(Reuters) - PTC Therapeutics Inc said European regulators have given conditional approval to its muscle wasting disorder drug, sending its shares up 4.5 percent in early trading on Monday.
The approval is the first in the world for a drug designed to treat the underlying cause of Duchenne muscular dystrophy (DMD) - a genetic disorder that causes muscle degeneration and eventual death in boys.
Conditional marketing authorization of a drug allows for the marketing of medicines designed to treat life-threatening diseases that have few or no treatment options, even if comprehensive clinical data is not yet available.
As part of the conditional approval, PTC is obliged to complete a confirmatory late-stage trial of the drug, Translarna, and submit additional efficacy and safety data.
Translarna is designed to interact with a part of the cell known as a ribosome, enabling it to manufacture a protein called dystrophin, the absence of which causes muscle weakening in patients with DMD.
About 15 percent of DMD cases are caused by "nonsense mutations" that lead to a premature end to the translation of a gene into a protein, according to the U.S. National Institutes of Health.
The approval is for ambulatory patients aged five years and older.
PTC shares were up 3.4 percent at $28.74 in mid-morning trading on the Nasdaq.
(Reporting by Natalie Grover in Bangalore)