Adaptimmune Updates Data from its Phase 1 Trial for Liver Cancer at ILCA Showing Clinical Benefit

- One complete response, and a disease control rate of 64% with stable disease for ≥16 weeks in two patients, as of the data cutoff -

- Data presented today at the International Liver Cancer Association meeting at 12:25 p.m. CET -

PHILADELPHIA and OXFORDSHIRE, United Kingdom, Sept. 05, 2021 (GLOBE NEWSWIRE) -- Adaptimmune Therapeutics plc (Nasdaq: ADAP), a leader in cell therapy to treat cancer, announced updated data from its Phase 1 ADP-A2AFP trial for patients with liver cancer at ILCA.

“We have seen significant antitumor activity with this first-generation product targeting AFP that is encouraging for the potential of cell therapy for the treatment of liver cancer in these heavily pre-treated patients with late-stage disease,” said Elliot Norry, Adaptimmune’s Chief Medical Officer. “We reported a complete response in one patient, and tumor reductions with stable disease that has lasted more than 16 weeks in two patients as well as disease control in most patients at the target dose. We are continuing the expansion phase and will update when new data becomes available.”

“Despite the recent advances, we need more and better systemic therapies for liver cancer,” said Dr. Bruno Sangro of Clinica Universidad de Navarra. “The first results from this cell therapy trial are of great interest since they indicate obvious antitumor activity in some patients. This treatment has generally been safely applied even to cirrhotic patients.”

Oral Presentation Today at ILCA
Dr. Bruno Sangro presented data from Cohort 3 and the expansion phase of the ADP-A2AFP Phase 1 trial during an oral presentation today at ILCA. A replay will be available through the congress web site.

Topline results from the ADP-A2AFP Phase 1 trial as of the April 5, 2021 data cutoff
Efficacy

• Thirteen patients with advanced hepatocellular carcinoma (HCC) received ADP-A2AFP in Cohort 3 and expansion
• The best overall responses in Cohort 3 and expansion (per RECIST v1.1) included 1 complete response (reported in 2020), 6 stable disease and 4 progressive disease. 2 patients did not have scan results at the time of data cut-off
• The disease control rate for patients with at least one scan was 7/11 (64%) and 2 patients had stable disease lasting beyond 16 weeks
  

Safety

• ADP-A2AFP has an acceptable safety profile with no reports of significant T-cell related hepatotoxicity and no protocol-defined dose limiting toxicities
• Adverse events (AEs) reported in 2 or more patients and considered related to T-cell infusion included neutropenia, leukopenia, lymphopenia, pyrexia, anemia, cytokine release syndrome, febrile neutropenia, thrombocytopenia, aspartate aminotransferase increased, and alanine aminotransferase increased
• Two patients reported a total of 3 treatment-related serious AEs including cytokine release syndrome (Grade 1), infusion-related reaction (Grade 2), and febrile neutropenia (Grade 3)
  

Conclusions

• Antitumor activity, with one complete response, sustained decreases in serum AFP, and best overall response of stable disease observed in 6 patients, indicate that ADP-A2AFP is an active product in HCC
• ADP-A2AFP up to doses of 10 billion transduced cells has been associated with an acceptable safety profile

Overview of Trial Design

• This is a Phase 1, open-label, dose escalation clinical trial designed to evaluate the safety and anti-tumor activity of ADP-A2AFP in patients with liver cancer (hepatocellular carcinoma) or other AFP-expressing tumors, who are not amenable to transplant, resection, or loco-regional therapy, and who failed or were intolerant to or refused standard-of-care treatment
• Dose escalation is complete, and this trial is intended to treat up to 25 patients with doses up to 10 billion transduced cells in the expansion phase

About Adaptimmune
Adaptimmune is a clinical-stage biopharmaceutical company focused on the development of novel cancer immunotherapy products for people with cancer. The Company’s unique SPEAR (Specific Peptide Enhanced Affinity Receptor) T-cell platform enables the engineering of T-cells to target and destroy cancer across multiple solid tumors. 

Forward-Looking Statements
This release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 (PSLRA). These forward-looking statements involve certain risks and uncertainties. Such risks and uncertainties could cause our actual results to differ materially from those indicated by such forward-looking statements, and include, without limitation: the success, cost and timing of our product development activities and clinical trials and our ability to successfully advance our TCR therapeutic candidates through the regulatory and commercialization processes. For a further description of the risks and uncertainties that could cause our actual results to differ materially from those expressed in these forward-looking statements, as well as risks relating to our business in general, we refer you to our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) on August 9, 2021 and our other SEC filings. The forward-looking statements contained in this press release speak only as of the date the statements were made and we do not undertake any obligation to update such forward-looking statements to reflect subsequent events or circumstances.

Adaptimmune Contacts:

Media Relations:

Sébastien Desprez — VP, Corporate Affairs and Communications
T: +44 1235 430 583
M: +44 7718 453 176
Sebastien.Desprez@adaptimmune.com

Investor Relations:

Juli P. Miller, Ph.D. — VP, Investor Relations
T: +1 215 825 9310
M: +1 215 460 8920
Juli.Miller@adaptimmune.com

Released September 5, 2021