FDA grants marketing approval to VALCHLOR gel for cutaneous T-cell lymphoma

The FDA has granted marketing approval for mechlorethamine gel for the topical treatment of stage IA and IB mycosis fungoides-type cutaneous T-cell lymphoma in patients who have received prior skin-directed therapy, according to the drug manufacturer.

Mechlorethamine (VALCHLOR, Ceptaris) is a chemotherapeutic agent previously approved for IV treatment of mycosis fungoides. Before this approval, there were no FDA-approved topical mechlorethamine products — only non-standardized, pharmacy-compounded petroleum ointment or aqueous-based topical preparations.

Stuart R. Lessin

“The use of topical mechlorethamine has been documented over several decades, but this is the first time that a product has gone through the rigorous FDA approval process,” Stuart R. Lessin, MD, president of the board of directors of the Cutaneous Lymphoma Foundation and lead investigator in the VALCHLOR pivotal trial, said in a press release. “Not only is VALCHLOR manufactured under FDA’s good manufacturing practices, but it will also be accompanied by patient support and assistance programs which are not currently available with compounded mechlorethamine.”

Marketing approval for mechlorethamine was based on a randomized, observer-blinded, noninferiority pivotal trial comparing mechlorethamine with a pharmacy-compounded mechlorethamine preparation in patients with stage IA-IIA mycosis fungoides-type cutaneous T-cell lymphoma.

Patients (n=260) had received at least one prior skin-directed therapy, including topical corticosteroids, phototherapy, bexarotene (Targretin, Valeant Luxembourg) gel and topical nitrogen mustard (mechlorethamine).

Patients were not required to be refractory to or intolerant of prior therapies.

In the study, 60% of patients treated with mechlorethamine exhibited a confirmed response at 12 months, defined as decrease of at least 50% in the Composite Assessment of Index Lesion Severity (CAILS) score, whereas 48% of those treated with the compounded control achieved a confirmed response.

Complete responses comprised a minority of the CAILS overall response: Initial CAILS responses were observed at 1 month, with further responses seen through 11 months of treatment. In addition, no systemic absorption of mechlorethamine was detected with treatment.

“This is good news for patients and the treatment community,” said Youn H. Kim, MD, professor of dermatology and director of Multidisciplinary Cutaneous Lymphoma Clinic at Stanford University School of Medicine. “We now have the confidence of a FDA-approved product backed by evidence from a well-controlled clinical trial that demonstrated clinically meaningful responses in the majority of patients with stage IA and IB mycosis fungoides-type cutaneous T-cell lymphoma who have received prior skin-directed therapy.”