Top-line success for Biocryst Pharmaceuticals Inc. in a phase IIa proof-of-concept trial called OPuS-1 (Oral ProphylaxiS-1) with oral kallikrein inhibitor BCX4161 against hereditary angioedema (HAE) brought competitor Dyax Corp. along for the ride, as backers of both companies guessed about what's in store for the busy therapeutic space.