Nektar Therapeutics announced data presentations from two Phase 1b, proof-of-concept studies of rezpegaldesleukin (also known as LY3471851 or NKTR-358) in patients with atopic dermatitis (AD) and plaque psoriasis at the 2022 European Academy of Dermatology and Venereology (EADV) Congress. Rezpegaldesleukin is a novel, first-in-class selective regulatory T-cell (Treg) inducing IL-2 conjugate in development to treat autoimmune and inflammatory conditions. It is designed to target the immune system imbalance that results from increased levels of inflammatory T cells and reduced numbers and impaired function of regulatory T cells (Tregs).

Decreased Treg numbers or impaired immunosuppressive function are known to contribute to the pathogenesis of multiple autoimmune and inflammatory diseases, including atopic dermatitis and psoriasis. Data are being presented at EADV from both a Phase 1b double-blind, randomized, placebo-controlled multiple-dose study evaluating the safety, tolerability, and pharmacokinetics of rezpegaldesleukin in patients with moderate-to-severe AD, as well as a Phase 1b double-blind, placebo-controlled study evaluating rezpegaldesleukin in patients with plaque psoriasis who are candidates for systemic therapy or phototherapy. Both studies were sponsored by Eli Lilly and Company.

Abstract P1611: "Efficacy and Safety of a Selective Regulatory T-Cell Inducing IL-2 Conjugate (LY3471851) in the Treatment of Psoriasis: A Phase 1 Randomised Study". The IL-2 conjugate Treg stimulator, LY3471851, showed a safety profile consistent with previous studies. In patients treated with LY3471851: Treg numbers increased; PASI, sPGA scores, and Itch NRS improved over the treatment period and PASI improvement was maintained after drug withdrawal up to Week 19.

Nektar entered into a strategic collaboration with Lilly in 2017 to develop and potentially commercialize rezpegaldesleukin (also known as NKTR-358). In partnership with Lilly, the Phase 2 program for rezpegaldesleukin includes the ongoing 280-patient Phase 2 study in lupus (NCT04433585), a second Phase 2 study planned to start in the first part of 2023 in atopic dermatitis and a third Phase 2 study being planned in a yet-to-be-announced autoimmune indication to potentially start in 2023. About Rezpegaldesleukin: Autoimmune and inflammatory diseases cause the immune system to mistakenly attack and damage healthy cells in a person's body.

A failure of the body's self-tolerance mechanisms enables the formation of the pathogenic T lymphocytes that conduct this attack. Rezpegaldesleukin is a potential first-in-class resolution therapeutic that may address this underlying immune system imbalance in people with many autoimmune and inflammatory conditions. It targets the interleukin-2 receptor complex in the body in order to stimulate proliferation of powerful inhibitory immune cells known as regulatory T cells.

By activating these cells, rezpegaldesleukin may act to bring the immune system back into balance. Rezpegaldesleukin is being developed as a self-administered injection for a number of autoimmune and inflammatory diseases.