VALCHLOR® (mechlorethamine) gel is an alkylating drug indicated for the topical treatment of Stage IA and IB mycosis fungoides–type cutaneous T-cell lymphoma (MF-CTCL) in patients who have received prior skin-directed therapy

The MIDAS study:
Assessing the effect of triamcinolone on VALCHLOR-related skin irritation

Additional data not contained in the USPI

This information is being provided to help healthcare professionals when making assessments to improve patient care. This information is not contained in the FDA-approved label. Use of VALCHLOR with concomitant therapies has not been evaluated by the FDA. These data should not be interpreted as demonstrating better efficacy than what has been evaluated and approved in the product labeling.

At peak dermatitis (month 3), there was a significant reduction of contact dermatitis in lesions treated with VALCHLOR + triamcinolone compared to VALCHLOR alone1

Graph showing CAILS score during the study

Adapted from the SCORAD assessment tool, SCORD score determined the clinical severity of dermatitis by 1) assessing the percentage of total lesions that showed dermatitis, 2) measuring redness, swelling, oozing/crusting, scratch marks, skin thickening, and dryness on a 0-to-3 point scale, and 3) factoring in patients' self-reported current itch on a 0-to-10 point scale.1


Study design

MIDAS (mechlorethamine-induced dermatitis assessment study) was a prospective, randomized, open-label, self-controlled study at a single center among patients (n=28) with Stage IA/IB mycosis fungoides–type cutaneous T-cell lymphoma (MF-CTCL). Patients were required to have at least 2 similar lesions at least 8 cm2 in aggregate size. Lesions were separated into 2 groups for the 2 treatment arms, including separating by right and left side of the body when possible. All lesions were treated with topical 0.016% mechlorethamine gel once daily for 4 months. Half of these lesions were also treated with topical triamcinolone 0.1% ointment once daily for 4 months.1


Study limitations

MIDAS was not blinded, limited to one center, and only included a small number of patients who were willing to participate in the study per its structure. Patients were their own control; one patient mixed up the treatment arms from days 1 to 3 and was excluded from analysis except for intention to treat analysis. Use of an ultrapotent steroid or more frequent steroid dosing may have had a greater reduction in contact dermatitis.1

At month 3, less pruritis was also seen between treatment arms in patients with severe dermatitis (VASavg=2.03 vs VARavg=4.93; P<0.05)1

Using topical triamcinolone with VALCHLOR helped improve treatment-related skin irritation without compromising efficacy1

There was no negative impact on efficacy when co-administering triamcinolone with VALCHLOR1

Graph showing CAILS score during the study

This graph shows that the CAILS score was similar in both study arms.1 The efficacy of VALCHLOR was assessed in the original trial which is included in the USPI.2 The data from MIDAS has not been reviewed by the FDA and should not be interpreted as demonstrating better efficacy that what it in the product labeling.

CAILS TAC=CAILS score of VALCHLOR + triamcinolone; CAILS VAL=CAILS score of VALCHLOR alone; TAC=triamcinolone; VAS=visual analog scale.


VALCHLOR is a topical alkylating agent that targets rapidly proliferating T cells in the skin and is systemically undetectable1,2

Graph time point cell per million nucleated


In this study, a biopsy was obtained at baseline and at the end of treatment to assess the exploratory endpoint of response to therapy and molecular clonality. The investigators state that the molecular identity of the T-cell clones was identical in pre- and post-treatment sites. In each of the 2 study arms, the malignant clones were decreased at follow-up compared to the baseline skin biopsy.1

The graph above shows a representative patient who had 3 individual malignant clones identified at baseline. The patient had clinical response and an improved CAILS score with therapy.1

A correlation between reduction of malignant T cells and improved CAILS score has not been established.