The association between immune checkpoint or BRAF/MEK inhibitor therapy and uveitis in patients with advanced cutaneous melanoma.

BACKGROUND: Treatment with immune checkpoint and BRAF/MEK inhibitors has significantly improved the survival of patients with advanced cutaneous melanoma and other metastatic malignancies. Therapy-related uveitis is a rare ocular adverse event, which may potentially lead to legal blindness. The epidemiology of treatment-related uveitis is currently insufficiently known. PATIENTS AND METHODS: In this cohort study, we asked whether exposure to either immune checkpoint or BRAF/MEK inhibitors was associated with a higher risk of developing uveitis compared with the general population. Based on a Bayesian framework, we estimated the probability of developing uveitis with a right-censored, exponential survival model using data from the Zurich Melanoma Registry. The registry included all adult patients treated for advanced cutaneous melanoma between January 2008 and December 2018 at the University Hospital of Zurich, Switzerland. RESULTS: In total, 304 patients (64%) were treated with immune checkpoint and 186 patients (38%) with BRAF/MEK inhibitors. Median follow-up time was 74 days (interquartile range: 57-233 days). Eleven patients developed uveitis and 30 patients died. We estimated the probability of developing uveitis per year in the general population as 0.05% (95% credibility interval [CrI]: 0.02%-0.1%). Corresponding posterior probabilities of treatment-related uveitis were 3.48% (95% CrI: 0.93%-7.49%) and 5.04% (95% CrI: 2.07%-9.19%) for immune checkpoint or BRAF/MEK inhibitors (posterior probability for difference: 76%). CONCLUSIONS: Immune checkpoint and particularly BRAF/MEK inhibitor therapies are associated with an increase in the risk of developing uveitis. Treatment-related uveitis is not associated with systemic adverse events of immune checkpoint or BRAF/MEK inhibitors.

Long-Term Response to Intermittent Binimetinib in Patients with NRAS-Mutant Melanoma.

Melanoma can be classified based on the detection of relevant oncogenic driver mutations. These mutations partially determine a patient's treatment options. MEK inhibitors have demonstrated little efficacy in patients with NRAS-mutated melanoma owing to primary and secondary resistance. We report two patients with NRAS-mutant metastatic melanoma with long-term response to intermittent MEK-inhibitor binimetinib therapy. Intermittent dosing schedules could play a key role in preventing resistance to targeted therapy. This article highlights the efficacy of an intermittent dosing schedule, toxicities associated with binimetinib, and possible mechanisms preventing resistance in targeted therapy. Intermittent MEK-inhibitor therapy may be considered in patients with NRAS-mutated melanoma that have failed all standard therapies. KEY POINTS: Melanomas harbor NRAS mutations in 10%-30% of the cases. These mutations promote hyperactivation of the MAPK pathway, leading to proliferation and prolonged survival of tumor cells. Currently, drugs directly targeting NRAS are not available. Downstream inhibition of the MAPK pathway can be considered as a therapeutic option after immunotherapeutic failure. Intermittent administration of kinase inhibitors might be the way to partially overcome the development of drug resistance by (a) inducing a fitness deficit for drug-resistant cells on treatment break, (b) increasing the immunogenicity, and (c) inducing apoptosis and cell cycle arrest. It also enhances expression of numerous immunomodulating molecules, and reduction of immunosuppressive factors, which suggests better access of the immune system to the tumor.

Pembrolizumab-triggered Uveitis: An Additional Surrogate Marker for Responders in Melanoma Immunotherapy?

Immunotherapy leads to significantly prolonged survival of patients with metastatic melanoma. Autoimmune side effects including colitis, dermatitis, and endocrine abnormalities are common in patients treated with ipilimumab [anti-CTLA4 (cytotoxic T-lymphocyte-associated protein 4)]. Antibodies such as pembrolizumab that interfere with the PD-1 (programmed cell death 1)/PD-L1 pathway show greater efficacy and less toxicity than ipilimumab. Here we report 2 cases of pembrolizumab-induced uveitis associated with complete or partial tumor response. We suggest that uveitis may serve as a surrogate marker for a tumor response to therapy with pembrolizumab.