Argenx announces positive CHMP Opinion for Vyvgart (efgartigimod alfa) subcutaneous injection for chronic inflammatory demyelinating polyneuropathy

Argenx SE announced the Committee for Medicinal Products for Human Use (CHMP) of the EMA has recommended European Commission (EC) approval of Vyvgart  1000mg (efgartigimod alfa) for subcutaneous (SC) injection as a monotherapy for the treatment of adult patients with progressive or relapsing active chronic inflammatory demyelinating polyneuropathy (CIDP) after prior treatment with corticosteroids or immunoglobulins.

The CHMP recommendation is based on positive results from the ADHERE clinical trial, the largest study of CIDP patients to date. In the ADHERE study, 66.5% (214/322) of patients treated with Vyvgart , regardless of prior treatment, demonstrated evidence of clinical improvement, including improvements in mobility, function and strength. ADHERE met its primary endpoint (p<0.0001) demonstrating a 61% reduction (HR: 0.39 95% CI: 0.25; 0.61) in the risk of relapse versus placebo. The study also demonstrated functional improvements across the Inflammatory Neuropathy Cause and Treatment (INCAT) disability scores (>1-point), grip strength (>17 kPa) and I-RODS scale (>8 points) at week 36 compared to baseline at entry to standard of care withdrawal phase. Almost all, 99% t of trial participants elected to participate in the ADHERE open-label extension. The safety results were generally consistent with the known safety profile of Vyvgart  in previous clinical studies.

The ADHERE trial was a multicenter, randomized, double-blind, placebo-controlled trial evaluating SC efgartigimod alfa for the treatment of chronic inflammatory demyelinating polyneuropathy (CIDP). ADHERE enrolled 322 adult patients with CIDP, 130 of whom were based in Europe, who were off treatment (not on active treatment within the past six months or newly diagnosed) or being treated with immunoglobulin therapy or corticosteroids. The trial consisted of an open-label Stage A followed by a randomized, placebo-controlled Stage B. In order to be eligible for the trial, the diagnosis of CIDP was confirmed by an independent panel of experts. Patients entered a run-in stage, where any ongoing CIDP treatment was stopped and in order to be eligible for Stage A had to demonstrate active disease, with clinically meaningful worsening on at least one CIDP clinical assessment tool, including INCAT, I-RODS, or mean grip strength. Treatment naïve patients were able to skip the run-in period with proof of recent worsening. To advance to Stage B, patients needed to demonstrate evidence of clinical improvement (ECI) with SC efgartigimod alfa. ECI was achieved through improvement of the INCAT score, or improvement on I- RODS or mean grip strength if those scales had demonstrated worsening during the run-in period. In Stage B, patients were randomized to either SC efgartigimod alfa or placebo for up to 48 weeks. The primary endpoint was measured once 88 total relapses or events were achieved in Stage B and was based on the hazard ratio for the time to first adjusted INCAT deterioration (i.e. relapse). After Stage B, all patients had the option to roll-over to an open-label extension study to receive SC efgartigimod alfa.

“Our mission is to develop innovative, targeted treatments for patients with rare and severe autoimmune diseases, who continue to face significant unmet needs. The positive CHMP opinion for VYVGART in CIDP brings us one step closer to providing patients across Europe with a transformational new treatment option that provides meaningful functional improvement,” said Dr. Luc Truyen , Chief Medical Officer, argenx.  “VYVGART is the first and only targeted IgG Fc-antibody fragment for CIDP and if approved, would mark the first treatment in Europe with a novel, precision mechanism of action for CIDP patients in 30 years.”

“For the patient population represented by the European Patient Organisation for Dysimmune and Inflammatory Neuropathies (EPODIN) and for those affected by CIDP, this is excellent news,” said Jean-Philippe Plançon, President of EPODIN. “There are still considerable unmet medical needs in the management of CIDP, and the CHMP’s recommendation brings renewed hope for improved treatment options and quality of life.”