AbClon is making a move to dominate the untapped solid tumor CAR-T market, having completed its global patent portfolio, including in the U.S.

On the 17th, antibody drug development company AbClon announced that it has received a patent grant decision from the U.S. Patent and Trademark Office (USPTO) for its 'HER2 Affibody-based Switchable CAR-T Technology.'

With this, AbClon has secured exclusive technological rights in the world's largest pharmaceutical market, the U.S., following Korea, Canada, China, Japan, and Australia, with final registration also pending in Europe.

The newly patented technology is a 'Switchable' CAR-T, designed to activate immune cells targeting HER2-expressing cancer cells only when needed. This next-generation platform addresses the fundamental limitations of existing CAR-T therapies.

Currently, all seven FDA-approved CAR-T products are limited to blood cancers. Their T-cell receptors, which recognize cancer cells, are permanently bound, resulting in an 'always-on' state once injected into the body, where they are continuously active.

This can lead to severe side effects such as Cytokine Release Syndrome (CRS) and Immune effector Cell-Associated Neurotoxicity Syndrome (ICANS), and even attacks on healthy cells. Furthermore, because they only target a single antigen, their therapeutic effect diminishes if cancer cells develop resistance.

AbClon 's proprietary switchable CAR-T platform, 'zCAR-T,' is designed to require an intermediary 'switch molecule' instead of the CAR-T cells directly recognizing cancer cells. Much like an electrical switch, it allows the CAR-T cells to be turned on and off as needed.

AbClon has utilized the zCAR-T platform to develop its HER2 affibody-based switchable CAR-T technology, which is the core technology for its first zCAR-T candidate, 'AT501,' currently in preclinical development as a treatment for ovarian cancer.

AT501's switch molecule consists of two parts. One side, 'cotinine' (a metabolite of nicotine), binds to the CAR-T cell, while the other side, an 'affibody' (a small protein about 1/25th the size of a regular antibody), binds to cancer cells that express HER2.

This acts like a bridge between the cancer cell and the CAR-T cell. The switch molecule can be used to control the activation and proliferation of CAR-T cells and to change and regulate their targets. Additionally, if side effects occur, administration of the switch molecule can be stopped to immediately halt the CAR-T cell activity.

The HER2 targeted therapy market was valued at $8.9 billion in 2021 and is growing at an annual rate of 12%. Blockbuster drugs like Herceptin, Perjeta, and Enhertu form a market worth over $12 billion annually. However, most of these are based on monoclonal antibodies or ADCs, and a CAR-T approach is still in its early stages.

While several pharmaceutical companies like CARsgen and Adaptimmune Therapeutics are developing solid tumor CAR-T therapies, few possess a specialized switchable platform for HER2, which is drawing market attention to AbClon's differentiated technology.

An AbClon official stated, "The U.S. patent registration for our 'HER2 Affibody-based Switchable CAR-T Technology' will be a major catalyst for us to lead the charge in the untapped solid tumor CAR-T market. We have confirmed the potential for our switchable CAR-T platform, 'zCAR-T,' to expand beyond a single therapeutic agent into a platform-based business model, so we will be accelerating licensing agreements and joint development collaborations with multinational pharmaceutical companies."

Furthermore, while conventional CAR-T therapies are developed to directly target specific proteins on the surface of cancer cells, requiring a separate CAR-T for each cancer type, AbClon's zCAR-T platform allows for a single 'switchable CAR-T' to be created, with different switch molecules developed for each cancer type.

For example, a HER2-targeting switch can be used for HER2-positive breast cancer, and a different target switch can be used for ovarian cancer. Moreover, using multiple switch molecules simultaneously allows for multi-target attacks, which can overcome issues of immune evasion and resistance due to antigen loss in cancer cells.