CLE 400 Chronic Itch

Developing a novel topical drug to alleviate neuropathic itch


Clexio is developing CLE-400, a topical gel formulation containing a non-opioid, non-steroid, active compound, to alleviate neuropathic itch – chronic pruritus caused by nerve fiber damage, which is often underdiagnosed and has no approved treatment.

CLE-400 is a new investigational drug that has not been approved for commercial distribution.

Unmet need in the treatment of Neuropathic Itch

Between 23 and 44 million Americans are estimated to suffer from chronic pruritus. This condition can be debilitating, affects sleep and mood and can cause symptoms of anxiety and depression that can lead to a significantly reduced quality of life. Chronic pruritus is now known to be as debilitating as chronic pain and represents a serious public health concern§.

Neuropathic pruritus (or itch) is one of the types of chronic pruritus. Often underdiagnosed, it is caused by neuronal or glial damage along the sensory neural pathway. Neuropathic itch can be widespread or localized, and may be a debilitating condition associated with a markedly reduced quality of life.

Peripheral neuropathies that may involve neuropathic itch include Peripheral Diabetic Neuropathy, Post-herpetic Neuralgia, Small Fiber Neuropathy, Brachioradial pruritus and Notalgia paresthetica.

No therapies for neuropathic itch have been approved. In some cases, neuropathic itch can be very severe, and unfortunately there is a scarcity of effective treatments, underscoring that neuropathic itch is an important unmet clinical need**.

These conditions affect not only thousands of patients, but their families as well.

§Curr Derm Rep, Nicholas K. Mollanazar et al, 26 Jan 2015.
**Pain, J Hachisuka et al. March 2018; 159(3): 603–609

Our program

Scientific aspects

CLE-400 is a topical gel containing Detomidine, a potent α2-adrenergic receptor agonist.

We hypothesize that detomidine activates α2-adrenergic receptors on skin nociceptors, leading to inhibition of receptor excitability and attenuation of neural itch signaling.

CLE-400’s unique gel formulation enables maximal skin penetration while limiting systemic exposure. In addition, by creating a depot in the skin, CLE-400 is aimed at providing a long-lasting effect.

CLE-400, when administered topically, has shown effects in 3 different validated preclinical pharmacological models: Painful Peripheral Neuropathies, post-operative-pain and pruritus models. These studies each included placebo and positive controls. Rapid onset of effects was observed from day 1 of treatment and a cumulative analgesic effect was observed following repeated dosing.

Clinical aspects

CLE-400 has completed both its Single Ascending Dose and Multiple Ascending Dose Phase 1 clinical studies.

In addition, Clexio has initiated a Phase 2 Proof of Concept study, to assess the efficacy and safety of CLE-400 topical gel for the treatment of chronic pruritus in adults with Notalgia Paresthetica.
The study is a randomized, double-blind, vehicle controlled multicenter study, enrolling in the US.

For more information on this study, please visit:

* Patient voices throughout this website are paraphrased examples of typical experiences of people suffering from this disease.
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