Applied Genetic Technologies Corp. (AGTC) dropped two pieces of bad news following Wednesday's market close. The Gainesville, Fla.-based company said it was halting development of rAAV2tYF-CB-hRS1, its adeno-associated virus (AAV)-based RS1 gene therapy for X-linked retinoschisis (XLRS), after top-line interim data from its phase I/II trial showed no sign of clinical activity at six months. AGTC also revealed that Biogen Inc. was walking away from their three-year-old, potential $1 billion collaboration and returning full rights to the clinical-stage XLRS and X-linked retinitis pigmentosa (XLRP) programs and discovery programs in adrenoleukodystrophy (ALD) and two ophthalmic targets, effective March 8, 2019.