Argenx Surges as Potential Blockbuster Succeeds in Key Trial (1)

Argenx SE’s potential blockbuster Vyvgart drug helped people with a rare chronic inflammatory disease, kindling hopes that the medicine can alleviate a host of rare conditions and sending the shares up as much as 27%.

The drug succeeded in a trial for a neurological disorder that causes weakness in the arms and legs called chronic inflammatory demyelinating polyneuropathy or CIDP. The risk of patients relapsing was reduced by 61% compared with a placebo, the company said in a statement Monday.

Big Pharma is watching Argenx closely to determine whether Vyvgart, the first of a new class of medicines ...