Scancell Holdings Regulatory News (SCLP)

3 January 2017

Scancell Holdings Plc

("Scancell" or the "Company")

Final SCIB1 Phase 1/2 Clinical Study Report completed on schedule

Report confirms robust survival in late stage melanoma patients

SCIB1 Phase 2 combination study on track; IND expected to be filed in H1 2017

Scancell Holdings plc, ('Scancell' or the 'Company') the developer of novel immunotherapies for the treatment of cancer, today announces that the Clinical Study Report (CSR) on the SCIB1 Phase 1/2 clinical trial in patients with Stage III/IV malignant melanoma has been completed on schedule.

The Clinical Study Report includes safety, immunology and clinical data from all patients with Stage 3/4 melanoma up to 29 October 2015, the date of the last patient's final dose in the main study. The main conclusions of the CSR are:

· SCIB1 was safe and well tolerated over a dose range of 0.4 to 8mg with no serious adverse events related to SCIB1.

· There was clear evidence of an immune response in most patients receiving SCIB1. There were significantly stronger responses to the 8mg dose than to the 2/4mg doses, indicating that this is the appropriate dose for future studies.

· Immune responses were stronger in patients without tumour present at study entry than in patients with detectable tumour; SCIB1 may therefore be particularly effective as monotherapy in early stage patients with a low tumour burden. Continued and broader responses were seen for up to two years of treatment with SCIB1, suggesting that patients may derive benefit from long term administration.

· In the nine patients with tumour present at screening who received either a 4mg or 8mg dose of SCIB1, there was evidence of clinical activity in two patients; one had a partial response by RECIST and a second patient had a greater than 30% reduction in tumour size in target lesions but progression in a non-target lesion.

· In the 20 patients with no detectable tumour at screening, disease-free survival was much higher than expected based on historical comparisons.

Updated survival and disease recurrence data are as follows:

· Currently 19 of the 20 patients with resected tumours at study entry remain alive

· Of the 16 resected patients who received 2/4mg doses of SCIB1

o Median observation time since entry is 52 months and 58 months since first diagnosis of metastatic disease

o Only five patients have progressed and one has died

o One patient in this group has now reached their 5-year post-treatment survival time point

· Of the four resected patients who received 8mg doses of SCIB1 (recruited after lower dose cohorts)

o Median observation time since entry is 21 months and 27 months since first diagnosis of metastatic disease

o All patients are alive

o Two of these patients experienced recurrence of their melanoma in Q4 2016 following early termination of their treatment in June 2016 pending manufacture of new SCIB1 supplies. One patient had received only one further dose of SCIB1 and the other had received two doses after the end of the main study period. Immune analysis from the patients recruited earlier suggests that patients may benefit from up to two years continuous treatment to effectively delay or prevent recurrence.

The Clinical Study Report will support the Company's Investigational New Drug (IND) Application for SCIB1 which is anticipated to be filed with Food and Drug Administration (FDA) in H1 2017 subject to the outcome of the pre-IND meeting planned for Q1 2017. Scancell is expecting to conduct a Phase 2 checkpoint inhibitor combination study with SCIB1 in melanoma in 2017, led by Principal Investigator Dr Keith Flaherty, Director of the Termeer Center for Targeted Therapy at Massachusetts General Hospital and Associate Professor at Harvard Medical School. A key objective of this important study will be to evaluate safety and response rates in melanoma patients administered SCIB1 in addition to a checkpoint inhibitor compared to the checkpoint inhibitor alone.

Dr Richard Goodfellow, CEO of Scancell, said: "We are pleased that the Clinical Study Report on our SCIB1 Phase 1/2 clinical trial in patients with melanoma has now been finalised, and will be able to support our US IND submission. We are very encouraged by the compelling survival data generated in this study which now demonstrates a median observation time since trial entry of more than four years for the 16 patients with resected tumours and receiving 2/4 mg doses of drug. This is supported by our long-term immune analysis that suggests continued dosing of SCIB1 may control disease in resected patients.

"We continue to expect to file our IND for SCIB1 in the first half of 2017, and to start our US clinical study of SCIB1 in combination with a checkpoint inhibitor next year. We look forward to updating the market further on these plans in due course."

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Scancell Holdings Plc

About Scancell

Scancell is developing novel immunotherapies for the treatment of cancer based on its ImmunoBody® and Moditope® technology platforms.

Scancell's first ImmunoBody®, SCIB1 is being developed for the treatment of melanoma. Data from the Phase 1/2 clinical trial demonstrate that SCIB1, when used as monotherapy, has a marked effect on tumour load, produces a melanoma-specific immune response and highly encouraging survival trend without serious side effects. In patients with resected disease there is increasing evidence to suggest that SCIB1 may delay or prevent disease recurrence.

Scancell's ImmunoBody® vaccines target dendritic cells and stimulate both parts of the cellular immune system: the helper cell system where inflammation is stimulated at the tumour site and the cytotoxic T-lymphocyte or CTL response where immune system cells are primed to recognise and kill specific cells.

Pre-clinical data on a combination of SCIB1 or SCIB2 and checkpoint inhibition (blockade of the PD-1 or CTLA-4 immune checkpoint pathways) have shown enhanced tumour destruction and significantly longer survival times than when either treatment was used alone. Experimental data suggests that the high avidity T cells induced by ImmunoBody vaccines increase expression of PDL-1 on the tumour cell surface, thereby making the tumours more sensitive to checkpoint inhibitor drugs. Re-challenging animals with tumour cells after SCIB1 treatment resulted in 100% survival suggesting that ImmunoBody induces a powerful memory response. Such an effect has not been observed with checkpoint inhibitors.

Scancell has also identified and patented a series of modified epitopes that stimulate the production of killer CD4+ T cells that destroy tumours without toxicity. The Directors believe that the Moditope® platform could play a major role in the development of safe and effective cancer immunotherapies in the future.