ARGX: Takeaways from the R&D day

Research evidence excerpt

ARGX: Takeaways from the R&D day

USA | Biotechnology

Argenx EquityJuneResearch24, 2026

FLASH NOTEARGX: Takeaways from the R&D day

We attended ARGX’s Myositis R&D Day in person. We'll note: 1) For its Ph2, RATING BUY

mgmt disclosed that the IMNM subgroup achieved stat sig efficacy, while DM PRICE $853.40^

showed a clear signal, 2) ARGX changed its filing strategy - IMNM and DM will PRICE TARGET | % TO PT $1,013.00 | +19%

now be filed separately & co won't pursue PM. Based on mgmt’s comments 52W HIGH-LOW $934.62 - $510.06

& our illustrative analysis, we remain +'ve heading into Ph3 ALKIVIA readout in FLOAT (%) | ADV MM (USD) 93.0% | 296.56

IMNM & are cautiously optimistic that DM can hit stat sig in Ph3. MARKET CAP $56.6B

TICKER ARGX

Bottom line: ARGX's stock is down following its Myositis R&D Day, after mgmt disclosed a change ^Prior trading day's closing price unless otherwise noted.

in their filing strategy. Following FDA feedback, the co now plans to pursue approval for only IMNM

and DM (filing packages will be handled separately), with no current plans to file in PM.

On our end, we actually think the setup for ARGX has become more interesting heading into

the Ph3 in Q3'26: a) While expectations for DM have come down post-event, we remain cautiously

optimistic this pop could read out positively in Ph3 - our illustrative analysis suggests that Ph2 DM

pop had ~10pt TIS delta, which should be sufficient to hit stat sig in Ph3, b) More importantly, IMNM

alone represents a multi-billion-dollar opportunity w/ likely very rapid uptake.

.

To us, today's disclosures look like ARGX is taking an educated risk on the Ph3 readout. Rather Source: Jefferies analysis; Company data

than delaying the trial further to increase N & gain more clarity on subtype-specific effect sizes,