EASL Wrap-up Session Highlighted Late-Breaking Clinical Data of First-in-class HBV-specific TCR T Cell Therapy (SCG101) Showing Improved Overall Survival in HBV-related Hepatocellular Carcinoma

SINGAPORE, June 7, 2024 /PRNewswire/ -- SCG Cell Therapy Pte Ltd (SCG), a clinical-stage biotechnology company developing novel immunotherapies for infectious diseases and their associated cancers, announced that clinical data from its first-in-class autologous hepatitis B virus (HBV)-specific T-cell receptor-engineered T Cell (TCR T) therapy – SCG101 – was featured in a late-breaking session during the European Association for the Study of the Liver (EASL) Congress 2024 in Milan, Italy. The presentation was selected for inclusion in the Best of EASL Congress Wrap-Up summary, distilling the best, the most memorable highlights, the future trends and the most noteworthy contributions to the program at EASL.

Results from the first-in-human clinical trial showed that SCG101 exhibited promising antiviral and antitumor dual activities in patients with advanced HBV-related hepatocellular carcinoma (HCC). In six patients with advanced HBV-HCC who received SCG101 at 5.0×10⁷ ~ 1.0×10⁸ TCR+ T cells/kg, the objective response rate (ORR) is 33%. All patients who achieved partial responses (PR) maintained remission for over 6 months, and one had complete remission of the target lesion and remained progression-free for 27 months.

The tumor responses were highly correlated with the antiviral activities of SCG101. As of the data cutoff, 4 out of 6 patients (67%) achieved serum HBsAg reduction of 1~4 log₁₀ after single SCG101 infusion. The HBsAg level maintained ≤15 IU/mL throughout the follow up period for up to 27 months. Tumor reduction was observed in all patients with serum HBsAg reduction ≥1 log₁₀, and the median progression free survival (PFS) and overall survival (OS) were prolonged (mPFS: 5.9 vs 0.7 months, mOS:19.0 vs 6.3 months) in patients with HBsAg reduction ≥1 log than in those without.

The safety analysis revealed that SCG101 was generally well tolerated with no cases of serious adverse events (SAE) or immune effector cell-associated neurotoxicity syndrome (ICANS). The most common SCG101-related adverse events were transient liver enzymes evaluation, cytokine release syndrome (CRS) and fever, which were expected due to SCG101's mechanism of clearance of HBsAg-expressing cells.

HBV infection is a leading cause of liver cancer and accounts for 50%-80% of HCC cases worldwide.^[1] HBV DNA integrates into the host genome and leads to genetic instability of the host cell and epigenetic remodelling of host DNA, resulting in abnormal expression of oncogenes and HBV antigens.^[2] SCG101 can specifically target an HBV peptide presented on HBV-HCC tumor cells, HBV-DNA integrated premalignant hepatocytes, and HBV-infected cells, triggering cytolytic and non-cytolytic mechanisms to eliminate tumor cells and HBV-infected cells.

"We are excited that our late-breaking data was featured at the EASL Wrap-up session, presenting compelling dual antiviral and antitumor profile of SCG101 with sustained HBsAg reduction and prolonged progression-free survival and overall survival in patients with HBV-HCC," said Christy Ma, Chief Executive Officer of SCG Cell Therapy. "These data highlight the strength of our GianTCR^TM platform to generate promising TCR-based therapeutic candidates across a broad range of therapeutic areas and, in particular, for the treatment of infectious diseases and its associated cancer. We look forward to further investigating SCG101 as well as other TCR candidates, bringing positive impact to patients with unmet needs."

About SCG101
SCG101, an autologous T-cell receptor (TCR) T cell therapy, is an investigational cell therapy product targeting a specific epitope of hepatitis B surface antigen (HBsAg). Utilizing SCG's proprietary GianT^TM technology, high affinity and high avidity natural TCRs can be identified against intracellular antigens presented through major histocompatibility complex (MHC) in solid tumours. Preclinical and clinical studies of SCG101 demonstrated tumour inhibition and HBV cccDNA eradication. SCG101 was granted clinical trial approvals by the U.S Food and Drug Administration (FDA), China National Medical Products Administration (NMPA) and Singapore Health Science Authority (HSA) and Hong Kong Department of Health (DOH) for patients with HBV-related HCC. A Phase 1/2 clinical trial evaluating SCG101 is ongoing (NCT05417932).

About Hepatocellular carcinoma
Hepatocellular carcinoma (HCC) is the most common type of liver cancer. It is estimated that more than 905,000 new cases of liver cancer and more than 830,100 deaths from the disease globally in 2020, making it one of the leading causes of cancer deaths around the world.^[3] Chronic HBV infection accounts for at least 50% of cases of HCC worldwide.^[1] HCC is typically diagnosed at an advanced stage and is associated with a poor prognosis. The five-year survival rate of less than 15%.^[4]  

About SCG Cell Therapy
SCG is a leading biotechnology company focusing on the development of novel immunotherapies in infections and its associated cancers. The company targets the most common cancer-causing infections: helicobacter pylori, HPV, HBV and EBV, and develops a broad and unique pipeline of TCR-based cellular immunotherapy products against infection- associated cancers. With the proprietary GianTCR^TM TCR screening platform, in-house viral vector production and AutoCell^TM, a fully closed and automatic cell therapy manufacturing system, the company covers the entire value chain of cell therapy development from new target research and discovery, manufacturing, and clinical development. For more information about SCG, please visit us at www.scgcell.com.