The biopharmaceutical company Ablynx and AbbVie have entered into a license agreement to develop and commercialize the anti-IL-6R Nanobody, ALX-0061, to treat inflammatory diseases. ALX-0061 is Ablynx's proprietary anti-IL-6R Nanobody that successfully completed a Phase IIA study in February 2013. Nanobodies are Ablynx’s proprietary class of therapeutic proteins based on single-domain antibody fragments. Under the agreement, Ablynx will be responsible for completing Phase II clinical development in rheumatord arthritis and systemic lupus erythematosus. Upon the achievement of predefined success criteria, AbbVie will exercise its right to in-license ALX-0061 and be responsible for subsequent Phase III clinical development and commercialization. Ablynx will retain an option for copromotion rights in Belgium, the Netherlands, and Luxembourg. Ablynx will receive an upfront payment of $175 million, which will partly be used to fund the next phases of clinical development of ALX-0061. Upon achievement of certain development, regulatory, commercial, and sales-based milestones, Ablynx will be eligible to receive additional milestone payments totaling up to $665 million as well as double-digit tiered royalties on net sales upon commercialization.