Serious AEs were reported for 8 (20%) patients overall (GDNF/GDNF: 7, placebo/GDNF: 1), and were all judged to be unrelated to study medication: device-related events (3), traumatic muscle rupture (1), menorrhagia requiring hysterectomy and postoperative infection (1), multifactorial confusion and fluctuating cognition (1), recurrence of pre-study depression and paranoia (1), and osteoarthritis (1). The gene discussed is GDNF; the disease is major depressive disorder.