OnabotulinumtoxinA as a promising treatment for primary trochlear headache: A retrospective case series.

OBJECTIVES: To report the efficacy of onabotulinumtoxinA (BoNTA) injections in relieving pain in patients with primary trochlear headache (PRTH). METHODS: Examination of medical records for patients diagnosed with PRTH according to the International Classification of Headache Disorders, 3rd edition criteria and treated with BoNTA. Data were collected for variables related to pain relief, duration of effectiveness, and adverse effects. RESULTS: Six patients were included in the study. All had previously undergone standard care interventions, including infiltrations or oral treatments, yet experienced treatment failure or symptom recurrence. All patients received 20 units of BoNTA, administered in the corrugator and procerus muscles. Subsequent to the BoNTA injections, all six patients reported substantial pain relief, with five achieving complete remission of symptoms. The analgesic effect persisted for a duration of 3 months. No adverse events were reported in any of the cases. CONCLUSIONS: Our case series presents the first evidence of the potential of BoNTA as a safe and effective treatment option for PRTH. From a clinical standpoint, having a safer alternative is of paramount significance for patients with limited treatment options, such as those with PRTH. Further research is warranted to validate these findings and explore the long-term efficacy of BoNTA in PRTH management.

Dual therapy with Erenumab and onabotulinumtoxinA: No synergistic effect in chronic migraine: A retrospective cohort study.

OBJECTIVE: To assess whether dual therapy with erenumab and onabotulinumtoxinA (BoNTA) was more effective than erenumab alone in chronic migraine. BACKGROUND: Calcitonin gene-related peptide (CGRP) is crucial in migraine. Erenumab binds to the canonical CGRP receptor in Aδ-fibers, and BoNTA prevents the release of CGRP from meningeal and extracranial C-fibers. It is still unknown whether dual therapy is more effective. METHODS: This was a retrospective study in a Headache Unit. There was a thorough revision of charts of patients receiving erenumab from December 2019 to March 2021. The cohort was divided into three groups according to BoNTA at the start of erenumab: (1) WBT: were on BoNTA and maintained it as dual therapy; (2) WoBT: were on BoNTA and discontinued; (3) NoBT: were not on BoNTA. Primary endpoint was reduction in monthly headache days (MHD) at 12 weeks. Secondary endpoints were percent improvement and ≥50% reduction in MHD. RESULTS: Of 237 charts reviewed, 187 met the inclusion criteria. Seventy-three (39%) were included in WBT, 44 (23.5%) in WoBT, and 70 (37.4%) in NoBT. The reduction in MHD was less with dual therapy [WBT 4.7 ± 7.68, WoBT 5.12 ± 7.98 (p = 0.80), NoBT 8.21 ± 7.84 p = 0.009]. The percentage of improvement was higher in the erenumab-alone group [NoBT 35%, WoBT 22.3% (p = 0.92), WBT 21.7% (p = 0.001)]. The probability of achieving a ≥ 50% reduction in MHD was lower in WBT than in WoBT (OR 0.66, p = 0.35) and in the NoBT group (OR 0.57, p = 0.14). CONCLUSIONS: Our findings suggest that dual therapy is less effective than erenumab alone. However, since the design has multiple limitations, further prospective studies are required to validate these data.