ZUG, SWITZERLAND -- Galderma (SIX: GALD), the pure-play dermatology category leader, announced the first patient enrollment for its phase II study investigating the efficacy and safety of nemolizumab in treating patients living with Chronic Pruritus of Unknown Origin (CPUO). The first patient of the trial - which is taking place in the United States - was enrolled at Dr. Vlada Groysman’s site in Birmingham, Alabama.

CPUO is an underdiagnosed condition defined as itch lasting for more than six weeks without an identified cause. It is a common condition and prevalent in nearly 30% of the elderly in certain populations, but despite its debilitating impact - with effects on sleep, mental health, and overall quality of life - there are currently no approved treatments.

Nemolizumab is a monoclonal antibody that specifically targets the IL-31 receptor alpha, inhibiting the signaling of IL-31, a neuroimmune cytokine that plays a key role in CPUO by driving itch, its main symptom.[1-4] This randomized, double-blind, placebo-controlled phase II study will determine the therapeutic potential of nemolizumab in adults with CPUO, to support progression to late-stage development.[8]

“We’re excited to launch this study exploring nemolizumab’s potential in patients with CPUO, many of whom have struggled for years without effective treatment options. Nemolizumab has shown outstanding efficacy in prurigo nodularis - a condition that shares important clinical and mechanistic features with CPUO - through its targeted inhibition of IL-31 signaling. With recent research further reinforcing IL-31 as a key driver of itch in CPUO, we’re hopeful that nemolizumab could offer meaningful relief to patients with this condition.”

DOCTOR SHAWN KWATRA, M.D.
LEAD INVESTIGATOR, CHRONIC PRURITUS OF UNKNOWN ORIGIN PHASE II STUDY

New data provides a better understanding of the key drivers of CPUO, underscoring the role of IL-31
Galderma’s study builds on a recent investigation into the causes of inflammation in CPUO, which uncovered critical insights into its complex inflammatory profile. The research - presented at the Society of Investigative Dermatology annual meeting in San Diego in May 2025 - found a significant increase in IL-31-producing CD4+ T cells in CPUO patients, reinforcing IL-31 as a key driver of the disease.[9] These results open the door to targeted therapies that address the root causes of CPUO, a disease with significant unmet needs that currently has no approved treatment options.

“The first patient enrollment in this study marks an important milestone in our commitment to advancing dermatology for every skin story - especially in areas of high unmet need. CPUO is a deeply distressing condition for patients, and the absence of approved treatments has left many without options. With nemolizumab’s targeted mechanism of action and promising results in related conditions, we’re hopeful this study will pave the way for a new therapeutic approach for those living with CPUO.”

BALDO SCASSELLATI SFORZOLINI, M.D., PH.D.
GLOBAL HEAD OF R&D
GALDERMA