FDA approves injectable for subcutaneous use in adults with generalized myasthenia gravis

Halozyme Therapeutics announced that argenx received FDA approval for Vyvgart Hytrulo with Enhanze for subcutaneous use in adults with generalized myasthenia gravis who are anti-acetylcholine receptor antibody positive.

According to a Halozyme release, the injectable is a combination of human IgG1 antibody fragment efgartigimod alfa, marketed as Vyvgart, and recombinant human hyaluronidase PH20 (rHuPH20), the company’s Enhanze technology that improves subcutaneous delivery of biologics.

Vyvgart Hytrulo with Enhanze is to be administered subcutaneously by a health care professional as a 1,008 mg fixed dose, single injection over 30 to 90 seconds in once-weekly cycles for 4 weeks, per the release.

The product’s approval was based on positive results from the phase 3 ADAPT-SC study, in which Vyvgart Hytrulo reduced anti-AChR antibody levels comparable to IV Vyvgart in adult patients with generalized myasthenia gravis, the company stated. Results from the phase 3 ADAPT trial led to approval of IV Vyvgart in December 2021.

“We are pleased that argenx has received FDA approval for the subcutaneous form of efgartigimod, which reinforces their commitment to the patient community with a broadening of treatment options that brings flexibility for patients,” Helen Torley, MBChB, MRCP, president and CEO of Halozyme, said in the release. “We look forward to the multiple data readouts this year for subcutaneously administered efgartigimod in additional autoimmune conditions, with the potential to expand the number of approved indications and eligible patients.”