A review of the 5-HT1B/1D agonist rizatriptan: update on recent research and implications for the future

Lasmiditan efficacy in migraine attacks with mild vs. moderate or severe pain

OBJECTIVE

To evaluate the efficacy of lasmiditan (LTN) in treating migraine attacks of mild vs. moderate or severe pain intensity.

METHODS

Pooled data from two single-attack, placebo-controlled studies (SAMURAI [NCT02439320] and SPARTAN [NCT02605174]), and a prospective, randomized, open-label study (GLADIATOR [NCT02565186]) were assessed. Efficacy measures included the proportion of attacks with 2-h pain freedom (PF), 2-h most bothersome symptom (MBS) freedom, and 24-h sustained pain freedom (SPF). Fisher's exact test was used to compare the proportion of PF, SPF, or MBS freedom outcomes among attacks treated at mild, moderate, or severe pain.

RESULTS

In SAMURAI and SPARTAN, most treated attacks were of moderate (N = 2768) or severe (N = 1147) intensity, compared to mild (N = 65). Numerically greater 2-h PF and 24-h SPF response rates were observed in attacks treated at mild compared to moderate or severe pain. Analysis of GLADIATOR data included 273 (1.5%), 11,644 (65.1%), and 5948 (33.3%) attacks treated when pain was mild, moderate, and severe, respectively. In general, a significantly greater proportion of attacks treated at mild pain achieved 2-h PF and MBS freedom, as well as 24-h SPF. The incidence of treatment-emergent adverse events in LTN treatment groups were similar regardless of baseline head pain intensity.

CONCLUSIONS

Data from two placebo-controlled, single-attack trials, and an open-label study including treatment of multiple attacks, suggested a tendency to relatively better efficacy outcomes when LTN treatment was initiated at mild vs. moderate to severe pain. Further research is needed to better understand the relationship of lasmiditan outcomes to the time of administration in the course of a migraine attack.

Bioequivalence Study of Two Orodispersible Rizatriptan Formulations of 10 mg in Healthy Volunteers

The aim of the study was to assess the bioequivalence and tolerability of two different oral formulations of rizatriptan. A bioequivalence study was carried out in 40 healthy volunteers according to an open label, randomized, two-period, two-sequence, crossover, single dose, and fasting conditions design. The test and reference formulations were administered in two treatment days, separated by a washout period of seven days. Plasma concentrations of rizatriptan were obtained by the LC/MS/MS (Liquid chromatography tandem-mass spectrometry) method. Log-transformed AUC0-t (area under the plasma concentration-time curve from zero to the last measurable concentration) and Cmax (maximum plasma concentration) values were tested for bioequivalence based on the ratios of the geometric means (test/reference). The tmax (time to reach maximum plasma concentration) was analysed nonparametrically. The 90% confidence intervals of the geometric mean values for the test/reference ratios for AUC0-t and Cmax were within the bioequivalence acceptance range of 80%-125%. According to the European Guideline, it may therefore be concluded that the test formulation of rizatriptan 10 mg orodispersible tablet is bioequivalent to the reference formulation (Maxalt® Max 10 mg oral lyophilisate). The safety profile of both formulations was consistent with the summary of the product characteristics.

Efficacy and pharmacokinetic activity of frovatriptan compared to rizatriptan in patients with moderate-to-severe migraine

BACKGROUND

Migraine is a painful neurological disorder that affects over 10% of the general population. Frovatriptan and rizatriptan are antimigraine agents belonging to the triptan class. Although previous studies have independently compared the efficacy of these agents, contemporaneous data examining both pharmacokinetic (PK) properties and efficacy in parallel have not previously been available.

MATERIALS AND METHODS

In this single-center double-blind study, 18 subjects (ten female) were treated for a single migraine attack with frovatriptan 2.5 mg or rizatriptan 10 mg. Plasma concentrations were measured predose and at 2, 4, 6, 12, 24, 48, and 72 hours after drug administration. The primary end point of this study was to evaluate the association between PK parameters and efficacy measures and recurrence rate. Secondary end points were pain-free and pain-relief episodes at 2 and 4 hours, recurrent episodes within 48 hours, and cumulative hazard of recurrence within 72 hours.

RESULTS

At baseline, approximately 17% of patients had mild migraine, while 83% had moderate-severe migraine. Although the time to maximum concentration was similar for both drugs (2.7 versus 2.3 hours), the terminal half-life for frovatriptan was longer than rizatriptan (29.3 versus 3.2 hours, P<0.0001). The proportion of patients who were pain-free at 4 hours without rescue medication was higher in the frovatriptan-treated group, (38.9 versus 5.6%, P=0.045). The cumulative hazard of recurrence over 72 h was reduced by frovatriptan compared to rizatriptan-treated patients (log-rank test, P=0.04). Pain-free and pain-relief episodes for the study period were positively correlated with the concentration:maximum concentration (Cmax) ratio for frovatriptan (r=0.52, P=0.028), but not rizatriptan. Recurrence rate was negatively correlated with the concentration:Cmax ratio for both frovatriptan (r=-0.96, P=0.0024) and rizatriptan (r=-0.98, P=0.0004). Fewer adverse events were observed for frovatriptan compared to rizatriptan (one versus eight, P=0.021).

CONCLUSION

This pilot study indicates that a similar extent of initial pain relief is afforded by both triptans in migraine treatment. The longer duration of action of frovatriptan parallels and correlates with its PK profile.

Combined analgesics in (headache) pain therapy: shotgun approach or precise multi-target therapeutics?

BACKGROUND

Pain in general and headache in particular are characterized by a change in activity in brain areas involved in pain processing. The therapeutic challenge is to identify drugs with molecular targets that restore the healthy state, resulting in meaningful pain relief or even freedom from pain. Different aspects of pain perception, i.e. sensory and affective components, also explain why there is not just one single target structure for therapeutic approaches to pain. A network of brain areas ("pain matrix") are involved in pain perception and pain control. This diversification of the pain system explains why a wide range of molecularly different substances can be used in the treatment of different pain states and why in recent years more and more studies have described a superior efficacy of a precise multi-target combination therapy compared to therapy with monotherapeutics.

DISCUSSION

In this article, we discuss the available literature on the effects of several fixed-dose combinations in the treatment of headaches and discuss the evidence in support of the role of combination therapy in the pharmacotherapy of pain, particularly of headaches. The scientific rationale behind multi-target combinations is the therapeutic benefit that could not be achieved by the individual constituents and that the single substances of the combinations act together additively or even multiplicatively and cooperate to achieve a completeness of the desired therapeutic effect.As an example the fixed-dose combination of acetylsalicylic acid (ASA), paracetamol (acetaminophen) and caffeine is reviewed in detail. The major advantage of using such a fixed combination is that the active ingredients act on different but distinct molecular targets and thus are able to act on more signalling cascades involved in pain than most single analgesics without adding more side effects to the therapy.

SUMMARY

Multitarget therapeutics like combined analgesics broaden the array of therapeutic options, enable the completeness of the therapeutic effect, and allow doctors (and, in self-medication with OTC medications, the patients themselves) to customize treatment to the patient's specific needs. There is substantial clinical evidence that such a multi-component therapy is more effective than mono-component therapies.

A double-blind, randomized, multicenter, Italian study of frovatriptan versus rizatriptan for the acute treatment of migraine

The objective of this study was to assess patient satisfaction with acute treatment of migraine with frovatriptan or rizatriptan by preference questionnaire. 148 subjects with a history of migraine with or without aura (IHS 2004 criteria), with at least one migraine attack per month in the preceding 6 months, were enrolled and randomized to frovatriptan 2.5 mg or rizatriptan 10 mg treating 1-3 attacks. The study had a multicenter, randomized, double-blind, cross-over design, with treatment periods lasting <3 months. At the end of the study, patients assigned preference to one of the treatments using a questionnaire with a score from 0 to 5 (primary endpoint). Secondary endpoints were pain-free and pain relief episodes at 2 h, and recurrent and sustained pain-free episodes within 48 h. 104 of the 125 patients (83%, intention-to-treat population) expressed a preference for a triptan. The average preference score was not significantly different between frovatriptan (2.9±1.3) and rizatriptan (3.2±1.1). The rates of pain-free (33% frovatriptan vs. 39% rizatriptan) and pain relief (55 vs. 62%) episodes at 2 h were not significantly different between the two treatments. The rate of recurrent episodes was significantly (p<0.001) lower under frovatriptan (21 vs. 43% rizatriptan). No significant differences were observed in sustained pain-free episodes (26% frovatriptan vs. 22% rizatriptan). The number of patients with adverse events was not significantly different between rizatriptan (34) and frovatriptan (25, p=NS). The results suggest that frovatriptan has a similar efficacy to rizatriptan, but a more prolonged duration of action.

Ten years of rizatriptan: from development to clinical science and future directions

The year 2008 marked the 10th anniversary since rizatriptan was first launched for the acute treatment of migraine. In this article we discuss the concepts that motivated the preclinical and clinical development of rizatriptan, the clinical evidence that has driven its use over the past decade, rizatriptan's overall contribution to the field, and future directions for research.

Migraine strikes study: factors in patients' decision to treat early

To describe factors associated with early treatment of migraine, and to examine reasons patients do not treat early, this cross-sectional observational study email-recruited migraineurs ≥18-years-old who were currently prescribed acute migraine medication. Within 24 h of migraine resolution, eligible patients completed an online migraine strikes questionnaire which addressed pain severity, associated symptoms, and other variables including reasons for not treating early. Results reported were descriptive. Among 1,044 evaluable patients, early treatment was significantly associated with several factors such as leisure activity at onset (OR 1.32, P = 0.010), photophobia (OR 1.39, P = 0.013), diagnosis of migraine with aura (OR 1.36, P = 0.004), and other factors. Among 840 patients who reported wanting to treat earlier desire to reserve medication for a severe migraine was the most common reason given for not doing so (51.2%). Overcoming these factors may facilitate earlier migraine treatment.