Shares of ImmunoCellular Therapeutics Ltd. gave back some gains on Wednesday following a run-up on news that European regulators granted special status to its experimental brain cancer drug.

The Woodland Hills biotech received an “orphan” designation for its ICT-107, a drug that treats glioblastoma, one of the most common and fast-developing types of brain tumor.

Orphan drugs target either rare or particularly hard-to-treat diseases that ordinarily would not be financially worth pursuing. The European Medicines Agency grants orphan drug developers a variety of incentives, including a 10-year period of market exclusivity, a streamlined review process, fee reductions, tax incentives and access to scientific advice during product development.

ImmunoCellular previously received U.S. Food and Drug Administration orphan designation for ICT-107, with similar incentives, in the U.S. market.

Shares lost 7 cents, or about 5 percent, to close at $1.31 on the NYSE Markets. Shares had gained 14 percent on Tuesday.