Clinical-stage biotechnology company SystImmune Inc and pharmaceutical company Bristol Myers Squibb (BMS) (NYSE:BMY) announced on Monday that the US Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) to izalontamab brengitecan (iza-bren) for the treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC) with epidermal growth factor (EGFR) exon 19 deletions or exon 21 L858R substitution mutations whose disease has progressed on or after treatment with an EGFR tyrosine kinase inhibitor (TKI) and platinum-based chemotherapy.

Iza-bren is a potential first-in-class bispecific antibody-drug conjugate (ADC) which targets both epidermal growth factor receptor and human epidermal growth factor receptor 3 (EGFRxHER3) with a topoisomerase 1 inhibitor payload. Iza-bren is being developed by Biokin in China and jointly developed by SystImmune and Bristol Myers Squibb under a collaboration and exclusive licence agreement in territories outside of China.

BTD from the US FDA is intended to expedite the development and review of drugs that may demonstrate significant benefit over current standards of care.

The FDA's decision was based on efficacy and safety data from three ongoing clinical trials: BL-B01D1-101 and BL-B01D1-203, conducted in China by Sichuan Biokin Pharmaceutical Co Ltd, and the global BL-B01D1-LUNG-101 study conducted by SystImmune across the United States, Europe and Japan. Across these trials, the companies say that iza-bren demonstrated evidence to suggest improved efficacy with a manageable safety profile in patients with EGFR-mutant NSCLC who had progressed after third-generation EGFR TKIs and platinum-based chemotherapy.