Immunovant stakes claim for FcRn niche, posting midphase Graves’ data and plotting next steps

Immunovant has advanced its mission to claim an unoccupied area of the competitive anti-FcRn space, reporting phase 2 data that support its attempt to be the first to market in Graves’ disease. 

The potential for FcRn inhibition to improve outcomes across a laundry list of autoimmune diseases that are driven by IgG autoantibodies has attracted argenx, Johnson & Johnson and UCB. As those companies have worked to carve up the market, Immunovant, a biotech in the Roivant stable, has identified Graves’ as an indication it may be able to call its own, at least for a while.

Immunovant posted phase 2 data in the indication after the market closed Wednesday. In the 24-week, open-label trial, the response rate in the initial cohort of recipients of batoclimab “meaningfully exceeded 50%.” The biotech called the rate of normalization of T3 and T4 hormone levels “encouraging” because patients are unlikely to spontaneously improve.

The ongoing study is enrolling people who are hyperthyroid, a state caused by Graves’, despite treatment with an antithyroid medication for more than 12 weeks. Participants are receiving 680 mg of batoclimab subcutaneously once a week for 12 weeks, followed by 340 mg of the same molecule subcutaneously once a week for another 12 weeks.

Immunovant linked the higher dose to a mean IgG reduction of 81% after 12 weeks of treatment, a result it called best in class. The reduction was smaller on the lower dose, and the biotech saw a similar dose response in the data on changes in anti-TSHR autoantibodies. Improvements in a range of clinical outcomes were numerically higher on the 680mg dose too.

While talking up the data on batoclimab, Immunovant CEO Pete Salzmann, M.D., said the biotech intends to focus “future development in Graves’ on IMVT-1402, with plans expected to be announced later in 2024.” 

IMVT-1402 is another anti-FcRn drug candidate that is designed to match batoclimab’s effect on IgG antibodies while avoiding its impact on albumin and LDL cholesterol. Early evidence that the molecule meets that brief sent Immunovant’s stock skyward earlier this year and led the biotech to start working to initiate a broad set of pivotal trials in 2024.

Shares in Immunovant climbed 11% to $40.33 in premarket trading from a Wednesday closing price of $36.18.