Pharmacokinetic Variability of Drugs Used for Prophylactic Treatment of Migraine

Consensus of the Brazilian Headache Society (SBCe) for the Prophylactic Treatment of Episodic Migraine: part I

The Brazilian Headache Society (Sociedade Brasileira de Cefaleia, SBCe, in Portuguese) nominated a Committee of Authors with the aim of establishing a consensus with recommendations regarding prophylactic treatment for episodic migraine based on articles published in the worldwide literature, as well as personal experience. Migraine affects 1 billion people around the world and more than 30 million Brazilians. In addition, it is an underdiagnosed and undertreated disorder. It is well known within the medical community of neurologists, and especially among headache specialists, that there is a need to disseminate knowledge about prophylactic treatment for migraine. For this purpose, together with the need for drug updates and to expand knowledge of the disease itself (frequency, intensity, duration, impact and perhaps the progression of migraine), this Consensus was developed, following a full online methodology, by 12 groups who reviewed and wrote about the pharmacological categories of the drugs used and, at the end of the process, met to read and establish conclusions for this document. The drug classes studied were: anticonvulsants, tricyclic antidepressants, monoclonal anti-calcitonin gene-related peptide (anti-CGRP) antibodies, beta-blockers, antihypertensives, calcium channel inhibitors, other antidepressants (selective serotonin reuptake inhibitors, SSRIs, and dual-action antidepressants), other drugs, and polytherapy. Hormonal treatment and anti-inflammatories and triptans in minimum prophylaxis schemes (miniprophylaxis) will be covered in a specific chapter. The drug classes studied for part I of the Consensus were: anticonvulsants, tricyclic antidepressants, monoclonal anti-CGRP antibodies, and beta-blockers.

Pharmacokinetics and Pharmacological Properties of Chloroquine and Hydroxychloroquine in the Context of COVID-19 Infection

Chloroquine and hydroxychloroquine are quinoline derivatives used to treat malaria. To date, these medications are not approved for the treatment of viral infections, and there are no well‐controlled, prospective, randomized clinical studies or evidence to support their use in patients with coronavirus disease 2019 (COVID‐19). Nevertheless, chloroquine and hydroxychloroquine are being studied alone or in combination with other agents to assess their effectiveness in the treatment or prophylaxis for COVID‐19. The effective use of any medication involves an understanding of its pharmacokinetics, safety, and mechanism of action. This work provides basic clinical pharmacology information relevant for planning and initiating COVID‐19 clinical studies with chloroquine or hydroxychloroquine, summarizes safety data from healthy volunteer studies, and summarizes safety data from phase II and phase II/III clinical studies in patients with uncomplicated malaria, including a phase II/III study in pediatric patients following administration of azithromycin and chloroquine in combination. In addition, this work presents data describing the proposed mechanisms of action against the severe acute respiratory distress syndrome coronavirus–2 and summarizes clinical efficacy to date.

Efficacy and safety of erenumab (AMG334) in episodic migraine patients with prior preventive treatment failure: A subgroup analysis of a randomized, double-blind, placebo-controlled study

BACKGROUND

Erenumab was effective and well tolerated in a pivotal clinical trial of episodic migraine that included subjects both naïve to, and those who had failed, previous preventives. Here we evaluated the efficacy and safety of erenumab (70 mg or 140 mg) versus placebo in the subgroup of patients who had previously failed preventive treatment(s): ≥1 or ≥2 prior failed migraine preventive categories, and in patients who had never failed.

METHODS

Prespecified subgroup analyses evaluated change from baseline to months 4-6 (the primary endpoint of the blinded study phase) in monthly migraine days, achievement of ≥50% and ≥75% reduction in monthly migraine days, and change from baseline in acute migraine-specific medication days. Adverse events were also evaluated.

RESULTS

Treatment with both doses of erenumab resulted in greater reductions in monthly migraine days at months 4-6 (treatment difference versus placebo [95% CI], never failed subgroup: -0.9 [-1.5, -0.3] for 70 mg and -1.3 [-1.9, -0.7] for 140 mg; ≥1 prior failed medication categories subgroup: -2.0 [-2.8, -1.2] for 70 mg and -2.5 [-3.4, -1.7] for 140 mg; ≥2 prior failed medication categories subgroup: -1.3 [-2.6, 0.0] for 70 mg and -2.7 [-4.0, -1.4] for 140 mg). Similar results were observed in the monthly acute migraine-specific medication days endpoint, and in the achievement of ≥50% and ≥75% reduction in monthly migraine days. For the ≥50% reduction in monthly migraine day endpoint, placebo response in the no prior treatment failed group was 32.6%, in the ≥1 failed treatment 17.5%, and in the ≥2 failed treatments 11.1%.

CONCLUSION

Erenumab showed consistent efficacy in episodic migraine patients who had failed prior preventive treatments and was well tolerated across subgroups. The data suggest prior patients with prior treatment failures have lower placebo response rates.