Argenx boosts pipeline with new version of lead drug

Argenx has the first data on a new subcutaneous formulation of its rare autoimmune disease drug efgartigimod that could make it a much more patient-friendly prospect.

The company already has an intravenous formulation of efgartigimod (ARGX-113) in trials for myasthenia gravis (MG), immune thrombocytopenia (ITP) and pemphigus vulgaris (PV), all of which are characterized by high levels of pathogenic immunoglobulin G antibodies. Now, Argenx has data showing that its subcutaneous formulation behaves in the same way as the IV version in the body, and seems to be equally effective at depleting IgG levels.

The results raise the hope that the antibody fragment-based drug could be delivered via an IV loading dose to begin with, and then given by simple injection—potentially by the patient at home—as a maintenance therapy.

That would provide “flexible dosing options and greater convenience for patients with severe auto-immune conditions requiring long-term treatment,” according to Argenx’s recently appointed COO Keith Woods, who said the new formulation has now been added to its product pipeline. “With an SC formulation, we also plan to explore the potential for an off-the-shelf delivery system using a fine bore needle size to allow patients additional optionality around administration,” he added.

The Belgian-Dutch biotech has been on a roll over the last few months, completing an impressive $115 million IPO on the Nasdaq, following that up with a $231 million additional offering as 2017 drew to a close, and reporting positive results for IV efgartigimod in MG. If approved, it would compete with big-selling drugs such as Alexion’s $3 billion blockbuster Soliris (eculizumab) in MG, but with a differentiated mechanism of action.

In that study, the drug achieved a clinically significant improvement in symptoms (muscle weakness) in 75% of patients, compared to 25% of the placebo group. Last week, the biotech said it had completed an end-of-study meeting with the FDA and is designing a pivotal, phase 3 trial that should get underway before the end of the year. And it’s also waiting for readouts from phase 2 trials of efgartigimod in ITP and PV in the second half.

Argenx also has a second R&D track focusing on cancer, headed by CD70 antagonist ARG-110 for patients newly diagnosed with acute myeloid leukemia (AML) which has progressed to phase 2 as a combination with widely used AML chemotherapeutic drug azacytidine, phase 1 candidate ARGX-111 for cancer metastases, and AbbVie-partnered cancer immunotherapy ARGX-115.

Source: FierceBiotech