Immune-checkpoint inhibitors in melanoma and kidney cancer: from sequencing to rational selection

Immune-checkpoint inhibitors (ICPIs), including antibodies against cytotoxic T-lymphocyte associated antigen 4 and programmed cell death protein 1, have been shown to induce durable complete responses in a proportion of patients in the first-line and refractory setting in advanced melanoma and renal cell carcinoma. In fact, there are several lines of both targeted agents and ICPI that are now feasible treatment options. However, survival in the metastatic setting continues to be poor and there remains a need for improved therapeutic approaches. In order to enhance patient selection for the most appropriate next line of therapy, better predictive biomarkers of responsiveness will need to be developed in tandem with technologies to identify mechanisms of ICPI resistance. Adaptive, biomarker-driven trials will drive this evolution. The combination of ICPI with specific chemotherapies, targeted therapies and other immuno-oncology (IO) drugs in order to circumvent ICPI resistance and enhance efficacy is discussed. Recent data support the role for both targeted therapies and ICPI in the adjuvant setting of melanoma and targeted therapies in the adjuvant setting for renal cell carcinoma, which may influence the consideration of treatment on subsequent relapse. Approaches to select the optimal treatment sequences for these patients will need to be refined.

Cancer immunotherapy: new applications in urologic oncology

PURPOSE OF REVIEW

Over the last 10 years, harnessing of the immune system to attack tumors has been one of the major breakthroughs in cancer, primarily through the use of immune checkpoint inhibitors (ICIs). This review will summarize current immune treatments in urologic malignancies and ongoing trials with novel combinations and in different disease settings.

RECENT FINDINGS

Patients with urologic malignancies such as kidney and bladder cancer have benefited significantly from these advances with the approval of ICIs in both of these diseases. In addition, older immune therapies have also been used in these malignancies. For example, kidney cancers, which are traditionally unresponsive to chemotherapy, can respond to immune activation by cytokines. Prostate cancers, too, have immune therapies, such as sipuleucel-T, a dendritic cell vaccine. Combining ICIs with these older treatments as well as with molecularly targeted therapies and chemotherapies are currently underway.

SUMMARY

The ICIs have changed the way urologic malignancies are treated and newer combinations are likely to alter the therapeutic landscape in these diseases dramatically in the coming years.

Immune checkpoint inhibitors in renal cell carcinoma

The immune system has long been known to play a critical role in the body's defence against cancer, and there have been multiple attempts to harness it for therapeutic gain. Renal cancer was, historically, one of a small number of tumour types where immune manipulation had been shown to be effective. The current generation of immune checkpoint inhibitors are rapidly entering into routine clinical practice in the management of a number of tumour types, including renal cancer, where one drug, nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody (mAb), is licensed for patients who have progressed on prior systemic treatment. Ongoing trials aim to maximize the benefits that can be gained from this new class of drug by exploring optimal timing in the natural course of the disease as well as combinations with other checkpoint inhibitors and drugs from different classes.