Efgartigimod - (ALKIVIA)

August 17, 2026: Zai Lab (NASDAQ: ZLAB; HKEX: 9688) and argenx (NASDAQ/Euronext: ARGX) reported positive topline Phase 3 ALKIVIA results for VYVGART Hytrulo (efgartigimod alfa and hyaluronidase-qvfc) in adults with autoimmune myositis.

The study met its primary endpoint in the combined immune-mediated necrotizing myopathy (IMNM) and dermatomyositis (DM) population: mean Total Improvement Score at Week 52 improved by 15.4 points versus placebo (47.95 vs 32.56; p=0.0011). Benefit emerged by Week 4 and was sustained through 52 weeks despite steroid tapering.

In prespecified subtype analyses, IMNM met the primary endpoint with a 14.8-point improvement over placebo (45.05 vs 30.24; p=0.0048). In DM, improvement was 14.5 points (51.51 vs 36.96), but statistical significance was not reached (p=0.1093). All six TIS core measures favored efgartigimod; DM patients also showed improvement in skin disease activity. Safety was consistent with prior studies and the known efgartigimod profile.

ALKIVIA was a global randomized, double-blind, placebo-controlled Phase 2/3 study; Phase 3 enrolled 175 patients within a total 264-patient trial. Detailed results will be presented at an upcoming medical meeting.