U.S. health officials said there may be more than one cause to the outbreak of the mysterious lung illness linked to e-cigarette use, and said they do not see a meaningful drop in new cases.

The number of Americans sickened by a severe vaping-related illness continues to increase, according to a U.S. health official speaking at a Congressional hearing.

GW Pharmaceuticals’ marijuana-based treatment Epidyolex won a positive recommendation for marketing approval from a European Medicines Agency (EMA) panel for use as an additional treatment for two types of seizures.

U.S.-listed shares of GW Pharmaceuticals rose 8 percent as the company’s marijuana-based treatment Epidiolex cleared the last hurdle after the Drug Enforcement Administration labeled the drug as having a low abuse potential.