This week, the New England Journal of Medicine published data from the ADAGIO Phase 3 clinical trial of Israeli drugmaker Teva’s Azilect (rasagiline). The trial was designed to test whether Azilect, which is already approved for symptomatic treatment of Parkinson’s, may also have a disease-modifying effect.

For early-stage PD patients, a 1-milligram dose of Azilect met all three clinical endpoints for disease modification. However, a 2-milligram dosage met only two of three endpoints. Because of this inconsistency, we cannot definitively conclude that the drug has disease-modifying effects, but the results are intriguing and possibly exciting nonetheless. The Michael J. Fox Foundation spoke with Karl Kieburtz, MD, MPH, about how patients should interpret the news.