Synageva Biopharma Corp., of Lexington, Mass., began dosing dosing with SBC-103 in patients with mucopolysaccharidosis IIIB, also known as Sanfilippo B syndrome, as part of a phase I/II study. The study will enroll about nine patients older than 2 years and younger than 12 with definitive diagnosis of MPS IIIB and developmental delay.