Anti–calcitonin gene-related peptide (anti-CGRP) monoclonal antibodies are effective for patients with chronic migraine and medication overuse headache regardless of detoxification strategy, according to investigators.
Abruptly discontinuing overused analgesics with health care provider oversight – a frequently resource-intensive and challenging process – is no more effective for controlling medication overuse headache than simply advising patients to stop, reported lead author Umberto Pensato, MD, of the University of Bologna, Italy, and colleagues.
“[C]urrently, the abrupt discontinuation of the overused painkiller(s), accompanied by the start of a pharmacological preventive therapy, is the most recommended strategy [for medication overuse headache],” the investigators wrote in Cephalalgia. “While painkiller(s) withdrawal could be accomplished on an outpatient basis in most cases, an in-hospital setting may be required to achieve successful discontinuation in a subgroup of patients with medication overuse headache, further weighing on individual and hospital costs. Additionally hampering this approach, the abrupt discontinuation of the overused painkiller(s) invariably results in disabling withdrawal symptoms for up to 2 weeks, including a transitory worsening of headache, the so-called ‘rebound headache.’”
Inpatient or outpatient: Does it matter?
According to Pensato and colleagues, early evidence suggests that previous painkiller withdrawal does not impact the efficacy of anti-CGRPs for medication overuse headache, yet relevant data remain scarce. To address this knowledge gap, they conducted a prospective, real-world study exploring the relationship between detoxification and outcomes after starting anti-CGRP therapy.
Out of 401 patients enrolled based on initiation of erenumab or galcanezumab, 111 satisfied inclusion criteria, including diagnosis of chronic migraine and medication overuse headache, at least 28 days of analgesic usage and headache days per month in the preceding 3 months, and other factors. Of these 111 patients, 83 underwent in-hospital detox, while the remaining 28 patients, who declined detox based on personal reasons or COVID-19–related bed shortage, were advised to discontinue overused medication on an outpatient basis (without oversight).
The primary endpoint was medication overuse headache responder rate after 3 months, as defined by ICHD-3 diagnostic criteria. Secondary endpoints included 6-item headache impact test (HIT-6), monthly headache days (MHD), migraine disability assessment score (MIDAS), mean pain intensity (MPI), monthly pain medication intake (MPMI), baseline predictors of response/refractoriness, and safety.
Three months after starting anti-CGRP therapy, 59% of patients had resolution of medication overuse headache, including 57% in the inpatient detox group and 64% in the outpatient group, a difference that was not statistically significant (P = .4788). Approximately half of the patients (51%) had at least 50% reduction in monthly headache days; although the rate was numerically lower in the inpatient group compared with the outpatient group, the difference was again not significant (51% vs. 54%; P = .8393).
“Our results support the emerging evidence that anti-CGRP drugs may be effective in these patients irrespective of the detoxification program,” the investigators concluded. “Further studies are needed to definitively confirm these results, potentially leading to a paradigm shift in the management of medication overuse headache.”
Abrupt or gradual detox?
According to Alan M. Rapoport, MD, clinical professor of neurology at the University of California, Los Angeles, and editor-in-chief of Neurology Reviews, the study was hampered by two major design limitations.
“The biggest problem I see is that the two groups were treated very differently for their detoxification,” Rapoport said. “One group was detoxified abruptly in the hospital, so the authors were sure that the patients were off acute-care medication before they started their preventives. The other group was advised to stop their medication on an outpatient basis. The issue is that we have no follow-up as to whether the outpatients did or did not abruptly detoxify. A bigger issue was that the two groups were not randomized so there are many other variables that may have come into consideration.”
Still, Rapoport, a past president of the International Headache Society (IHS), noted that the findings strengthen a growing body of evidence supporting the efficacy of monoclonal antibodies for medication overuse headache regardless of detoxification strategy. He cited a 2020 studyby Carlsen and colleagues conducted at the Danish Headache Center in Copenhagen, which reported similar medication overuse headache outcomes across three randomized cohorts whether they received preventive therapy with detoxification, preventive therapy without detoxification, or detoxification followed 2 months later by preventive therapy.
“What I have noticed since we have had monoclonal antibodies in our armamentarium is that these drugs work very well even when the patient has not fully detoxified,” Rapoport said. “What I do with my patients is not teach them how to detoxify now, but simply educate them to take fewer acute care medications as their headaches get better from the monoclonal antibodies; they should try to take fewer acute care medications for milder, shorter headaches, and just let them go away on their own. Previous research suggests that even when a patient is not educated at all about medication overuse headache and the reason for detoxification, monoclonal antibodies still work in the presence of medication overuse headache, and improve it.”
The investigators disclosed relationships with Allergan, Novartis, Teva, and others. Rapoport is on the speakers bureau for AbbVie.
This story originally appeared on MDedge.com, part of the Medscape Professional Network.
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