Twin Phase 3 studies recruiting adults with lupus skin problems in US, Canada

Participants are actively being recruited for a pair of Phase 3 clinical trials testing enpatoran, an experimental oral medication designed to treat skin manifestations of lupus.

The identically designed ELOWEN studies aim to enroll more than 400 adults ages 18 to 75 with skin manifestations of lupus, with or without other disease symptoms. Participants in the trials will be randomly assigned to receive twice-daily enpatoran or a placebo, with the main goal of comparing how many patients experience a decrease of at least 70% in a disease severity score called the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI).

The ELOWEN-1 trial (NCT07332481) is currently recruiting at 11 sites in the U.S., while the ELOWEN-2 study (NCT07355218) is recruiting at 13 sites across the U.S. and Canada. Both studies are sponsored by enpatoran’s developer Merck KGaA, Darmstadt, Germany, which operates as EMD Serono in the U.S. and Canada.

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Targeting skin symptoms in lupus

Lupus is an autoimmune disease that can affect many systems throughout the body. In roughly 85% of patients, it affects the skin, and currently, there are no specific treatments approved specifically for skin manifestations of lupus. Enpatoran, also known as M5049, is designed to reduce lupus-related skin problems by blocking two inflammatory proteins, TLR7 and TLR8.

“For the 85% of lupus patients whose disease includes skin manifestations, often associated with substantial physical and psychosocial burden, the lack of targeted treatment makes the disease hard to control,” David Weinreich, MD, global head of R&D and chief medical officer for the healthcare business of Merck KGaA, said in a company press release.

In a previous Phase 2 trial called WILLOW (NCT05162586), various doses of enpatoran were tested against a placebo in lupus patients with skin involvement. Results from the study, published a few months ago, showed that enpatoran did not outperform the placebo at reducing measures of disease severity across the whole body, but it did improve skin involvement as measured by CLASI.

Based on the data from WILLOW, the U.S. Food and Drug Administration (FDA) recently granted enpatoran breakthrough therapy designation as a potential treatment for skin involvement in lupus. This designation is given to experimental therapies that have shown early promise as potential treatments for serious conditions with unmet medical needs; the designation aims to speed the development of important new medicines.

“This Breakthrough Therapy designation demonstrates that enpatoran has the potential to redefine how we approach lupus, by addressing the visible burden of rash, while potentially driving benefit beyond the skin. We look forward to working with the FDA to potentially bring this much-needed option to patients as quickly as possible,” Weinreich said.