FDA Grants Fast Track Designation to BST02 for Liver Cancer

The FDA has granted a fast track designation to the T-cell therapy BST02 for the treatment of patients with all forms of liver cancer, including hepatocellular carcinoma (HCC) and cholangiocarcinoma.¹

BST02 is a novel adoptive immune cell therapy that depends on the expansion of tumor-infiltrating lymphocytes (TILs) derived from a patient’s cells. Notably, BST02 does not require high doses of interleukin-2 and is cryopreserved, overcoming distance constraints with traditional TIL therapies.²

In October 2023, the FDA granted an investigational new drug approval to BST02 for evaluation in a phase 1/2 clinical trial, representing the first TIL cell therapy to advance to the clinical stage globally. The agent also received approval from the China National Drug Administration in January 2024.^1,2

BSTO2 is being evaluated in an open-label, single-arm, investigator-initiated phase 1 trial (NCT06173726).³ To be eligible for enrollment, patients have to be between the ages of 18 and 75 years and have histologically or cytologically confirmed locally advanced or metastatic liver cancer including HCC, intrahepatic bile duct carcinoma, and metastatic liver cancer. HCC and cholangiocarcinoma must be stage B or C and not amenable to local treatment, and those with metastatic liver cancer should not be eligible for radical surgery.

Patients with locally advanced liver cancer should have received frontline systemic therapy at minimum or be deemed unsuitable for or refused such treatment after failure of prior therapy. Patients with metastatic disease must have experienced disease progression or intolerance on second- or later-line therapy, refused standard therapy, or received an inappropriate treatment recommendation according to the investigator.

Patients also have to be fit enough to undergo at least one operation without radiation or other local treatment within 28 days to remove the tumor lesions with an estimated lesion volume of at least 8 cm3, excluding necrotic areas, for the preparation of BST02 cells.

Additional eligibility criteria require at least one measurable lesion per RECIST v1.1 criteria, an ECOG performance status of 0 or 1, Child-Pugh score of cirrhosis of 7 or fewer points, at least 3 months of expected survival time, and adequate organ and bone marrow function during the screening period or within 14 days prior to TIL sampling. Any adverse effect (AE) related to prior therapy––adjudicated by the investigator to have no safety risk––must have resolved to grade 1 or lower prior to tumor sampling according to the Common Adverse Event Evaluation Criteria.

Patients received 250 mg or 1.5 g/m2 of a single intravenous infusion of cyclophosphamide 3 days before receiving an infusion of BST02 to stimulate lymphocyte proliferation.

The primary objectives of the study are the occurrence and incidence of AEs, severe AEs, and dose-limiting toxicity.

The study’s primary completion date is December 5, 2026.

References

1. Biosyngen announces FDA fast track designation for BST02 in treatment of liver cancer. News release. Biosyngen. February 1, 2024. Accessed February 1, 2024. https://www.prnewswire.com/news-releases/biosyngen-announces-fda-fast-track-designation-for-bst02-in-treatment-of-liver-cancer-302050377.html
2. Biosyngen’s BST02, the world’s first TIL therapy for liver cancer, is granted an IND approval by FDA. News release. Biosyngen. October 26, 2023. Accessed February 1, 2024. https://www.prnewswire.com/news-releases/biosyngens-bst02-the-worlds-first-til-therapy-for-liver-cancer-is-granted-an-ind-approval-by-fda-301968656.html
3. Investigator-initiated phase I exploratory clinical study of the safety, tolerability, and efficacy of BST-2 injection in the treatment of locally advanced/metastatic liver cancer. ClinicalTrials.gov. Updated December 18, 2023. Accessed February 1, 2024. https://classic.clinicaltrials.gov/ct2/show/NCT06173726