Utility of Low-Dose Duvelisib for Advanced Mycosis Fungoides: A Single-Institution Study

Oncologist. 2024 Mar 4;29(3):272-274. doi: 10.1093/oncolo/oyad345.


Duvelisib, a small-molecule phosphatidylinositol 3-kinase-δ,γ inhibitor, has shown efficacy for mycosis fungoides (MF) at dosage ranges of 25-100 mg twice daily (BID), but with significant toxicity. We conducted a retrospective cohort study of patients with advanced MF treated with low-dose duvelisib (15 mg every other day to BID), in an effort to minimize toxicity. A total of 7 patients were included. The overall response rate on duvelisib was 71%, with the remaining patients maintaining stable disease. Mean modified Severity Weighted Assessment Tool score improved by 57.4% and mean percent body surface area involved improved by 52%. Median progression-free survival was 10.3 months. Adverse events occurred in 4 of 7 patients, the most common being fatigue (2/7; grades 1-2), nausea (2/7; grades 1-2), and transaminitis (2/7; grade 3). Overall, low-dose duvelisib showed efficacy for advanced MF with less toxicity, providing a rationale for its use as monotherapy and potentially combinatorial therapy.

Keywords: PI3K-δ,γ inhibitor; cutaneous T-cell lymphoma; duvelisib; mycosis fungoides.

MeSH terms

  • Humans
  • Isoquinolines / adverse effects
  • Mycosis Fungoides* / chemically induced
  • Mycosis Fungoides* / drug therapy
  • Purines*
  • Retrospective Studies
  • Skin Neoplasms* / drug therapy


  • duvelisib
  • Isoquinolines
  • Purines