A2 Biotherapeutics (A2 Bio) has received the US Food and Drug Administration's (FDA) orphan drug designation for its cell therapy, A2B530, to treat colorectal cancer.

The designation is a significant milestone for A2B530, the first autologous logic-gated therapy developed from A2 Bio's Tmod platform.

The cell therapy is aimed at treating germline heterozygous HLA-A*02(+) patients who express carcinoembryonic antigen (CEA) and have lost HLA-A*02 expression.

The Tmod platform's dual-receptor design, comprising an activator that targets tumour cells and a blocker for normal cells, addresses the issue with other solid tumour cancer treatments. It acts by selectively targeting tumour cells while sparing healthy ones.

A2B530 deploys an activator for CEA and a blocker for HLA-A*02, potentially offering a more precise cancer treatment approach.

Orphan drug status brings development incentives for A2 Bio, including tax credits for clinical trial costs, prescription drug user fee exemptions and the possibility of up to seven years of market exclusivity upon regulatory approval.

In May 2023, the company dosed the first subject in the Phase I clinical trial of A2B530.

The multicentre Phase I dose escalation trial EVEREST-1 enrolled patients with colorectal, pancreatic and non-small cell lung cancers to assess safety and establish the recommended dose for A2B530.

A2 Bio chief medical officer William Go stated: “The FDA granting orphan drug designation validates the tremendous unmet need for improved therapies for patients with colorectal cancer.

“This designation supports our commitment to use our novel technology platform to develop new treatment options for patients with difficult-to-treat cancers.”

In December 2020, the company signed an agreement with MSD to continue research and preclinical development of its undisclosed Tmod cell therapy candidate.

The companies jointly financed the clinical development and allogeneic manufacturing works of the product until the start of the Phase I clinical trial.