Romidepsin Evidence Guide
Romidepsin (Istodax) is FDA-approved for cutaneous T-cell lymphoma and peripheral T-cell lymphoma with Phase 2/3 data supporting meaningful response rates in these difficult-to-treat malignancies. As a bicyclic depsipeptide HDAC inhibitor, it has a unique cyclopeptide structure within its drug class. A well-validated niche oncology drug with a defined patient population.
Our Take
Romidepsin (Istodax) is FDA-approved for cutaneous T-cell lymphoma and peripheral T-cell lymphoma with Phase 2/3 data supporting meaningful response rates in these difficult-to-treat malignancies. As a bicyclic depsipeptide HDAC inhibitor, it has a unique cyclopeptide structure within its drug class. A well-validated niche oncology drug with a defined patient population.
- Best for
- Cutaneous T-cell lymphoma, peripheral T-cell lymphoma, HDAC inhibitor pharmacology research
- Evidence grade
- Level A
- Confidence
- High
- Starting point
- 14mg/m² IV over 4 hours on days 1, 8, and 15 of a 28-day cycle
Benefits and Evidence
- Cutaneous T-Cell Lymphoma: Level A, includes human evidence - Phase 2 trials showed overall response rate of 34% in relapsed/refractory CTCL, with durable responses. Approved based on two pivotal trials.
- Peripheral T-Cell Lymphoma: Level A, includes human evidence - Overall response rate of 25-38% in relapsed/refractory PTCL. Some patients achieved complete responses lasting over 12 months.
- Cardiac Effects: Level B, includes human evidence - ECG changes including ST-T wave changes and QT prolongation reported. Requires electrolyte monitoring and ECG surveillance.
Side Effects and Warnings
- Nausea and vomiting
- Fatigue
- Thrombocytopenia
- ECG changes (T-wave, ST-segment)
- Dysgeusia (altered taste)
- Infections
- ECG monitoring required - QT prolongation risk
- Electrolyte abnormalities must be corrected before dosing
Research Dosage References
- <strong>Intravenous infusion</strong> - 14 mg/m2 - Days 1, 8, 15 of 28-day cycle - Infuse over 4 hours. Ensure potassium >4.0 mEq/L and magnesium >2.0 mg/dL before dosing.
Mechanism of Action
Romidepsin acts as a prodrug HDAC inhibitor through epigenetic modulation: 1. Prodrug activation: Intracellular reduction of the disulfide bond releases the active thiol form that chelates zinc in the HDAC active site. 2. Class I HDAC inhibition: Potently inhibits HDAC1, HDAC2, HDAC3, and HDAC8, leading to hyperacetylation of histones. 3. Gene re-expression: Restores expression of epigenetically silenced tumor suppressor genes (p21, p53 pathway genes) in lymphoma cells. 4. Cell cycle arrest and apoptosis: Hyperacetylation leads to G1/G2 cell cycle arrest and activation of both intrinsic and extrinsic apoptotic pathways.
Legal Status
FDA-approved for cutaneous T-cell lymphoma (2009) and peripheral T-cell lymphoma (2011). Available by prescription only. Marketed as Istodax by Celgene/Bristol-Myers Squibb.
Primary Sources
- Pivotal phase 2 trial of romidepsin in cutaneous T-cell lymphoma. J Clin Oncol, 2010.
- Romidepsin for the treatment of relapsed/refractory peripheral T-cell lymphoma. Blood, 2012.
- Romidepsin: a histone deacetylase inhibitor for the treatment of T-cell lymphomas. Expert Opin Drug Metab Toxicol, 2011.