Scancell : Interim Report 31st October 2022

25 January 2023

Scancell Holdings plc

("Scancell" or the "Company")

Interim Results for the 6 months ended 31 October 2022

Strong clinical progress with ongoing ModiFY and SCOPE trials; further safety, immune and clinical

response data expected in 2023

Signed licensing agreement with Genmab to develop and commercialise an anti-glycan mAb providing

strong commercial validation of the Company's scientific approach and strategy

Scancell Holdings plc (AIM: SCLP), the developer of novel immunotherapies for the treatment of cancer and infectious disease, today announces its interim results for the 6 months ended 31 October 2022 and provides a business update on progress achieved to date.

Highlights (including post period):

Vaccines:

• Fourteen patients enrolled and dosed in the expansion phase of the monotherapy arms in the multicentre Phase 1/2 Modi-1 clinical trial (ModiFY). First patient dosed in Cohort 3 of ModiFY in combination with a checkpoint inhibitor (CPI). There have been no safety issues to date.
• Expansion of SCIB1 Phase 2 combination trial (SCOPE) protocol to include SCIB1 in combination with checkpoint doublet therapy leading to significantly increased recruitment rate.
• In-licensedthe SNAPvax™ technology from Vaccitech plc to formulate and manufacture Modi-2, with the aim of initiating a Phase 1 clinical study in cancer patients during H1 2024.
• Recruitment completed in COVIDITY Phase 1 clinical trial in South Africa, with safety and immunogenicity data expected in Q1 2023, providing read across to our second-generation ImmunoBody® platform.

Antibodies:

• Plans to take two GlyMab® monoclonal antibodies (mAbs), a redirecting T-cell bispecific (TCB) antibody and a T cell costimulatory mAb into the clinic, with initiation of TCB manufacturing in H1 2023 prior to clinical evaluation in 2024.
• Signed licensing agreement with Genmab to develop and commercialise an anti-glycan mAb, with the Company being eligible to receive milestone payments of up to $208 million for each product developed and commercialised, up to a maximum of $624 million if Genmab develops and commercialises products across all defined modalities.
• AvidiMab® technology continues to be applied to the Company's internal programmes whilst evaluating how AvidiMab® could be used to enhance the efficacy of third-party antibodies.
• Preclinical data on GlyMab® and AvidiMab® antibody platforms presented at PEGS Europe and EuroMAbNet Annual Meeting in H2 2022.

Corporate:

• John Chiplin has announced he will resign as Executive Chairman for personal reasons but is staying on for an interim period until a new Chair is appointed.
• Dr Richard Goodfellow, stepped down a Board Director at the 2022 Annual General Meeting (AGM).
• Susan Clement Davies, an independent Non-Executive Director and Chair of the Audit Committee, appointed as Deputy Chair.

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Financial:

• Reported loss for the 6-month period to 31 October 2022 of £3.2 million (31 October 2021 profit of £3.2 million).
• Received licence fee of £5.3 million relating to the up-front payment receivable from Genmab following the signing of the licence agreement in October 2022.
• Group cash balance at 31 October 2022 was £24.0 million (April 2022: £28.7 million) with a cash runway until Q1 2024.

Prof Lindy Durrant, Chief Executive Officer, Scancell, commented:

"We are pleased to report another period of progress for Scancell, including strong clinical and commercial developments. We have continued to advance our ModiFY Phase 1/2 trial for Modi-1 and the SCOPE Phase 2 trial for SCIB1 and expect to generate safety, immune and clinical response results during 2023. During the period, we also continued to progress our earlier stage pipeline having signed an in-licensing agreement with Vaccitech.

"It has been a defining period for our proprietary antibody platform as we have signed a licensing agreement for one of our anti-glycan mAbs with Genmab, providing strong validation of the platform and the Company's scientific approach. We remain one of only a few companies worldwide that has the capability to produce high affinity, humanised anti-glycan antibodies and continue to evaluate options and potential agreements for the Company's GlyMab® antibodies in order to provide further third-party validation, develop the business and generate revenues. We would like to thank our shareholders for their continued support over the past 6 months and look forward to updating the market on our future clinical and operational progress during 2023."

A full copy of the announcement can be found on the Scancell website: www.scancell.co.uk

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

For further information, please contact:
Scancell Holdings plc	[phone]
Dr John Chiplin, Executive Chairman
Professor Lindy Durrant, CEO
Stifel Nicolaus Europe Limited (Nominated Adviser and Joint Broker)	[phone]
Nicholas Moore/Samira Essebiyea/William Palmer-Brown (Healthcare
Investment Banking)
Nick Adams/Nick Harland (Corporate Broking)
Panmure Gordon (UK) Limited (Joint Broker)	[phone]
Freddy Crossley/Emma Earl (Corporate Finance)
Rupert Dearden (Corporate Broking)
FTI Consulting	[phone]
Simon Conway/Rob Winder/Alex Davis

About Scancell

Scancell is a clinical stage biopharmaceutical company that is leveraging its proprietary research, built up over many years of studying the human adaptive immune system, to generate novel medicines to treat significant unmet needs in cancer and infectious disease. The Company is building a pipeline of innovative products by utilising its four technology platforms: Moditope® and ImmunoBody® for vaccines and GlyMab® and AvidiMab® for antibodies.

Adaptive immune responses include antibodies and T cells (CD4 and CD8), both of which can recognise damaged or infected cells. In order to destroy such cancerous or infected cells, Scancell uses either vaccines to induce immune responses or monoclonal antibodies (mAbs) to redirect immune cells or drugs. The

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Company's unique approach is that its innovative products target modifications of proteins and lipids. For the vaccines (Moditope® and ImmunoBody®) this includes citrullination and homocitrullination of proteins, whereas its mAb portfolio targets glycans or sugars that are added onto proteins and / or lipids (GlyMab®) or enhances the potency of antibodies and their ability to directly kill tumour cells (AvidiMab®).

For further information about Scancell, please visit: https://www.scancell.co.uk/

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CHAIRMAN'S STATEMENT

I am pleased to report the Group's interim results for the 6-month period ended 31 October 2022. During the period, Scancell has continued to make good clinical trial progress with recruitment accelerating in the ongoing ModiFY and SCOPE trials, and the completion of dosing in the COVIDITY Phase 1 study. In addition, we have signed two encouraging deals, with Genmab which has accelerated one of our antibodies into development, and post-period with Vaccitech plc to streamline the future manufacture of Modi-2. In our early stage pipeline, it is exciting to see Scancell's T cell bispecific (TCB) redirecting programme advancing towards identification of the lead product for our in-house clinical development. We are indebted to our staff in all aspects of the Company for their hard work, creative ideas and thoughtful approach to working with their fellow employees to help achieve this strong progress.

Set out below is a summary of progress that has been made across our innovative and proprietary vaccine and antibody platforms.

VACCINES

Moditope® platform

Moditope® is a versatile proprietary cancer vaccine platform that targets stress-inducedpost-translational modifications (siPTMs) of proteins. This discovery has allowed us to develop a completely new class of potent and selective therapeutic vaccines. Examples of such modifications include citrullination, an enzyme-based conversion of arginine to citrulline, and homocitrullination, in which lysine residues are converted to homocitrulline. Vaccination with peptides containing these modifications have been demonstrated to induce potent CD4 cytotoxic T cells that induce anti-tumour activity without any associated toxicity in preclinical models.

Modi-1

Modi-1, which targets citrullinated cancer antigens, is the first therapeutic vaccine candidate to emerge from Scancell's Moditope® platform. The ModiFY study is a multicentre Phase 1/2 first-in-human clinical trial, with Modi-1 being administered alone or in combination with checkpoint inhibitors (CPIs) in patients with head and neck, triple negative breast and renal tumours, as a monotherapy in patients with ovarian cancer where there are no approved CPI therapies and in patients with the other tumour types where CPIs are not indicated. This open label study will recruit up to 138 patients in up to 20 clinical trial sites across the UK. Nine sites are actively recruiting with another three being set up and expected to initiate screening during 2023. To date, 21 patients have been immunised in the ModiFY study and a further 16 have been recruited.

As previously reported, Cohort 1 of the study confirmed the safety profile of a low dose of two citrullinated vimentin peptides. The objective for Cohort 2 of the trial was to assess the safety of the two citrullinated vimentin peptides plus an enolase peptide at a higher dose. We are pleased to announce that all three patients in Cohort 2 have now successfully received multiple doses and the injections were well tolerated with no safety concerns. The head and neck patient in Cohort 2 has now shown a confirmed partial response with further regression of their tumour at week 16 whilst one ovarian patient in Cohort 1 and one in Cohort 2 have stable disease.

Based on the safety data analysed from Cohort 2, post-period the ModiFY trial was expanded at this dose for Modi-1 monotherapy in three tumour types. To date, 13 ovarian, two breast and three head and neck patients, including one in Cohort 3 in combination with a CPI, have been dosed with no safety issues. Modi-1 stimulates CD4 T cells which may directly impact tumour growth. However, in some patients these T cells may need to be protected by CPIs if the tumour environment is highly immunosuppressive.

Modi-1 peptides are linked to AMPLIVANT®, a potent adjuvant which enhanced the immune response 10-100- fold and resulted in highly efficient tumour clearance, including protection against tumour recurrence, in preclinical models. AMPLIVANT® is the subject of a worldwide licensing and collaboration agreement with ISA Pharmaceuticals for the manufacturing, development, and commercialisation of Modi-1.

The Company expects further safety, immunogenicity and efficacy data from the ModiFY study to be available during 2023.

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Modi-2

Modi-2, which targets homocitrullinated cancer antigens, is the second therapeutic vaccine candidate from the Company's Moditope® platform and has the potential to address different cancer indications to Modi-1, including tumours with a particularly immunosuppressive environment. During the period, internal preclinical research and formulation development work has continued to progress Modi-2 towards the clinic.

Post period, we were pleased to announce that we had in-licensed the SNAPvax™ technology from Vaccitech plc, a clinical-stage biopharmaceutical company engaged in the discovery and development of novel immunotherapies and vaccines.

The SNAPvax™ technology enables peptides to self-assemble with TLR-7/8a, a powerful adjuvant, to promote strong T cell responses and is proven to successfully overcome historic formulation issues associated with immunogenic peptide antigens, which are often highly hydrophobic and prone to manufacturing challenges with conventional formulations. For Modi-2, the Company plans to use SNAPvax™ to co-deliver homocitrullinated peptide antigens and TLR-7/8a adjuvants in self-assembling nanoparticles designed to prime tumour killing T cells. The Company expects that the combination of Scancell's Modi-2 with a highly effective platform for inducing T cells will lead to a potentially superior therapeutic vaccine candidate.

Homocitrullination is a process that occurs by a different mechanism compared to citrullination (Modi-1) and is therefore applicable to a distinct set of highly immune suppressed tumours. Scancell will leverage its deep understanding of T cell immunology and cancer immunotherapy together with its strong development capabilities to bring Modi-2 to clinical validation, adding value to the entire Moditope® platform. The agreement with Vaccitech plc, signed in November 2022, will allow Scancell to formulate and manufacture Modi-2, with the aim of initiating a Phase 1 clinical study in cancer patients in H1 2024.

ImmunoBody® platform

Scancell's ImmunoBody® immunotherapy platform uses the body's immune system to identify, attack and destroy tumours. This is achieved by delivering a DNA plasmid to enhance the uptake and presentation of cancer antigens to harness high avidity T cell responses. Each ImmunoBody® vaccine can be designed to target a particular cancer in a highly specific manner, offering the potential for enhanced efficacy and safety compared with more conventional approaches. These vaccines have the potential to be used as monotherapy or in combination with CPIs and other agents. The Board believe that this platform has the potential to enhance tumour destruction, prevent disease recurrence and extend survival rates for patients.

Scancell's ImmunoBody® vaccine approach can also be exploited to induce immune responses against infectious diseases. As research data emerged at the beginning of the COVID-19 pandemic, it was clear that the induction of potent and activated T cells could play a critical role in the development of long-term immunity and clearance of virus-infected cells. Scancell therefore used its proven cancer vaccine concept to design a vaccine against SARS-CoV-2, the virus that causes COVID-19.

SCIB1 and iSCIB1+

SCIB1 is the lead product from the Company's ImmunoBody® immunotherapy platform, which uses the body's immune system to identify, attack and destroy tumours and is currently being evaluated in a Phase 2 clinical trial ('SCOPE') in the UK in combination with a CPI for the treatment of metastatic melanoma.

Following the approval of a protocol amendment by the UK's Medicines and Healthcare products Regulatory Agency (MHRA), the trial now includes a cohort of melanoma patients who will receive SCIB1 plus doublet therapy consisting of ipilimumab (Yervoy®) plus nivolumab (Opdivo®), in addition to the cohort who will receive SCIB1 with pembrolizumab (Keytruda®). This protocol amendment reflects changes in the current treatment landscape for metastatic melanoma patients. The Phase 2 study is designed to assess whether the addition of SCIB1 treatment to CPI standard of care results in an improvement in outcomes for patients with metastatic disease. The primary objectives of the SCOPE trial are tumour response rate, progression-free survival and overall survival in patients with advanced melanoma.

Under the updated protocol the Company is now also testing the SCIB1 vaccine delivered via needle-free injection, using a PharmaJet® device. Prior to the amendment, SCIB1 had been delivered using electroporation to enhance the uptake and presentation of the DNA vaccine to the immune system and, although electroporation is a proven delivery method, the Company believes that needle-free injection (such as the PharmaJet® device) could provide enhanced patient acceptance and uptake. Eight sites are currently recruiting

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