The first gene therapy approved in the United States made a significant step toward winning approval in Europe as well as the European drug regulator’s expert committee adopted a positive opinion for its approval.

Swiss drugmaker Novartis and Philadelphia-based Spark Therapeutics said Friday that the European Medicines Agency’s Committee for Medicinal Products for Human Use, or CHMP, issued a positive opinion on EMA approval for Luxturna (voretigene naparvovec). A gene therapy developed and marketed in the US by Spark Therapeutics, Luxturna treats biallelic RPE65 mutation-associated retinal dystrophy, a rare genetic disorder that, if left untreated, leads to blindness. The US Food and Drug Administration approved Luxturna, an adeno-associated viral vector-based gene therapy, in December of last year. A European Commission marketing authorization decision is anticipated within approximately two months of the positive CHMP opinion.

Under an agreement between the two companies, Novartis is marketing Luxturna in markets outside the US. Based in London, but planning to relocate to Amsterdam following the UK’s exit from the European Union, the EMA regulates drugs across the European Union and the European Economic Area, the latter of which includes Norway, Iceland and Liechtenstein. However, Switzerland has its own regulatory agency, Swissmedic.

An investment analyst note by B. Riley FBR noted that Luxturna’s downstream approval will trigger a $25 million milestone payment from Novartis to Spark. However, it also pointed to key challenges facing Luxturna, including the need for reimbursement arrangements in individual European countries, difficulty capturing patients with RPE65 retinitis pigmentosa and competition from another AAV-based gene therapy from MeiraGTx, which is running a Phase I/II trial program and may siphon off patients from Luxturna.

In addition, the report stated that the bigger catalyst for Spark is data expected at the end of this year for SPK-8011, its AAV-based gene therapy for hemophilia A. The report thus gave Spark’s stock a neutral rating. Shares of Spark, which trades on the NASDAQ under the ticker symbol ONCE, were down 1.64 percent in late-morning trading following the news of the CHMP decision.

Data for SPK-8011 at the end of the year would likely mean a presentation at the American Society of Hematology’s annual meeting, which will take place in December in San Diego.

Photo: Yukiko Matsuoka, Flickr