Applied Genetic Technologies Corp. and Biogen Inc. terminated a collaboration to develop gene-based therapies for inherited eye disorders following the failure of an early-stage study.

As a result, Applied Genetics will regain the full rights to the programs included in the July 2015 partnership which covers the development and commercialization of the company's portfolio of drug candidates intended to treat orphan diseases of the retina, including X-linked retinoschisis, X-linked retinitis pigmentosa and three other discovery programs.

X-linked retinoschisis, or XLRS, is a condition characterized by impaired vision that begins in childhood and occurs almost exclusively in males. X-linked retinitis pigmentosa, or XLRP, is an inherited condition that causes blindness in men due to mutation in the RPGR gene which is responsible for making a protein essential for normal vision.

The phase 1/2 study investigated rAAV2tYF-CB-hRS1 in patients with XLRS due to mutations in the RS1 gene which provides instructions for the production of the protein called retinoschisin and is found in the retina.

After six months of treatment, the drug was generally safe and well-tolerated but did not show any signs of clinical activity. Applied Genetic Technologies intends to halt the drug's development in XLRS once patient monitoring activities have been completed.

The Alachua, Fla.-based company said it will continue the ongoing clinical studies of rAAV2tYF-CB-hRS1 in patients with XLRP and achromatopsia, or color blindness.