June 13, 2019

New results from a clinical study with healthy volunteers found the investigational compound NKTR-358 safe and well-tolerated, providing support for testing it as a treatment for autoimmune diseases such as lupus.

Researchers have known that impaired production of interleukin-2 (IL-2) and dysfunctioning regulatory T cells called Tregs are key to breaking down the immune system’s tolerance to self, triggering autoimmune disease.  Treatment for autoimmunity has included IL-2 therapy at low doses, but these drugs are limited because they are effective for only a short time and also stimulate other types of T cells.  NKTR-358 is unique in that it stimulates only Tregs and is effective for a longer period of time.

In this blinded study there were no serious adverse effects at any dose of NKTR-358 among healthy volunteers. NKTR-358 was effective in increasing a specific type of Tregs that help regulate the immune system with minimal effects to conventional T cells or killer T cells which balance the immune response.

Investigators at Nektar Therapeutics and PRA Health Sciences concluded that further clinical testing of NKTR-358 is supported by these results which were reported at the 2019 European League Against Rheumatism (EULAR) annual meeting.