The pharmacological management of hairy cell leukemia

ABSTRACT

Introduction

Hairy cell leukemia (HCL) is a B-cell lymphoid malignancy that accounts for approximately 2% of all leukemias. Treatment with purine nucleoside analogs (PNA) results in a high response rate and remains the standard of care. Long term follow-up shows that most patients relapse and require retreatment. Newer combination strategies and agents have emerged to try to reduce the relapse rate and to address cases of PNA refractoriness.

Areas covered

The authors reviewed the literature on the pharmacological management of HCL, including recent studies that led to new agents being incorporated into practice.

Expert opinion

Combination of cladribine plus rituximab produces a high rate of measurable residual disease-negative complete remission. In our center, newly diagnosed patients are offered cladribine followed by 8 weekly doses of rituximab in an ongoing phase II trial. Patients in first relapse are also offered this combination if they were initially treated with a single-agent PNA, or if the remission duration was ≥5 years after first-line cladribine plus rituximab. Patients who relapse within 5 years are offered therapy with a novel agent that may include the BRAF inhibitor vemurafenib, alone or in combination with rituximab, dabrafenib in combination with trametinib, the BTK inhibitor ibrutinib, or moxetumomab pasudotox.

KEYWORDS:

• Hairy Cell Leukemia
• pharmacological management
• cladribine
• rituximab

Article highlights

• Hairy cell leukemia is a rare indolent B-cell malignancy that responds very well to initial treatment with purine nucleoside analogs.

• Unfortunately, most of the patients will eventually relapse.

• The introduction of the purine nucleoside analogs to the treatment of HCL marked a turning point in this disease.

• The combination of cladribine plus the anti-CD20 monoclonal antibody rituximab induces a deeper level of durable response.

• More recently, newer, non-chemotherapeutic agents have been investigated in relapsed/refractory HCL with encouraging results.

This box summarizes the key points contained in the article.

Declaration of interest

F Ravandi-Kashani has received consultancy fees from AstraZeneca and Novartis. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This manuscript has not been funded.