Allogeneic Targeted Activated Cancer Killer cells (ATACK)

Medically reviewed by Prof. Shimon Slavin, MD. Updated: June 2026

In many cancers, the patient’s own immune cells cannot recognise or effectively attack tumour cells. Cancer cells develop ways to hide from the immune system or suppress it, making conventional immunotherapy only partially effective in some patients.

ATACK is designed for situations where the patient’s own immune response has not been sufficient. Instead of trying to re-activate an immune system that cancer has already learned to evade, ATACK introduces pre-activated killer cells from a healthy donor that are not subject to the same tolerance and can attack cancer cells more effectively.

How Does ATACK Work?

ATACK uses intentionally mismatched donor cells, including T cells, NK cells, and NKT cells, which are activated and targeted against the patient’s cancer cells before infusion.

Because these mismatched killer cells come from a different individual, cancer cells cannot evade them in the same way they evade the patient’s own immune system. The donor cells recognise the cancer as foreign and attack it through a powerful rejection-like mechanism, based on the same biological principle involved in the rejection of foreign tissue.

To further focus this attack, monoclonal antibodies are used against specific antigens overexpressed on the surface of the cancer cells. After infusion, the donor cells can be further stimulated by IL-2, and this process also activates the patient’s own T cells and NK cells to join the response.

Who Is ATACK For?

ATACK is a form of allogeneic cell therapy considered for patients with advanced or recurrent cancer where standard therapies have not achieved sufficient control of the disease.

It is particularly relevant when tumour burden has been reduced to a minimum, a stage known as minimal residual disease (MRD), because this is when targeted cell therapy can be most effective against remaining resistant cells, including cancer stem cells.

ATACK may be recommended as part of a broader treatment programme, in combination with other approaches such as oncolytic virus therapy or other immunotherapy modalities, rather than as a standalone treatment.

Why Choose ATACK?

A patient’s own lymphocytes often cannot mount an effective attack against cancer cells, and when stimulated, their anti-cancer response is limited. This is the fundamental challenge with conventional immunotherapy approaches.

The advantage of ATACK is that intentionally mismatched donor cells are not subject to the same immune tolerance. They are more effective at inducing the rejection of cancer cells because they come from outside the patient’s body. In most cases, a healthy donor can serve as a suitable donor for ATACK without the need for tissue typing.

Where Can a Patient Get ATACK Treatment?

ATACK requires donor lymphocytes to be collected, activated, and expanded outside the body before infusion. This procedure is administered at Biotherapy International’s partner clinics abroad, including our partner clinic in Germany.

Our medical coordinators handle the logistics of referral and treatment planning for international patients.