The label is weird. As far as I know, C1-Inhibitor concentrate is an effective therapy that rapidly relieves acute swelling attacks at any body location in patients with HAE. Makes sense the FDA wants 2 products in the market but I don't have a clue regarding the narrow label.
Edit: Found the reason to the weird label- Inclusion Criteriain CLS phase III trial
* Documented congenital C1-INH deficiency * Acute facial or abdominal HAE attack