A small UK company acquired last year by Biogen has reported positive results from a study of a gene therapy for the treatment of a condition that causes blindness.
Biogen acquired Nightstar Therapeutics last year for US$800 million. One of the company's leading assets is for the treatment of retinitis pigmentosa. It is a rare inherited retinal disease, primarily affecting males, characterised by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene leading to a lack of active protein transport in photoreceptors. There are no approved treatments
The abnormality leads to the loss of the photoreceptor cells, resulting in retinal dysfunction by adolescence and early adulthood, progressing to legal blindness generally when patients reach their 40s.
The company has published in the journal Nature the results of the first-in-human dose-escalation clinical trial for a gene therapy to treat the condition.
In the study, all patients were back to baseline vision levels three months after the procedure, and seven of them had improved vision through six months of follow-up.
Biogen also secured another emerging gene therapy through its acquisition of Nightstar Therapeutics - NSR-REP1 for the treatment of choroideremia (CHM). CHM is a rare, degenerative, X-linked inherited retinal disorder, which leads to blindness, there are no approved treatments.
The genetic condition primarily affects males and is caused by loss of function in the CHM gene that encodes the Rab escort protein-1 (REP-1). The REP-1 protein plays a role in intracellular protein trafficking, and loss of function in the CHM gene leads to abnormal intracellular protein trafficking and impaired elimination of waste products from the retinal pigment epithelium and photoreceptors. Initially, patients with CHM experience poor night vision. Over time, the progressive visual loss ultimately leads to complete blindness.