Cambridge, Mass.-based Alnylam Pharmaceuticals Inc. said its drug lumasiran was granted accelerated assessment under the European Medicines Agency's priority medicines scheme to treat kidney and urinary tract disease.

The EU agency granted lumasiran the designation for treating Primary Hyperoxaluria Type 1, a disease in which crystals build up in the kidneys and urinary tract. The illness results in pain due to kidney stones.

Alnylam said the designation was based on results from the ongoing phase 1/2 study of the drug.

The regulator grants the designation to enhance support for medicines that address an unmet medical need and where early clinical data show the potential to benefit patients.

Alnylam plans to advance the drug to a phase 3 study in the latter part of 2018.

Lumasiran was previously granted breakthrough therapy designation by the U.S. Food and Drug Administration.

Meanwhile, Sanofi previously decided against exercising an option to develop lumasiran under a rare disease collaboration agreed upon in January 2014.