Cancer Immunotherapy Month 2026: Reach, science, and clinical trials

Cancer immunotherapy is a class of cancer therapies that work by activating the patient's own immune system to find and attack cancer cells, rather than attacking the cancer directly with chemotherapy or radiation. Fifteen years ago, immunotherapy was used in only a few cancers and was considered experimental for most. By 2026, it is part of standard care for more than a dozen adult cancers, including advanced melanoma, several lung cancers, kidney cancer, head and neck cancers, bladder cancer, and certain blood cancers, with a growing list under active study. Each June, Cancer Immunotherapy Month draws attention to the reach of this field, the science behind it, and the cancer immunotherapy clinical trials that continue to expand both.

What Cancer Immunotherapy Month is about

Cancer Immunotherapy Month is observed every June in the United States and is recognized in several other countries. The observance is anchored by two US-based organizations: a national professional society for cancer immunotherapy clinicians and researchers, based in Milwaukee, which holds the trademark for the month, and a research foundation based in New York that funds early-stage immunotherapy science and supports patients navigating immunotherapy care. The 2026 framing centers on honoring the patients, caregivers, researchers, and clinicians whose work has changed what cancer care can look like.

The month exists because cancer immunotherapy is one of the larger care-landscape shifts in recent medical history, but it is also one that many people outside oncology still do not understand well. Awareness efforts during June focus on what immunotherapy is, what it can and cannot do, which cancers it currently works for, and how the next wave of research is being designed.

For a wider view of how clinical research connects to broader public health, How Clinical Trials Contribute to Public Health describes the framework that cancer immunotherapy progress fits inside.

The reach: which cancers immunotherapy has changed

Until roughly 2010, most cancers were treated with surgery, radiation, chemotherapy, and a smaller set of targeted therapies. Outcomes for several advanced cancers were poor. Between 2011 and the early 2020s, a class of immunotherapies called immune checkpoint inhibitors reshaped what was possible in advanced melanoma, the most common kind of lung cancer (non-small-cell lung cancer), kidney cancer, certain head and neck cancers, bladder cancer, several blood cancers, and a number of others. For some of these cancers, a fraction of patients who would not previously have lived more than a few months are now in long-term remission years later.

The reach has expanded across stages of disease too. Early uses of immunotherapy focused on advanced or metastatic cancers, where standard options had run out. Today, immunotherapy is increasingly given before surgery to shrink a tumor and prime the immune system (called neoadjuvant therapy), or after surgery to reduce the risk of recurrence (called adjuvant therapy). CAR T-cell therapy, a different kind of immunotherapy that engineers a patient's own immune cells in a laboratory and returns them to the body, is now approved for several blood cancers and is being studied in solid tumors as well.

For a snapshot of cancer-specific research moving forward right now, 5 Active Clinical Trials Advancing Cancer Care covers studies across the wider oncology research landscape.

The science: how immunotherapy works

The body's immune system is built to find and destroy cells that look wrong, including damaged or infected cells. Cancer cells often look wrong, but they also have ways to hide from the immune system or shut it down. Cancer immunotherapy is the work of designing therapies that either remove the cancer's hiding strategies or give the immune system sharper tools to recognize and respond.

Most current cancer immunotherapies fall into five broad categories. Checkpoint inhibitors release the natural brakes that keep the immune system from over-reacting; cancer cells exploit those brakes to avoid attack, and these drugs close that loophole. Cell therapies, of which CAR T is the most well-known, take a patient's own immune cells out of the body, engineer them in a laboratory to better recognize the cancer, and put them back in. Monoclonal antibodies are lab-made versions of the immune system's own targeting proteins, designed to grab a specific marker on a cancer cell. Cancer vaccines train the immune system to recognize features unique to a patient's tumor. Cytokines and other immune-stimulating agents amplify the immune response more broadly.

Newer approaches add to this list. Bispecific T-cell engagers physically link an immune cell to a cancer cell, forcing the immune cell to recognize and attack the tumor. Oncolytic viruses are engineered viruses that infect and kill cancer cells while alerting the immune system to attack what is left behind.

For a plain-language overview of how clinical trials are designed and what they are for, Clinical Trials Explained: Simple Guide for Beginners covers the basics.

What immunotherapy can and cannot do

Immunotherapy does not work the same way for every cancer or every patient. Response rates vary widely. Some cancers, often called "hot" tumors, have a lot of immune activity already happening around them, and immunotherapy works well for many of these patients. Other cancers, called "cold" tumors, have little immune activity, and immunotherapy by itself often does not work for them. A great deal of current research is focused on turning cold tumors hot, on combining immunotherapy with other approaches such as chemotherapy or radiation, and on identifying which patients are most likely to respond to a given drug.

Side effects are also different from those of chemotherapy. Because immunotherapy activates the immune system, it can occasionally cause the immune system to attack healthy tissue. These are called immune-related adverse events. Most are mild, such as a rash, fatigue, or temporary thyroid changes. A small number can be more serious, affecting the lungs, gut, liver, or heart, and require prompt management by a team experienced with immunotherapy. This is one reason immunotherapy care is usually delivered at centers with the resources to recognize and manage these events early.

For a closer look at why eligibility criteria exist and how they shape who can join a trial, Eligibility Explained: Why Not Everyone Qualifies for a Trial walks through the reasoning.

Clinical trials in cancer immunotherapy today

Based on a search of public trial registries in June 2026, roughly 439 cancer immunotherapy clinical trials are actively recruiting participants in the United States, of which about 249 are in Phase 2 or Phase 3 (the stages that test how well an approach works rather than just whether it is safe to give). Lung cancer alone accounts for about 98 recruiting immunotherapy trials in the United States. For comparison, the broader field of all recruiting cancer studies in the United States runs to roughly 6,992 trials, placing immunotherapy at around one in every sixteen currently recruiting cancer studies. These counts shift as trials open and close, so the exact numbers will look different a few months from now.

Currently recruiting cancer immunotherapy trials fall into a few broad categories. Some are testing entirely new drugs or cell therapies that have not been approved yet. Some are testing approved immunotherapies in combination with each other or with chemotherapy, radiation, or surgery. Some are studying patients who did not respond to a first immunotherapy, looking for ways to make the second approach work. And some are observational, following large groups of patients over years to learn what predicts long-term response, how side effects evolve, and what factors raise or lower the risk of recurrence.

A few concerns come up often when patients and families start thinking about a cancer immunotherapy trial. One concern is that joining a study means receiving an unproven therapy instead of standard care. In most modern cancer immunotherapy trials, the design is built around standard of care, not against it; new approaches are usually tested in addition to, or in direct comparison with, an existing approved option, not by replacing care with nothing. Another concern is that clinical trials are only for patients who have run out of other options. In immunotherapy, research now reaches across the spectrum of disease, including studies in earlier stages and in patients who have not yet started a first line of therapy. A third concern is uncertainty about side effects. Every cancer immunotherapy trial follows a written plan, called a protocol (the document that defines how a study is run), and every participant goes through a careful consent conversation with the research team before agreeing to take part, including a review of the specific side effects to watch for.

DecenTrialz helps people in the United States find clinical trials that may fit their situation. After someone shares basic information about themselves and the conditions they are interested in, the platform may identify trial options that appear to match their profile. A registered nurse then completes an initial pre-screening review before the person is referred to the research site running the study. The research site and study team handle the walk-through of study details, the final eligibility check, the consent conversation, and enrollment, since they are the ones responsible for the participant's care during the trial. You can start a search at decentrialz.com.

For a step-by-step look at how the path from interest to enrollment usually unfolds, How to Find and Enroll in a Clinical Trial: A Step-by-Step Guide walks through what to expect.

What June asks of everyone touched by cancer

For patients and the people who love them, Cancer Immunotherapy Month is an invitation to ask questions: whether immunotherapy is an option for the cancer in front of you, whether a trial might widen what is on the table, and whether a second opinion at a center experienced with immunotherapy would help. The reach of the field has expanded faster than most people realize, and the question worth asking has shifted from "is immunotherapy possible for me" to "which immunotherapy approach, and at what stage."

For everyone else, the month is a reminder that cancer care has changed in a meaningful way in a short time, and that the change has come from research participation, slow and steady, study after study. Each patient enrolled in a trial moved the field one step closer to where it is today.

And for anyone exploring whether a current cancer immunotherapy study fits their situation, June is a good time to look at what is recruiting. You can begin a search at decentrialz.com to see what is currently available.