MIGRAINE TREATMENTS: BUTORPHANOL TRANSNASALLY ADMINISTERED
Executive Summary
MIGRAINE TREATMENTS: BUTORPHANOL TRANSNASALLY ADMINISTERED is viable non-sedating way to alleviate migraine pain, National Headache Foundation Executive Director Seymour Diamond, MD, told a recent conference on new drug developments. He based his conclusion on a double-blind, double-dummy placebo study of migraine relief which compared transnasal butorphanol (Bristol's Stadol) to intramuscular methadone or a placebo in a group of patients normally requiring an injectable analgesic to ease migraine pain. The study, conducted at Chicago's Diamond Headache Clinic, used patients with moderate, severe or incapacitating migraine pain. The test subjects randomly were given either 10 mg of methadone, 1 mg of transnasally administered butorphanol or a placebo. Within the double-blind, double-dummy parameters of the study, those receiving Stadol got a repeat dose one hour later. The drug's onset of action was 15 minutes and it proved more effective overall than methadone and significantly more effective than the placebo, Diamond said. I.V. and intramuscular injection of butorphanol is recommended for the relief of moderate to severe pain. The synthetic opioid agonist-antagonist analgesic, when injected, has an onset time of about 10 minutes. One of the most frequent adverse reactions from I.V. or I.M. administration is sedation, which did not occur when the drug was given transnasally. The usual I.M. dose is 2 mg repeated every three to four hours, as necessary. Butorphanol is one of a number of compounds currently being studied for the treatment or prophylaxis of migraine pain, according to Diamond. Squibb's beta-blocker Corgard (nadolol) is awaiting FDA approval for migraine treatment. Another drug in development for both prevention and treatment is Glaxo's sumatriptan. Glaxo's 5HT[sub 1]-like receptor agonist is currently in Phase II trials in the U.S. for both prevention and treatment of migraines ("The Pink Sheet" March 6, T&G-2). "Several" clinical studies have shown the NSAID naproxen sodium (Syntex' Naproxen and Anaprox) to be an effective migraine treatment, Diamond said, adding that the "majority" of clinical trials for naproxyn as a migraine prophylaxis are still underway. The calcium channel blockers flunarizine, nimodipine and verapamil are other possible preventive agents, Diamond said. He made his comments at a May 5 conference on the NDA Pipeline sponsored by "The Pink Sheet" and International Business Communications. Flunarizine (Janssen's Sibelium) is in late clinicals for the treatment of migraine and epilepsy. An NDA submission is "two to three years away," according to Diamond. His clinic conducted one 24-week study using Sibelium as a prophylactic on 100 patients. Miles' nimodipine Nimotop was approved Dec. 28 with an indication for the treatment of post-cerebral aneurysm rupture. The Diamond Clinic conducted a study using nimodipine prophylactically for migraine and cluster headaches. "Although the results were promising for the migraine treatment indication, the company is not currently pursuing any active study into vascular headache prophylaxis," Diamond said. He remarked that the drug's price tag, about $ 8.45 per tablet, probably makes it prohibitive as a prophylactic. Several studies have indicated that the calcium channel blocker verapamil may prevent migraine by blocking transmembrane calcium exchange and because it has antiplatelet effects, Diamond said. The drug is not currently approved for migraine. Diamond also noted that the "gold standard" for migraine prophylaxis is the beta-blocker propanolol. However, the drug's frequency of dosage was considered a drawback by patients. With the availability of long-acting once-daily propanolol, the problem of patient compliance has been resolved, he commented.