argenx Doses First Subject in Study Evaluating Subcutaneous ARGX-113 for Autoimmune Diseases

The first participant has been dosed in a Phase 1 clinical trial evaluating  argenx‘s subcutaneous formulation of ARGX-113 in healthy volunteers.

ARGX-113 is an investigational antibody designed for the treatment of patients with severe autoimmune diseases associated with high levels of harmful immunoglobulin G (IgG) antibodies, such as myasthenia gravis (MG).

The open-label, non-controlled Phase 1 clinical trial will evaluate the pharmacokinetics (how the drug moves and behaves in the body), pharmacodynamics (the effect the drug has on the body), safety and tolerability of a subcutaneously administered formulation of ARGX-113 in up to 32 healthy participants.

The study’s goal is to compare the more convenient subcutaneous formulation’s effects with an intravenous formulation of ARGX-113 that’s being used in other clinical trials.

Myasthenia gravis is an autoimmune disease triggered by immunoglobulin G auto-antibodies, or IgGs. They attack critical signaling proteins at the junction between nerve and muscle cells. The attacks impair the signals, leading to muscle weakness.

“We are developing a subcutaneous formulation of ARGX-113 to offer greater convenience for patients with severe autoimmune conditions requiring long-term treatment,” Nicolas Leupin, chief medical officer of argenx, said in a press release. “This treatment option could represent a significant advancement over current standard of care in the treatment of these types of chronic diseases.

“In preclinical studies, we were highly encouraged to see that the subcutaneous formulation showed a similar PK [pharmacokinetics] and PD [pharmacodynamics] profile to that of the intravenous formulation,” Leupin said. “We look forward to comparing these healthy volunteer data with the preclinical data and data from our clinical trials.”

Other clinical trials evaluating intravenous formulations of ARGX-113 include a Phase 2 trial in MG (NCT02965573), for which topline data is expected to be announced in the first quarter of 2018. The main objectives of the trial are the determination of the safety, effectiveness, and pharmacological profile of ARGX-113 in patients with generalized muscle weakness.

In a previous Phase 1 clinical trial with healthy volunteers, the intravenous formulation was reported to be well-tolerated across multiple dosing regimens with beneficial pharmacodynamic effects relating to speed, depth and duration of IgG reduction.

The U.S. Food and Drug Administration granted orphan drug status to ARGX-113 in October 2017, following the publication on Aug. 31 of a quarterly update reporting the results of a Phase 2 trial evaluating ARGX-113 as a treatment for MG. Full results of the trial are expected in 2018.