vaccine candidate SCOV2, following two injections with SCOV1.

As announced at the Company's interim results, due to the high case numbers of the Omicron variant in South Africa, recruitment has been slow to date but, now the country's wave of infections has passed, screening is continuing at an increased rate, with further safety and immunogenicity data still expected to be available in H1 2022.

Scancell has previously shown in preclinical models that both SCOV1 and SCOV2 induce high titre antibodies and potent T cells against both the S and N antigens, and that these responses cross-reacted with the Delta variant. The Company has now confirmed in preclinical studies that although both vaccines induced responses against the Omicron variant, the strongest responses were seen with SCOV2.

Honorary Prof Rod Dawson, Managing Director of the University of Cape Town Lung Institute, commented: "There is still a need for additional SARS-CoV-2 vaccines that are safe and effective to achieve long-lasting protection against new and emerging variants. The UCT Lung Institute remains highly motivated to investigate the clinical potential of the SCOV1 and SCOV2 vaccines with our colleagues at Scancell."

Prof Lindy Durrant, Chief Executive Officer, Scancell, commented: "We are delighted that the first subject has now received a SCOV2 injection in the COVIDITY Phase 1 clinical trial. The Scancell team and collaborators remain convinced that a more durable and broader-acting vaccine is required to combat the global pandemic and we are encouraged by the emerging data supporting the use of our vaccines against new variants."

This announcement contains inside information for the purposes of Article 7 of Regulation (EU) 596/2014 (MAR).

About Scancell

Scancell is developing novel immunotherapies for the treatment of cancer based on its technology platforms, ImmunoBody®, Moditope® and AvidiMab™, with four products in multiple cancer indications and development of a vaccine for COVID-19.

ImmunoBody® vaccines target dendritic cells and stimulate both CD4 and CD8 T cells with the ability to identify, target and eliminate cancer cells. These cancer vaccines have the potential to be used as monotherapy or in combination with checkpoint inhibitors and other agents. The Directors believe that this platform has the potential to enhance tumour destruction, prevent disease recurrence and extend survival.

DNA vaccine against COVID-19: As research data emerges, it is becoming increasingly clear that the induction of potent and activated T cells may play a critical role in the development of long-term immunity and clearance of virus-infected cells. Initial research is underway and Scancell has initiated a Phase 1 clinical trial known as COVIDITY in October 2021. The COVIDITY programme, which has received funding from Innovate UK. is a collaboration between Scancell and scientists in the newly established Centre for Research on Global Virus Infections and the new Biodiscovery Institute at the University of Nottingham, and Nottingham Trent University.

Moditope® represents a completely new class of potent and selective immunotherapy agents based on stress-induced post-translational modifications (siPTM). Examples of such modifications are citrullination, an enzyme-based conversion of arginine to citrulline, and homocitrullination (or carbamylation), in which lysine residues are converted to homocitrulline. Expression of peptides containing these modifications have been demonstrated to induce potent CD4 cytotoxic T cells to eliminate cancer. The Directors believe that this platform has the potential to eradicate hard to treat solid tumours.

AvidiMab™ has broad potential to increase the avidity or potency of any therapeutic monoclonal antibody (mAb) including those being developed for autoimmune diseases, as well as cancer. Scancell's development pipeline includes mAbs against specific tumour-associated glycans with superior affinity and selectivity profiles, that have now been further engineered using the Company's AvidiMab™ technology; this confers the Scancell mAbs with the ability to directly kill tumour cells. The tumour-specific mAbs can also be used to deliver cytotoxic payload to cancer or to redirect T cells.