Case series of cutaneous T-cell lymphomas treated with bexarotene-based therapy

Experience With Bexarotene to Treat Cutaneous T-Cell Lymphomas: A Study of the Spanish Working Group of Cutaneous Lymphomas

BACKGROUND AND OBJECTIVES

Bexarotene has been approved to treat advanced stage cutaneous T-cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL.

MATERIAL AND METHOD

This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or Sézary syndrome (42) on a 10-year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals.

RESULTS

A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27-95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1-114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment-related grade 5 adverse events were reported.

CONCLUSIONS

Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL.

Effects of Body Mass Index on Hypertriglyceridemia Associated with Oral Bexarotene Therapy: A Post Hoc Analysis of an Open-Label Comparative Clinical Study of Combined Bexarotene and Phototherapy Versus Bexarotene Monotherapy for Japanese Patients with Cutaneous T-Cell Lymphoma

BACKGROUND

Bexarotene, which has been approved for use in Japan since 2016, is an effective drug for cutaneous T-cell lymphoma; however, careful management is imperative because of its adverse events. We previously demonstrated the severity of bexarotene-associated hypertriglyceridemia and the need for bexarotene dose reduction for patients with cutaneous T-cell lymphoma and high body mass index (BMI); however, high BMI does not affect the efficacy of combined bexarotene and phototherapy treatment.

OBJECTIVE

This study aimed to verify the effects of BMI on hypertriglyceridemia associated with oral bexarotene therapy.

METHODS

We conducted a post hoc analysis of data from a previous randomized, open-label clinical study that compared combined bexarotene-phototherapy treatment with bexarotene monotherapy for cutaneous T-cell lymphoma by dividing patients into two groups based on BMI (<23 kg/m2 and ≥23 kg/m2).

RESULTS

No statistically significant association was observed between patients with BMI ≥23 kg/m2 and severe hypertriglyceridemia; however, there was a significant association between BMI ≥23 kg/m2 and severe hypertriglyceridemia for patients who received bexarotene monotherapy, but not for those who received combined bexarotene-phototherapy treatment. The exact reasons for the discrepancies between the results of this thorough analysis and those of our past research are unclear. However, high BMI may be a risk factor for hypertriglyceridemia. Additional unidentified risk factors could also affect treatment outcomes.

CONCLUSION

High BMI is the primary reason for hypertriglyceridemia-associated bexarotene dose reduction; however, unexplored risk factors other than high BMI could exist.

Experience With Bexarotene to Treat Cutaneous T-Cell Lymphomas: A Study of the Spanish Working Group of Cutaneous Lymphomas

BACKGROUND AND OBJECTIVES

Bexarotene has been approved to treat advanced stage cutaneous T-cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL.

MATERIAL AND METHOD

This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or Sézary syndrome (42) on a 10-year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals.

RESULTS

A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27-95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1-114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment-related grade 5 adverse events were reported.

CONCLUSIONS

Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL.

Comparison of the Efficacy and Safety of Bexarotene and Photo(Chemo)Therapy Combination Therapy and Bexarotene Monotherapy for Cutaneous T-Cell Lymphoma

Introduction

Cutaneous T-cell lymphoma (CTCL) is a chronic condition with low malignancy. The combined use of therapeutic agents and photo(chemo)therapy is widely applied for the treatment of CTCL. The efficacy and safety of bexarotene and photo(chemo)therapy combination therapy were previously confirmed in Japanese patients with CTCL. The efficacy and safety of the bexarotene and photo(chemo)therapy combination therapy was compared with bexarotene monotherapy in Japanese patients with CTCL.

Methods

This was a randomized, open-label, two-parallel-group, active-control specified clinical study in Japanese patients diagnosed with CTCL carried out over 8 weeks with a study extension conducted at two institutions. This study was registered in Japan Registry of Clinical Trials (jRCTs041180094).

Results

In the combination therapy group, 22 subjects received oral bexarotene (300 mg/m² body surface area) once daily, followed by bath-psoralen and ultraviolet (UV) A or narrowband UVB. In the monotherapy group, 24 subjects received oral bexarotene (300 mg/m²) once daily. The efficacy analysis using the modified Severity-Weighted Assessment Tool, which included 39 patients, showed a response rate of 81.0% (17/21) in the combination therapy group and 83.3% (15/18) in the monotherapy group. No statistically significant difference was detected between groups. In the combination therapy group, four subjects showed a complete clinical response or complete response, and subjects with a partial response exhibited a high rate of skin lesion resolution, significantly better than in the monotherapy group. In the safety analysis, which included 46 treated subjects (22 in the combination therapy group and 24 in the monotherapy group), no adverse events or adverse drug reactions were reported in either group.

Conclusion

Both bexarotene and photo(chemo)therapy combination therapy and bexarotene monotherapy were therapeutically effective in Japanese patients with CTCL and well tolerated. Combination therapy led to a higher skin lesion resolution rate and greater therapeutic effects compared with monotherapy.

Trial Registration

jRCTs041180094.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-021-00655-0.

This study evaluated the efficacy and safety of bexarotene monotherapy compared with bexarotene and photo(chemo)therapy combination therapy in Japanese patients with cutaneous T-cell lymphoma (CTCL). The study was a randomized, open-label, two-parallel-group, active-control specified clinical study in patients diagnosed with CTCL performed over an 8-week period with a study extension conducted in two institutions. In the combination therapy group, bexarotene (300 mg/m² body surface area) was administered orally once daily to 22 subjects, followed by treatment with bath-psoralen and ultraviolet A (bath-PUVA) or narrowband UVB. In the bexarotene monotherapy group, bexarotene (300 mg/m²) was administered orally once daily to 24 subjects. Efficacy was assessed using the modified Severity-Weighted Assessment Tool. Among the 39 subjects analyzed for treatment efficacy, the response rate of the combination therapy group was 81.0% (17/21) and that of the monotherapy group was 83.3% (15/18). Differences between the two treatment groups were not statistically significant. Of the 21 subjects in the combination therapy group, 4 had a complete clinical response or complete response, and those with a partial response showed a higher skin lesion resolution rate than in the monotherapy group. The safety analysis revealed no reports of adverse events or adverse drug reactions among the 46 treated subjects (combination therapy group = 22; monotherapy group = 24). Thus, both bexarotene and photo(chemo)therapy combination therapy and bexarotene monotherapy were therapeutically effective and well tolerated in Japanese patients with CTCL. Patients receiving the combined therapy, however, showed a higher rate of skin lesion resolution.

Safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma: Real-world experience from post-marketing surveillance

To establish real-world evidence about the safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma, we conducted a nationwide cohort study using data from post-marketing surveillance for bexarotene treatment. In total, 294 patients with cutaneous T-cell lymphoma were identified between June 2016 and June 2018. Of these, 267 patients were included as the safety analysis set. Of the 267 patients, 175 were included in the efficacy analysis set. Of these, 139 patients had mycosis fungoides, including 46 with early stage disease and 93 with advanced stage disease. Among the 139 patients with mycosis fungoides, the objective response rate was 46.8%. A significant difference in objective response rate was detected between patients who started with bexarotene at 300 mg/m² (61.6%) and patients who started with bexarotene at less than 300 mg/m² (22.6%, p < 0.001). Of the 139 patients with mycosis fungoides, 92 were treated with a combination of bexarotene plus photo(chemo)therapy. A significant difference in objective response rate was seen between bexarotene with a combination of photo(chemo)therapy (57.6%) and bexarotene without a combination of photo(chemo)therapy (25.5%, p < 0.001). Starting bexarotene at 300 mg/m² and combination with photo(chemo)therapy were detected as independent factors influencing response. Common treatment-related adverse events included hypothyroidism (85.8%), hypertriglyceridemia (68.5%), hypercholesterolemia (43.8%), and neutropenia (21.3%). Hypertriglyceridemia, hypercholesterolemia, and neutropenia occurred more frequently in patients who started with bexarotene at 300 mg/m² than patients who started with bexarotene at less than 300 mg/m² (hypertriglyceridemia, 76.4% vs. 57.0%, p = 0.001; hypercholesterolemia, 49.0% vs. 36.4%, p = 0.045; neutropenia, 28.0% vs. 12.1%, p = 0.002; respectively). The present study indicates that starting bexarotene at 300 mg/m² and combination of photo(chemo)therapy offer a promising efficacy for the treatment of patients with mycosis fungoides. Efficacy of low-dose bexarotene plus photo(chemo)therapy should be evaluated in future.

Topical and Systemic Formulation Options for Cutaneous T Cell Lymphomas

Although various anti-cutaneous T-cell lymphoma (CTCL) therapies are available for clinical use, appropriate chemotherapy lines for the treatment of CTCLs have yet to be established. Therefore, to date, various clinical trials for the treatment of advanced CTCLs are ongoing. In this review, we evaluate the therapeutic options that are available in clinical practice for treatment of early- and advanced-stage CTCLs (targeted therapies, histone deacetylase (HDAC) inhibitors, retinoids, interferons, cytotoxic drugs, etc.). We also examine clinical trials of novel regimens for the treatment of CTCLs.