With Imaavy, J&J will go toe-to-toe with fellow Big Pharma AstraZeneca, which owns Soliris and Ultomiris.
Johnson & Johnson’s anti-FcRn antibody nipocalimab has been approved by the FDA to treat generalized myasthenia gravis. The drug will be marketed under the brand name Imaavy.
With the approval, J&J is poised to compete with the current major players in the generalized myasthenia gravis (gMG) space, including AstraZeneca, which owns the monoclonal antibodies Soliris and Ultomiris. J&J will also go up against Argenx’s Vyvgart and UCB’s Rystiggo and Zilbrysq. Like Imaavy, Vyvgart and Rystiggo are FcRn inhibitors—though they have a multi-year headstart. Vyvgart was approved in December 2021, while Rystiggo won the FDA’s go-ahead in June 2023.
Imaavy’s approval opens up its use in adults and teens aged 12 years and up who have tested positive for anti-acetylcholine receptor or anti-muscle-specific kinase antibodies, according to Wednesday’s announcement. David Lee, J&J’s Global Immunology Therapeutic Area head, in a prepared statement called the decision a “historic milestone” for patients with gMG and autoantibody diseases, noting that many of them have “few or no approved targeted treatments.”
The FDA’s verdict on Wednesday was backed by data from the ongoing Phase III Vivacity-MG3 trial. A readout in June 2024 showed that adding Imaavy to standard of care led to significant improvements in activities of daily living as compared with standard of care alone. J&J used a validated scale to measure such improvement and at the time reported that Imaavy-treated patients scored 4.70 points, whereas comparators hit 3.25 points.
“For someone living with gMG, a 1- to 2-point change on [the scale] may be the difference between normal eating and frequent choking on food, or shortness of breath at rest and being on a ventilator,” the pharma said at the time. Imaavy likewise improved the strength and function of different muscle groups.
Designed to be administered intravenously, Imaavy is a humanized IgG1 monoclonal antibody that targets the FcRn, a protein that helps antibodies—in the case of gMG, disease-causing ones that target healthy tissues—survive longer. Through this mechanism of action, Imaavy lowers the circulating levels of these auto-antibodies. J&J gained ownership of Imaavy from its $6.5 billion acquisition of Momenta Pharmaceuticals in August 2020.
Imaavy’s approval comes days after J&J narrowly beat consensus first-quarter earnings estimates, reporting sales of $21.9 billion in the quarter versus the analyst forecast of $21.63 billion. Imaavy could help the pharma weather declining sales of its immunology blockbuster Stelara, which in Q1 had a 34% year-on-year decline, reaching only $1.63 billion as compared with $2.45 billion during the same period the previous year.
