Sarepta Therapeutics expanded into limb-girdle muscular dystrophy last May, when it ponied up $60 million to license five gene therapies and snag an option to acquire the company. Now, it's buying Myonexus and its pipeline outright for $165 million.
“The five LGMD gene therapies being developed fit brilliantly with Sarepta’s mission to develop therapies with the potential to rescue the lives of patients with serious life-limiting rare genetic diseases,” said Sarepta CEO Doug Ingram in a statement. “Our confidence in these programs has come from the fact that our micro-dystrophin gene therapy and the Myonexus programs have much in common, including inventors from Nationwide Children’s Hospital, a shared vector in AAVrh74 and, to date, similar pre-clinical safety data.”
Three of the five limb-girdle muscular dystrophy (LGMD) programs are in clinical development. The remaining two are still preclinical, but ready to move into the clinic, Sarepta said.
The company presented early data for one of the programs, AAVrh74.MHCK7.micro-Dystrophin, now called SRP-9001, last June. The treatment, delivered using an adeno-associated virus (AAV) vector, uses microdystrophin rather than dystrophin as the latter is too big to fit into the vector. The data, taken from three patients, showed the patients had "robust levels" of microdystrophin, producing 38% of the protein compared to normal. The company announced updated data from three LGMD patients on Wednesday showing that the mean protein expression was 51% and that all three patients had a "striking decrease" in their level of serum creatine kinase (CK), a biomarker linked to muscle damage.
RELATED: BIO: Lightning round with Sarepta's Doug Ingram
After seeing Exondys 51 through FDA approval for a subset of patients with Duchenne muscular dystrophy, Sarepta started building its gene therapy stable. Exondys 51 only works for patients whose disease is amenable to exon 51 skipping—about 13% of people with DMD. Unlike Exondys 51 and its peers, gene therapies are “agnostic to mutations,” and could be used to treat everyone with DMD, Ingram told FierceBiotech in a previous interview.
The company is working on DMD gene therapies in-house and has added to its pipeline through various licensing deals with the likes of Nationwide, Genethon, Lysogene, Lacerta and Myonexus. Those deals have added a number of indications to Sarepta’s pipeline; in addition to LGMD, the company has picked up gene therapies for Sanfilippo syndrome and Pompe disease, as well as a couple of rare central nervous system diseases.
The biotech was up 6% in midmorning trading.
Editor's note: This story has been updated to clarify that the updated data are from three patients with Limb-Girdle muscular dystrophy and not Duchenne muscular dystrophy.