# Successful treatment of type I cryoglobulinemia with a combination of carfilzomib, cyclophosphamide, and dexamethasone: a case report and literature review

## TL;DR

A patient with a rare blood disorder successfully responded to a new drug combination after failing previous treatments.

## Contribution

Demonstrates successful treatment of bortezomib-resistant type I cryoglobulinemia using carfilzomib-based therapy.

## Key findings

- KCd therapy (carfilzomib, cyclophosphamide, dexamethasone) effectively treated a bortezomib-resistant case of type I cryoglobulinemia.
- The patient remained in remission for over 3 years with continued carfilzomib maintenance therapy.
- This case suggests carfilzomib-based regimens may be a promising option for refractory type I cryoglobulinemia.

## Abstract

Type I cryoglobulinemia is typically associated with hematological malignancies such as B-cell lymphomas and plasma cell neoplasms. Its treatment basically targets underlying hematological malignancies, and the prognosis remains unsatisfactory. Despite several reports of type I cryoglobulinemia treated with bortezomib-based regimens, little is available on the treatment of bortezomib-resistant cases. We report a case of severe type I cryoglobulinemia associated with plasma cell neoplasm, refractory to bortezomib and daratumumab, which was successfully managed with a combination of carfilzomib, cyclophosphamide, and dexamethasone (KCd therapy). No sign of relapse has been seen for more than 3 years with maintenance therapy with ongoing carfilzomib. This case highlights the potential efficacy of carfilzomib-based regimens in bortezomib-resistant type I cryoglobulinemia, offering a promising option for cases refractory to conventional treatments.