May 15 (Reuters) - Eli Lilly and Co said on Tuesday that patients with episodic cluster headache attacks had reduced symptoms when treated with its experimental migraine drug galcanezumab compared to those treated with a placebo.
However, Lilly said a second trial for patients with chronic cluster headache attacks failed.
Patients with episodic cluster headache treated with a 300 mg dose of galcanezumab experienced an average of 8.7 fewer headache attacks per week over a three-week period. Those receiving placebo reported 5.2 fewer attacks per week, it said.
Patients who participated in the trial had a baseline average of 17.5 cluster headache attacks per week. Cluster headaches are recurring, intense headaches that can occur several times daily during a "cluster period."
Galcanezumab targets a protein associated with pain signaling called calcitonin gene-related peptide (CGRP). Lilly's drug is part of a new class of drugs targeting CGRP in order to treat migraines being developed by companies including Amgen Inc , Teva and Allergan.
Lilly has already reported positive migraine data for galcanezumab, and expects a decision by the U.S. Food and Drug Administration by the third quarter 2018.
Amgen Inc's Aimovig is likely to be the first drug in the class approved, with a decision expected by the FDA later this week.
Lilly said an estimated 85-90 percent of cluster headache cases are "episodic" with attacks occurring in periods that last from seven days to one year, with pain-free remission periods of one month or longer. The rest are classified as "chronic" with attacks occurring for more than a year without a remission period, or with remission lasting less than a month. (Reporting by Michael Erman in New York; Editing by Gopakumar Warrier)