Anti-programmed cell death-1 therapy and insulin-dependent diabetes: a case report

Area of Science:

• Oncology
• Immunology
• Endocrinology

Background:

• Anti-programmed cell death-1 (PD-1) antibodies (pembrolizumab, nivolumab) are FDA-approved for advanced melanoma.
• Immune checkpoint inhibitors can cause endocrine adverse events.
• Autoimmune diabetes has not been previously described with PD-1 inhibition.

Observation:

• A case of autoimmune diabetes developed in an adult patient treated with pembrolizumab.
• The patient presented with high serum titres of anti-glutamic acid decarboxylase antibodies.
• The patient possessed a high-risk human leucocyte antigen type for type 1 diabetes.

Findings:

• The clinical presentation, autoantibodies, and human leucocyte antigen type strongly suggest an autoimmune etiology for the diabetes.
• PD-1 inhibition is implicated as the likely trigger for the autoimmune phenomenon.
• This represents the first described case of autoimmune diabetes secondary to PD-1 inhibition.

Implications:

• Insulin-dependent diabetes may be a rare but significant immune-related adverse event of anti-PD-1 therapy.
• Clinicians should consider monitoring for diabetes in patients receiving PD-1 inhibitors.
• Further research is warranted to understand the mechanisms and incidence of this adverse event.