Restoring Immune Mediated Disease Control by Ipilimumab Re-exposition in a Heavily pretreated Patient With MSI-H mCRC

Background: Immune-Checkpoint-inhibitors (ICIs) are approved in first line therapy of microsatellite-instable, deficient miss-match-repair (MSI-H-dMMR) metastatic colorectal cancer (mCRC), and in second line after standard chemotherapy. Evidence supporting immunotherapy after immunotherapy is scarce.Case report: This case report highlights the course of a heavily pretreated patient with MSI-H mCRC with progression after multiple local therapies, standard chemotherapies and pembrolizumab. After 4 cycles of ipilimumab and nivolumab followed by nivolumab-maintenance he achieved a long-lasting disease control of 22 months. After further subsequent progression he regained immune mediated disease control by a second boost of ipilimumab. Conclusion: Re-exposition with ipilimumab is a potential option to restore immune-mediated-disease-control in patients with preceding long-lasting response to ipilimumab/nivolumab and with dMMR-tumors. The clinical situation of progress after long-lasting disease control on ICIs becomes more common and is an opportunity to investigate potential strategies for restoring immune mediated disease control. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

This case report highlights the potential option of re-exposure to Ipilimumab as a strategy to restore immune-mediated disease control in patients with MSI-H mCRC who have had a long-lasting response to Ipilimumab/Nivolumab.