AstraZeneca PLC (LSE:AZN) said its biologics license application for tremelimumab, an anti-CTLA4 antibody, has been accepted for Priority Review in the US for patients with unresectable liver cancer in combination with Imfinzi (durvalumab).
This novel dose and schedule of the combination is called the STRIDE regimen (Single Tremelimumab Regular Interval Durvalumab), AstraZeneca said in a statement.
The combination involves adding a single priming dose of tremelimumab to Imfinzi for the treatment of patients with unresectable hepatocellular carcinoma (HCC). A supplemental application has also been submitted for Imfinzi in this indication.
This is the first dual immune checkpoint blockade regimen to improve overall survival in a phase III trial in this setting.
The regulatory decision by the US Food and Drug Administration (FDA) is expected in the fourth quarter of 2022 following the use of a priority review voucher, the pharmaceutical company said.
Liver cancer, of which HCC is the most common type, is the third-leading cause of cancer death and the sixth most commonly diagnosed cancer worldwide.
The BLA for tremelimumab and sBLA for Imfinzi are based on final results from the HIMALAYA Phase III trial, which demonstrated that patients treated with the STRIDE regimen experienced a 22% reduction in the risk of death versus sorafenib. Nearly one in three patients were still alive at three years versus one in five for sorafenib.
Susan Galbraith, executive vice president, Oncology R&D, AstraZeneca, said: "The HIMALAYA Phase III trial showed an unprecedented three-year overall survival in this setting with a single priming dose of tremelimumab added to Imfinzi, highlighting the potential for this regimen to improve longer-term survival outcomes.
“Patients with advanced liver cancer are in great need of new treatment options, and we are working closely with the FDA to bring this novel approach to patients in the US as soon as possible."
Imfinzi and tremelimumab were granted Orphan Drug Designation in the US for the treatment of HCC in January 2020.
As part of its extensive clinical development programme in gastrointestinal (GI) cancers, AstraZeneca is further assessing Imfinzi across multiple liver cancer settings, including locoregional HCC and adjuvant HCC.