Regeneron Pharmaceuticals and Eusa Pharma have been boosted by the news that regulators in the USA have approved a blindness drug and a leukaemia therapy, respectively.

First up, the US Food and Drug Administration has given the green light to Regeneron's Eylea (aflibercept) also known as VEGF Trap-Eye, for the treatment of patients with wet age-related macular degeneration. The approval, granted under a priority review, is based on two Phase III trials which showed that Eylea dosed every eight weeks, following three initial monthly injections, was clinically equivalent to the standard of care, Roche's Lucentis (ranibizumab injection) dosed every four weeks.

Regeneron quoted Jeffrey Heier of Tufts School of Medicine as saying that the approval "offers a much needed new treatment option for patients with wet AMD". He noted that Eylea achieved "the efficacy we've come to expect from current anti-VEGF agents, but with less frequent injections and no monitoring requirements. This may reduce the need for costly and time-consuming monthly office visits for patients and their caregivers".

Analysts believe the drug can be a blockbuster given its less frequent dosing compared with Lucentis.

Meantime, the FDA gave the thumbs-up to EUSA's orphan drug Erwinaze (asparaginase Erwinia chrysanthemi) for the treatment of acute lymphoblastic leukaemia (ALL) in patients with hypersensitivity to existing E coli-derived versions of the treatment.

ALL is the most common form of childhood cancer, with approximately 2,900 patients under the age of 20 diagnosed in the USA each year. It is also one of the most curable forms of cancer, Eusa noted, with remission rates in treated children of over 95% and 75 – 85% surviving at least five years without recurrence of leukaemia.

The company noted that it is the first approved treatment option available for patients with hypersensitivity to standard-of-care treatment with pegaspargase. An estimated 15%-20% of ALL patients develop hypersensitivity to E coli-derived asparaginase.

Chief executive Bryan Morton said that "launching Erwinaze to sit alongside our existing portfolio of specialty products is also a major strategic milestone for the company, as this is the first treatment Eusa has developed internally".