Ipilimumab (Yervoy) for Stage IV Cancer
Also known as: Yervoy, MDX-010
The first checkpoint inhibitor approved for cancer, targeting CTLA-4 to enhance T cell priming — complementary to PD-1 blockade.
Mechanism of Action
Ipilimumab blocks CTLA-4, a co-inhibitory receptor that competes with CD28 for B7 ligand binding on antigen-presenting cells. By preventing CTLA-4-mediated inhibition, it enhances T cell priming, proliferation, and effector function in lymph nodes. This mechanism is complementary to PD-1 blockade (which acts in the tumor microenvironment).
General mechanism: Anti-CTLA-4 monoclonal antibody. Enhances T cell priming and activation by removing co-inhibitory signals.
Current Evidence
Landmark survival benefit in advanced melanoma (MDX010-20 trial). Combination with nivolumab is now standard in melanoma, renal cancer, and mesothelioma. Long-term follow-up shows durable 10+ year responses in a subset of melanoma patients.
Clinical Status: FDA-approved for melanoma, renal cell carcinoma, MSI-high colorectal cancer, hepatocellular carcinoma, NSCLC, and mesothelioma (in combination).
Safety Profile
Higher toxicity than PD-1 inhibitors. Colitis, hepatitis, dermatitis, and endocrinopathies occur in 30-40% of patients. Dose-dependent toxicity.
Key Research Questions
- Can lower-dose ipilimumab combinations maintain efficacy with reduced toxicity?
- What patient selection criteria optimize the risk-benefit of dual checkpoint blockade?
- Does ipilimumab have a role in adjuvant settings beyond melanoma?