FDA Names Potential FSHD Therapy GBC0905 an Orphan Drug to Speed Its Development

The U.S. Food and Drug Administration (FDA) has granted orphan drug status to GBC0905 as a potential treatment for facioscapulohumeral muscular dystrophy (FSHD),its developer, Genea Biocells, announced.

Orphan drug status aims to encourage therapies for rare and serious diseases, through benefits such as seven years of market exclusivity and exemption from FDA application fees.

GBC0905 is a highly selective small molecule, with a potent inhibitory action over a gene called double homeobox 4 (DUX4) in diseased skeletal muscle cells.

DUX4 was identified as a cause of FSHD. In adult muscle cells, DUX4 is normally “turned off.” But it becomes active in FSHD, and researchers believe that its activity influences that of other genes found in muscle cells, promoting muscle weakness and atrophy.

The mechanisms underlying this events, however, remain largely unknown.

In early studies, GBC0905 was seen to target DUX4-mediated mechanisms in muscle cells that contribute to cell death without affecting the formation of new muscle cells, a process called myogenesis.

“The FSHD field generally believes that blocking DUX4 will be curative. We are looking forward to thorough and expeditious development of this much-needed therapy,” Amanda Rickard, Genea Biocells’ lead scientist for its FSHD program, said in a press release.

GBC0905 is being developed for both types of FSHD, type 1 — the most common, approximately 95 percent of cases — and type 2, whose patients show a similar clinical symptoms as those with type 1 but carry a different genetic abnormality.

“We are very pleased that the FDA granted Orphan Drug Designation to GBC0905 as an accomplishment for our team and an important milestone in our journey toward bringing our lead product candidate to the clinic. We anticipate GBC0905 to be the first targeted therapy for patients suffering from FSHD, a relentless and debilitating disease,” said Uli Schmidt, president of Genea Biocells.

“The Orphan Drug Designation also validates our skeletal muscle technology which is a highly useful platform for modeling any number of other myogenic indications as we expand our pipeline,” Schmidt added.

Genea Biocells’ developed a technology platform that works to induce human pluripotent stem cells (hPSC) to convert into skeletal muscle cells. With this platform, scientists do not need to perform invasive biopsies on patients to retrieve these cells.

Researchers at Genea also developed a stem cell model of FSHD, which the company claims to be the world’s first to retain disease features of FSHD.