Roswell Park Cancer Institute offers IL-2 therapy for the treatment of advanced metastatic melanoma and for advanced metastatic kidney cancer. IL-2 therapy is a biological therapy and the only Food and Drug Adminstration (FDA) approved immunotherapy option for melanoma and kidney cancer. It works to boost the body’s immune system, helping the body fight the cancer.

For select patients, IL-2 can be “nothing short of extraordinary”

“There are people who had extensive metastatic disease who are alive decades after IL-2 therapy,” says Michael Wong, MD, PhD, FRCPC, Medical Director of Clinical Drug Development and Director of the IL-2 program at Roswell Park Cancer Institute. “It can treat patients even with high tumor burden, completely eliminating the tumors from the patient’s body.”

He recalls one especially memorable case in which a patient with approximately 100 tumors in his lungs emerged from IL-2 therapy with only one tumor remaining: “After watching the remaining tumor for a while, we decided to take it out, and it was necrotic; there were no live tumors,” says Wong. “Now, four years later, the man is still free of tumors.”

Identifying the best candidates Wong cautions that the likelihood of realizing either a complete or partial response to IL-2 hinges on two principal challenges:

• first, identifying patients who are most likely to achieve a response, and
• second, ensuring that the potent immunotherapy is delivered safely.

With one of the busiest IL-2 clinics in the United States—serving patients from several countries, including Canada—the RPCI team has developed a high level of expertise in selecting the best candidates and helping them manage IL-2’s significant side effects.

Studies show that IL-2 achieves a complete response in about 10% of patients who receive the treatment.

“The tumor disappears completely and is invisible on physical examination, x-ray scan and CAT scan,” explains Wong. Another 10% achieve partial response, in which “evidence of cancer can still be found on physical exam or x-ray, but it’s smaller than it was before, and stable. A partial response is also very useful, because it can last for years. “Because, at best, only one in five people will benefit from high-dose IL-2, it’s important to select them carefully.”

Dramatic immune response

Wong doesn’t downplay the severity of IL-2’s side effects. “It’s hard on patients,” he emphasizes. “We’re inducing the immune system to think that the patient has a severe, life-threatening infection. That’s not the case, but the consequence of tricking the body down this path is that it fires off the immune system in powerful ways. “Consequently, patients experience significant problems with blood pressure, breathing, and [cardiac function]. So we screen our patients very carefully before they come into the program, and they’re treated in only one specific place in this hospital. “Candidates undergo a cardiac stress test, a pulmonary function test, and a scan to confirm that there’s no cancer in the brain. We also look for good kidney and liver function, as well as characteristics related to response that we’ve learned about through our collective experience. The patient must be healthy enough so the immune system is strong enough to fight the cancer.”

The treatment process

High-dose IL-2 immunotherapy is delivered only as an inpatient procedure. Patients are admitted on Monday, and most are discharged Saturday morning. They skip the following week, then return for a second week of treatment. Eight weeks after the second treatment, they return for scans to evaluate the response.

Wong says it’s important to keep in mind that, because IL-2 is an immunotherapy rather than chemotherapy, response is not immediate; it takes time for the immune system to “kick in—on average, a couple of months. That’s why we re-image them and re-study them for response about eight weeks after IL-2.

“With some individuals, we’re unable to treat them, because the cancer is moving too quickly for IL-2 to help them. But IL-2 is not the only thing we can do for them; it’s always part of a larger plan.”

Taking IL-2 to the next level

Because RPCI’s mission encompasses both patient care and research, Wong and his colleagues are investigating why some patients don’t respond to IL-2 immunotherapy. “We know we can achieve cures; why can’t we achieve more cures?” he asks. He’s part of a group of researchers who are analyzing personal traits, blood and tumor samples of patients who do respond to high-dose IL-2 therapy for kidney cancer, to determine whether the new biomarker CA-IX is a predictor of positive outcome. A clinical research study is currently underway to answer that question, and a second IL-2 study, involving metastatic melanoma, is under review by RPCI’s Institutional Review Board. To keep apprised of open clinical trials at RPCI, visit www.roswellpark.org/Patient_Care and choose Clinical Trials – Clinical Trials Search.