Use of chlormethine 0.04% gel for mycosis fungoides after treatment with topical chlormethine 0.02% gel: A phase 2 extension study

Case report: Canadian consensus on chlormethine gel use in mycosis fungoides-CTCL: literature review and real-world experience

Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma (CTCL), representing the majority of all lymphomas arising in the skin. The disease treatment focuses on managing symptoms and preventing disease evolution. To date, there is no gold standard for MF-CTCL treatment. Chlormethine, a DNA alkylating agent, is a long-known treatment for CTCL. The new chlormethine 0.02% gel (CL-gel) formulation provides proven efficacy and ease of application, improving patient compliance and outcome. The current consensus paper and real-world experience with CL-gel in the treatment of early-stage MF-CTCL may help meet the unmet need for treatments in Canada. A modified Delphi process comprised a virtual meeting and an online follow-up. A panel of 9 board-certified dermatologists with expertise in cutaneous lymphoma and 1 radiation oncologist discussed the systematic literature review results, drew from clinical experience and the opinion of the panel to adopt and agree on five consensus statements. The panel shared real-world patient cases to illustrate the use of chlormethine gel in a variety of patients across Canada. Five real-world patient cases were provided to illustrate the panels' use of chlormethine gel.

Advances in the pharmacological management of cutaneous T-cell lymphoma

INTRODUCTION

Current treatment guidelines for cutaneous T cell lymphoma (CTCL) advocate a stage-driven approach, considering clinical presentation, symptom burden, and patient comorbidities. Therapy selection hinges on factors like disease subtype, severity, and treatment availability. The primary goal is to enhance the quality of life by mitigating symptoms, as achieving lasting complete remission is infrequent.

AREAS COVERED

Over the past decade (2013-2023), the therapeutic landscape of CTCL has experienced substantial transformation with the introduction of innovative therapies. This review explores the main pivotal developments in traditional treatment schedules and recently introduced drugs, aiming to offer clinicians and researchers a thorough perspective on the decade's progress in the field.

EXPERT OPINION

Despite the progress made in CTCL therapeutics, ranging from topical chemotherapeutics to immunomodulatory agents, several unmet needs persist. Firstly, there is a pressing need for the incorporation of readily available predictors for treatment response, encompassing clinical, pathological, and molecular features. Secondly, a more profound comprehension of the tumor microenvironment is imperative to optimize the landscape of targetable molecules. Lastly, the undertaking of studies on combination regimens should be encouraged as it enhances therapy efficacies by synergistically combining agents with diverse modes of action.

Advances in the treatment of mycoses fungoides and Sézary syndrome: a narrative update in skin-directed therapies and immune-based treatments

Mycoses fungoides (MF) and Sézary syndrome (SS) are cutaneous T-cell lymphomas that are often challenging to manage given the absence of reliably curative therapies, at times high symptom burden with significant detriment to quality of life, and need for ongoing treatment for disease and symptom control. Recent developments in skin-directed treatments include optimizing the use of existing topical therapies, the introduction of known dermatological agents and treatment modalities for the specific treatment of MF/SS (such as mechlorethamine gel, calcineurin inhibitor creams, and photodynamic therapy), and novel local and topical agents. For advanced disease, dedicated clinical trials have translated to exciting progress, leading to the approval of brentuximab vedotin (2017) and mogamulizumab (2018) for relapsed MF/SS. Additional studies of other active systemic agents, including various cellular therapies, represent further attempts to add to the therapeutic armamentarium in treating MF/SS. In this review, we highlight these recent advancements, ranging from optimization of skin-directed therapies to the introduction of novel systemic agents. We focus on therapies approved in the preceding five years or under investigation in advanced-phase clinical trials.

Chlormethine Gel for Patients with Mycosis Fungoides Cutaneous T Cell Lymphoma: A Review of Efficacy and Safety in Clinical Trial and Real-World Settings

Mycosis fungoides (MF) is a rare disease and is the most common form of cutaneous T cell lymphoma. Topical chlormethine (CL) gel is the first cytotoxic chemotherapy gel that was specifically developed for treatment of MF. In this review, we provide an overview of all available data on the use of CL gel for treatment of patients with MF. On the basis of the current data collected, CL gel is highly effective, with good response rates observed both in clinical trial and real-world settings. While the gel is approved for monotherapy, it is also used in combination with concomitant skin-directed or systemic therapies in clinical practice. Responses to CL gel treatment can be rapid, but they also frequently occur with a delayed onset of up to 6 months. This indicates that continued treatment with CL gel is important. CL gel has a manageable safety profile, with most adverse events being mild and skin related. Contact dermatitis is one of the more common skin-related adverse events to occur with CL gel treatment that can potentially lead to treatment discontinuation. The data from the literature indicate that patients being treated with CL gel should be monitored carefully, and that dermatitis must be managed effectively to allow patients to continue treatment and achieve the best possible response to treatment.

Chlormethine Gel Versus Chlormethine Ointment for Treatment of Patients with Mycosis Fungoides: A Post-Hoc Analysis of Clinical Trial Data

BACKGROUND

Chlormethine gel was approved for treatment of mycosis fungoides, the most common cutaneous T-cell lymphoma, on the basis of results from study 201 and study 202. A post-hoc analysis of study 201 found interesting trends regarding improved efficacy of chlormethine gel vs ointment and noted a potential association between dermatitis and clinical response.

OBJECTIVE

To expand these results by performing a post-hoc analysis of study 202.

PATIENTS AND METHODS

Patients received chlormethine gel or ointment during study 201 (12 months) and higher-concentration chlormethine gel during study 202 (7-month extension). Response was assessed using Composite Assessment of Index Lesion Severity (CAILS). Associations between treatment frequency, response, and skin-related adverse events (AEs) were assessed using multivariate time-to-event analyses. Time-to-response and repeated measures analyses were compared between patients who only used chlormethine gel and those who switched from ointment to gel.

RESULTS

No associations were seen between treatment frequency and improved skin response (CAILS) or AE occurrence within the 201/202 study populations. However, an association was observed specifically between contact dermatitis and improved CAILS response at the next visit (p < 0.0001). Patients who used chlormethine gel during both studies had a significantly (p < 0.05) shorter time to response and higher overall response rates than patients who initiated treatment with ointment.

CONCLUSIONS

This post-hoc analysis shows that patients who initiated treatment using chlormethine gel had faster and higher responses compared with patients who initially used chlormethine ointment for 12 months. The development of contact dermatitis may be a potential prognostic factor for response.

TRIAL REGISTRATION NUMBERS AND DATES OF REGISTRATION

Study 201: NCT00168064, September 14, 2002; Study 202: NCT00535470, September 26, 2007.