Argenx SE: Taking a deeper look at efgartigimod in myositis ahead of phase 3 data in 3Q

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Argenx SE: Taking a deeper look at efgartigimod in myositis ahead of phase 3 data in 3Q

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Argenx SE

Taking a deeper look at efgartigimod in

myositis ahead of phase 3 data in 3Q

Maintain Rating: BUY | PO: 1,016.00 USD | Price: 806.03 USD

Each myositis subtype could be a $1bn opportunity 26 May 2026

We review the data available for efgartigimod in myositis and the overall landscape Equity

ahead of the topline ph 3 data expected in 3Q. Current SoC involves the use of steroids

and DMARDs, as well as IVIg and rituximab in more severe cases. Importantly, while IVIg Tazeen Ahmad Research Analyst

is approved for DM there are no therapies approved for ASyS or IMNM. High unmet need BofAS

remains due to lack of efficacy or poor tolerability. Efgar is being evaluated in DM, ASyS +1tazeen.ahmad@bofa.com646 855 4236

and IMNM. In ph 2, efgar showed encouraging signs of efficacy and safety across all Daniel Giraldo

subtypes. Given the high unmet need and lack of treatments available, particularly for Research Analyst

BofAS

ASyS and IMNM, we view myositis as an attractive commercial opportunity. We do not daniel.giraldoperez@bofa.com

break out value for myositis in our model but estimate each subtype could represent a Jeremiah Lorentz

~$1bn opportunity. ARGX is a 2026 top pick with a Buy with $1,016/€863 PO. Research Analyst

jeremiah.lorentz@bofa.com

Phase 2 data showed clinically meaningful improvements Wesley Yon

The phase 2/3 ALKIVIA trial enrolled 265 participants (89 in phase 2). The phase 3 Research Analyst

primary endpoint is the TIS (1-100 scale) at week 52. In phase 2, patients on wesley.yon@bofa.com

efgartigimod achieved a mean TIS improvement of 50.45 compared to 35.65 with Amy Qian

placebo at week 24 (2-sided p-val=0.0004).