ipilimumab

Ipilimumab is a human monoclonal antibody that targets CTLA-4, a negative regulator of T cell activation. It is used as an immunotherapy for cancer, particularly metastatic melanoma. Developed by Medarex and licensed to Bristol-Myers Squibb, it is marketed under the brand name Yervoy.

By blocking CTLA-4, ipilimumab enhances T cell activation and proliferation, promoting anti-tumor immune responses. It received FDA approval in 2011 for unresectable or metastatic melanoma. It may be used as monotherapy or in combination with nivolumab, an anti-PD-1 antibody, for some advanced cancers and specific treatment regimens.

Administration is by intravenous infusion. For melanoma, a common regimen is 3 mg/kg every three weeks for four doses. In combination therapy with nivolumab, different dosing schedules are used, and higher doses have been explored in clinical trials.

Adverse effects are largely immune-related, reflecting increased immune activity. These include colitis or diarrhea, dermatitis, hepatitis, and endocrinopathies such as hypophysitis or thyroiditis. Management often requires corticosteroids or other immunosuppressants and careful monitoring for signs of organ inflammation.

Ipilimumab was the first immune checkpoint inhibitor approved for cancer treatment, marking a milestone in cancer immunotherapy. Ongoing research continues to define its role in various malignancies and in combination regimens, as well as strategies to manage immune-related toxicities.