Sarepata Soars As Investors Cheer DMD Drug's Progress

(RTTNews) - Shares of Sarepta Therapeutics Inc. (SRPT) are up in pre-market trading on Wednesday as investors welcome the news of the company's progress made in the NDA submission for Eteplirsen.

Eteplirsen is Sarepta's lead drug candidate for Duchenne Muscular Dystrophy, one of the most common fatal genetic disorders, caused by a mutation in a gene that encodes for a structural protein in muscle called dystrophin. Eteplirsen is designed to work by skipping exon 51 in the dystrophin gene to correct for specific genetic mutations and restore the gene's ability to make a functional, though shorter, form of the dystrophin protein.

The company had originally planned to submit a NDA for the approval of Eteplirsen by the end of 2014 under a potential Accelerated Approval pathway based on encouraging long-term clinical data from a phase IIb study.

However, last September, the FDA notified Sarepta that additional data were required as part of the NDA submission, including more specific data on a minimum duration of safety in new patients exposed to Eteplirsen.

Accordingly, last November, the company initiated an open-label study of Eteplirsen in non-ambulant patients with DMD and another open-label confirmatory study of Eteplirsen in ambulant patients with DMD. Taking into account the data requests and additional FDA discussions, the company later planned for an NDA submission by mid-year 2015.

Sarepta, which held a pre-New Drug Application meeting with the FDA regarding Eteplirsen yesterday, has agreed with the regulatory agency to initiate a rolling NDA submission and will submit the non-clinical and CMC components of the NDA by the end of this week. As previously announced, Sarepta plans to submit the final component of the NDA by mid-year 2015.

There is currently no approved therapy in the United States for DMD.

BioMarin Pharmaceutical Inc. (BMRN) , PTC Therapeutics (PTCT) and Santhera Pharmaceuticals Holding AG, which trades on the SIX Swiss Exchange, are the other companies that are involved in developing therapies for the treatment of Duchenne Muscular Dystrophy.

BioMarin's investigational drug for DMD is known as Drisapersen. It also works by the same mechanism as that of Sarepta's Eteplirsen as it induces the skipping of dystrophin exon 51. Developed by Prosensa Holding N.V., Drisapersen came under BioMarin's fold when BioMarin acquired Prosensa last November.

The process of rolling NDA submission to the FDA for Drisapersen, which began last October, was completed in April of this year.

BioMarin plans to file for EU approval of Drisapersen this summer.

PTC Therapeutics' DMD drug is known as Translarna, and it targets a different sub-population in DMD compared to exon skipping therapies.

Drisapersen received "conditional approval" in the European Union for the treatment of nonsense mutation Duchenne muscular dystrophy in August 2014, and was launched in Germany last December, which marked the first launch in the EU. Since then, PTC Therapeutics has grown its commercial footprint of Translarna to approximately 25 countries to date.

In the U.S., the rolling submission of a NDA for Translarna for the treatment of nonsense mutation Duchenne muscular dystrophy commenced last December. A phase III trial, which forms the basis for finalizing the NDA submission, is underway, and top-line data are expected in the fourth quarter of this year.

Santhera Pharmaceuticals' DMD drug candidate is known as Idebenone. The company reported positive results from a phase III trial of Idebenone in patients with Duchenne Muscular Dystrophy in May 2014. Preparations are underway to file for regulatory approvals for Idebenone in the US and EU.

According to research and consulting firm GlobalData, the worldwide market for Duchenne Muscular Dystrophy therapies is estimated to record an impressive Compound Annual Growth Rate of 160.5%, from approximately $8.2 million in 2014 to $990 million by 2019.

We had alerted our premium subscribers to SRPT on March 12, 2012 when it was trading around $6.60. The stock, which touched an all time high of $55.61 on October 7, 2013, has given back most of its gains. SRPT closed Tuesday's trading at $16.38 and is up 44% in today's pre-market trading.

PTCT was one of our stock picks in February 2014 and it was trading around $29 then. Having touched an all-time high of $76.64 on March 13, 2015, the stock trades around $51.