Ophthotech Corp.'s potential $1 billion-plus, ex-U.S. deal with Novartis AG for Fovista, the antiplatelet-derived growth factor (PDGF) agent capable of enhancing the efficacy of anti-VEGF therapies in wet age-related macular degeneration (AMD), added juice to a growing $5 billion market – one about to take the next step into co-formulation.