Dr. Gibney on Determining Optimal Treatment Duration With Anti–PD-1 Agents in Melanoma

Geoffrey T. Gibney, MD, co-leader of the Melanoma Disease Group, and a member of the Developmental Therapeutics (Phase I) program at the Lombardi Comprehensive Cancer Center and MedStar Cancer Network, MedStar Georgetown University Hospital, discusses efforts made to determine the optimal duration of treatment with anti–PD-1 agents in patients with melanoma.

When examining anti–PD-1 therapy in patients with melanoma it is not only important to establish the efficacy of agent, but also to determine how to safely administer it, Gibney says. The optimal duration of therapy has never been well defined, adds Gibney. Many studies that have led to the FDA approvals of agents such as pembrolizumab (Keytruda)and nivolumab (Opdivo) did not have a definitive time established to discontinue treatment in patients who were tolerating the agent well and responding, Gibney explains. Due to this, treatment duration has been a topic of discussion in the community.

In the phase 3 KEYNOTE-006 and phase 1 KEYNOTE-001 trials, treatment with pembrolizumab was discontinued after 2 years of treatment and after 2 subsequent scans showing a complete response, respectively, Gibney notes. However, these studies did not conclusively determine the optimal duration of treatment.

Currently, it is thought that 2 years may be the appropriate treatment duration for anti–PD-1 agents; however, some might consider continuing treatment further, Gibney concludes.