Biotherapy Med International Anti-Cancer Immunotherapy

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

What is cancer immunotherapy? It is a form of cancer treatment that activates the patient’s own immune system to recognize and destroy malignant cells. At Biotherapy International, anti-cancer immunotherapy is used primarily for advanced cancer, recurrent cancer, and tumors resistant to standard treatment — either as a stand-alone therapy or in combination with surgery, chemotherapy, and radiation therapy. Our personalized cancer immunotherapy protocols are developed under the scientific direction of Professor Shimon Slavin.

How cancer immunotherapy differs from standard treatment

Cancer immunotherapy is a cancer treatment approach in which the patient’s own immune system is engaged in fighting the tumor. Unlike chemotherapy and radiation therapy, which act on cancer cells directly, immunotherapy treatment for cancer works indirectly: it helps the immune system “see” malignant cells and destroy them.

Modern cancer immunotherapy includes several directions: immune checkpoint inhibitors, monoclonal antibodies, anti-cancer vaccines, oncolytic viruses, infusions of activated donor killer cells, and cytokine therapy. At Biotherapy International, these directions are not applied in isolation but as part of personalized combination protocols.

When standard cancer treatment is no longer effective

In many cases, conventional cancer treatment such as surgery, chemotherapy, and radiation therapy can temporarily control the disease. However, a significant number of patients eventually face one of the following situations:

the tumor becomes resistant to treatment
the disease returns after an initial response
only a small number of cancer cells remain, continuing to drive recurrence
further chemotherapy is no longer effective or cannot be tolerated

In these situations, continuing the same treatment approach rarely leads to a different outcome.

This is where personalized cancer immunotherapy becomes especially relevant. Instead of directly targeting cancer cells with cytotoxic drugs, immunotherapy activates the patient’s immune system to recognize and eliminate remaining malignant cells, including those resistant to standard treatment.

At Biotherapy International, immunotherapy is most often considered precisely at this stage: when conventional options are exhausted or insufficient, but there is still a therapeutic window to influence the disease.

Who is immunotherapy recommended for

Personalized cancer immunotherapy may be recommended in the following situations:

metastatic cancer or stage IV disease
recurrent cancer after surgery or chemotherapy
tumors that no longer respond to standard treatment
inability to continue chemotherapy due to toxicity

In these cases, immunotherapy is not used as a general alternative, but as a targeted strategy designed based on the biology of the tumor and the patient’s immune status.

Each case is evaluated individually. The goal is not simply to apply immunotherapy, but to select the right combination of methods at the right stage of the disease.

How cancer immunotherapy works

The role of the immune system is to recognize foreign agents, including cancer cells, and destroy them. It is widely accepted that most malignant tumors originate from a single mutated cell and its descendants. This explains why durable long-term remission typically requires eliminating or maintaining immune control over every remaining malignant cell. Unfortunately, conventional methods are not always able to accomplish this task.

Anti-cancer immunotherapy — that is, activating the immune system to recognize and destroy cancer cells more effectively, is one of the most promising directions in modern oncology. The failure of the immune system to handle cancer arises from several mechanisms that actively suppress its response.

Cancer immunotherapy should include three main directions:

Eliminating all factors that suppress the activity of the immune system.
Activating the body’s natural anti-tumor mechanisms.
Using drugs with scientifically proven anti-cancer efficacy to enhance the therapeutic potential of immunotherapy.

Cancer immunotherapy can be compared to a real battle. If the number of “soldiers” (immune cells) exceeds the number of “enemies” (cancer cells), or if your soldiers are better trained and better equipped, the chance of victory increases. Conversely, if malignant cells multiply faster than immune cells and their killing capacity is higher, it becomes difficult for the body to win this fight.

Cancer immunotherapy treatment gives the immune system the ability to identify and destroy cancer cells. For example, activated donor killer cells introduced into the patient can eliminate cancer cells that do not respond to standard treatment, even in malignancies resistant to standard treatment. This is why immunotherapy plays a particularly important role when applied after conventional treatment has reduced the disease to minimal residual disease (MRD), the point at which the smallest number of cancer cells remains.

Why the immune system fails to “see” the tumor: three mechanisms

The reduced activity of a patient’s lymphocytes, which compromises natural defenses against cancer, can result from a combination of three factors:

Weak immunogenicity of cancer antigens. The antigens that distinguish cancer cells from healthy ones have low immunogenicity, meaning they trigger only a weak immune response.
Active immunosuppression. In cancer, levels of cells that block the anti-tumor activity of the immune system rise (regulatory T cells, myeloid-derived suppressors, and others).
Immunological tolerance. The immune system develops unresponsiveness or tolerance to malignant cells, which mimic “healthy” cells, so the immune system no longer perceives them as foreign.

For cancer immunotherapy treatment to succeed, a comprehensive approach that addresses all three factors simultaneously is required.

Key immunotherapy approaches used at Biotherapy International

At Biotherapy International, treatment is based on a structured, multi-step approach that combines several complementary methods used in a specific sequence. Many of these strategies are based on proprietary developments by Professor Shimon Slavin and years of clinical experience in treating advanced and treatment-resistant cancers.

Below are the main components used in personalized protocols:

Oncolytic viruses
Oncolytic viruses selectively infect tumor cells and replicate predominantly within them. As a result, cancer cells are destroyed, and the released tumor antigens become more visible to the immune system. At the same time, the viral infection creates a local inflammatory signal within the tumor microenvironment, helping to recruit and activate immune cells against the cancer.

Anti-cancer vaccines (personalized tumor vaccines)
Cancer vaccines are developed individually using the patient’s own tumor material. Tumor samples are processed and modified to increase their immunogenicity, enabling the immune system to recognize cancer cells more effectively. This helps generate a targeted immune response, allowing the body to detect and destroy tumor cells, including those that previously evaded immune surveillance.

ATACK (Allogeneic Targeted Activated Cancer Killer cells)
ATACK is a proprietary method developed by Professor Shimon Slavin. It uses intentionally mismatched donor immune cells (T cells, NK cells, NKT cells), which are activated and directed against tumor cells. To enhance targeting, monoclonal antibodies are used to bind specific antigens overexpressed on cancer cells, marking them as “non-self.” This triggers a powerful immune reaction, helping eliminate cancer cells that do not respond to standard treatment.

Full list of immunotherapy methods at the clinic →

In contrast to standard oncology protocols, these methods are not used in isolation. Their effectiveness depends on proper sequencing and combination, tailored to the patient’s condition, tumor biology, and stage of disease.

The goal of treatment is not simply to apply immunotherapy, but to simultaneously:

increase tumor visibility to the immune system
overcome mechanisms of immune suppression
activate and direct immune cells
eliminate resistant cancer cell populations

Which cancers we treat with immunotherapy

At Biotherapy International, anti-cancer immunotherapy is applied to a wide range of oncological conditions — particularly those for which standard treatment has exhausted its options or shown limited effectiveness, including metastatic and recurrent cancer:

All cancer types we treat →

How a personalized immunotherapy protocol is designed

At Biotherapy International, treatment is not based on a fixed protocol. Instead, each patient undergoes an individual assessment that determines the treatment strategy.

The protocol is built step by step:

Clinical evaluation
The type of cancer, stage, tumor biology, prior treatments, and current disease burden are analyzed.
Identification of the therapeutic window
Whenever possible, treatment is aligned with the minimal residual disease (MRD) stage when the number of cancer cells is lowest and immunotherapy is most effective.
Increasing tumor visibility (oncolytic virus therapy)
Treatment often begins with oncolytic viruses, which directly destroy cancer cells and increase their visibility to the immune system, making subsequent immune-based therapies more effective.
Activation of anti-tumor immunity and overcoming immune resistance
At the next stage, immune checkpoint inhibitors or cytokine-mediated immunotherapy (CMI) may be introduced. These approaches enhance the immune response and help overcome tumor-induced immune suppression. Sequential use is important, as early immune activation may reduce the effectiveness of viral therapy.
Targeted elimination of residual and resistant cancer cells
When disease burden is reduced, especially at the MRD stage, advanced methods such as ATACK therapy (activated donor immune cells) are used to eliminate remaining resistant cancer cells.
Combination strategy
Rather than relying on a single method, multiple approaches are combined in a coordinated sequence to target different survival mechanisms of the tumor.

This multi-step approach is the key difference between personalized immunotherapy and standard treatment protocols.

“Cancer is not only treatable — when the principles of optimal immunotherapy are consistently applied, durable long-term remission becomes a realistic goal. Even at advanced stages, properly chosen therapy can slow the disease and preserve the patient’s quality of life.” — Professor Shimon Slavin, Founder and Scientific Director of Biotherapy International.

Patient stories and video testimonials

Real clinical cases and video interviews with our patients:

Contact us

If you or your loved one are considering immunotherapy as a treatment option, the Biotherapy International team is ready to review your medical records and propose a personalized treatment plan.

FAQ

When chemotherapy stops working, can immunotherapy help?

Yes. Resistance to chemotherapy develops when cancer cells acquire mutations that allow them to survive cytotoxic drugs. Immunotherapy works through a fundamentally different mechanism, it activates the immune system to recognize tumor cells regardless of their drug-resistance profile. This is why immunotherapy can be effective specifically in cases where chemotherapy no longer works.

Is immunotherapy used as a last-line treatment?

Immunotherapy is often used when standard treatments such as chemotherapy or radiation are no longer effective or are not well tolerated. However, in personalized treatment approaches, it may also be introduced earlier, especially in combination with other therapies or when the tumor burden is lower.

Can immunotherapy help with stage 4 cancer?

Immunotherapy may be considered in stage 4 or metastatic cancer, particularly when standard treatment options are limited. In such cases, treatment goals may include slowing disease progression and maintaining quality of life. Suitability depends on the individual clinical situation.

Can cancer immunotherapy lead to remission?

In some cases, immunotherapy can lead to long-term disease control or remission. Outcomes depend on multiple factors, including tumor type, stage, and prior treatment. Treatment strategy and expectations are always discussed individually after reviewing medical records.

Can immunotherapy be combined with chemotherapy?

Yes, in some cases immunotherapy may be combined with chemotherapy. For example, in brain tumors, these approaches can be used in parallel depending on the treatment plan. In other cases, immunotherapy is more often considered after chemotherapy, especially when the tumor burden has been reduced.

Can immunotherapy be combined with radiation therapy?

Yes, in selected cases immunotherapy may be used alongside radiation therapy or shortly after it. Radiation can increase tumor antigen release and enhance immune recognition. In brain tumors, it may also temporarily increase the permeability of the blood–brain barrier, which can support treatment delivery.

How is immunotherapy administered?

Most immunotherapy treatments are administered intravenously. In selected cases, intratumoral delivery may be used to increase local effectiveness. For brain tumors, treatment can also be delivered directly into the tumor area using an Ommaya reservoir, allowing higher local concentrations with reduced systemic exposure.

What are the side effects of immunotherapy?

Immunotherapy is generally better tolerated than traditional cancer treatments. Most side effects are mild and may include fatigue, chills, or a temporary increase in body temperature after treatment. More serious immune-related reactions are rare, and patients are monitored throughout treatment to identify and manage any side effects early.

When is immunotherapy not recommended?

Immunotherapy may not be appropriate in some clinical situations, for example in patients with significantly reduced overall condition. Each case is evaluated individually based on the patient’s condition, tumor characteristics, and prior treatment history.

Do you accept international patients?

Yes. Biotherapy International works with patients from around the world, including the United States, the United Kingdom, and other countries. Consultations with Professor Slavin are conducted online via Zoom, after which a personalized treatment protocol is developed based on the patient’s medical records. The Biotherapy International team also assists with organizational aspects and supports patients throughout all stages of treatment.

What medical records should I send for the initial review?

For an initial assessment, we typically request recent imaging studies (CT, MRI, PET-CT), pathology and biopsy reports, a summary of prior treatments (chemotherapy, radiation, surgery), and current laboratory results.

How long does immunotherapy treatment take?

Treatment duration varies depending on the protocol and the patient's response. Initial active treatment typically requires about 2 weeks at the clinic, followed by maintenance phases that may continue on an outpatient basis. Specific timelines are defined in the personalized treatment plan after medical record review.

How is the cost of immunotherapy determined?

Pricing depends on the type of cancer, stage of disease, and the specific combination of methods used in the protocol. Exact pricing is provided after the initial review of medical records.