Migraine Treatment and Healthcare Resource Utilization in Alberta, Canada.

BACKGROUND: Migraine poses a significant burden worldwide; however, there is limited evidence as to the burden in Canada. This study examined the treatment patterns, healthcare resource use (HRU), and costs among newly diagnosed or recurrent patients with migraine in Alberta, Canada, from the time of diagnosis or recurrence. METHODS: This retrospective observational study utilized administrative health data from Alberta, Canada. Patients were included in the Total Migraine Cohort if they had: (1) ≥1 International Classification of Diseases diagnostic code for migraine; or (2) ≥1 prescription dispense(s) for triptans from April 1, 2012, to March 31, 2018, with no previous diagnosis or dispensation code from April 1, 2010, to April 1, 2012. RESULTS: The mean age of the cohort (n = 199,931) was 40.0 years and 72.3% were women. The most common comorbidity was depression (19.7%). In each medication class examined, less than one-third of the cohort was prescribed triptans and fewer than one-fifth was prescribed a preventive. Among patients with ≥1 dispense, the mean rate of opioid prescriptions was 4.61 per patient-year, compared to 2.28 triptan prescriptions per patient-year. Migraine-related HRU accounted for 3%-10% of all use. CONCLUSION: Comorbidities and high all-cause HRU were observed among newly diagnosed or recurrent patients with migraine. There is an underutilization of acute and preventive medications in the management of migraine. The high rate of opioid use reinforces the suboptimal management of migraine in Alberta. Migraine management may improve by educating healthcare professionals to optimize treatment strategies.

Burden of Episodic Migraine, Chronic Migraine, and Medication Overuse Headache in Alberta.

OBJECTIVE: To describe demographic and clinical characteristics, healthcare resource use, costs, and treatment patterns in three migraine cohorts. METHODS: This retrospective observational study using administrative data examined patients with episodic migraine (EM), chronic migraine (CM) (without medication overuse headache [MOH]), and medication overuse headache in Alberta, Canada. Migraine patients were identified between 2012 and 2018 based on ≥ 1 diagnostic codes or triptan prescription. Patients with CM were defined using parameter estimates of a logistic regression model, and MOH was defined as patients with an average of ≥ 15 supply days covered of acute medications. EM was defined as patients without CM or MOH. Study outcomes were summarized using descriptive statistics. RESULTS: Patients with EM (n = 144,574), CM (n = 27,283), and MOH (n = 11,485) were included. Higher rates of healthcare use and costs were observed for CM (mean [SD] all-cause cost: ($12,693 [40,664]) and MOH ($16,611.5 [$38,748]) versus episodic migraine ($4,251 [$40,637]). Across all cohorts, opioids were the most dispensed acute medication (range across cohorts: 31.7%-89.8%), while antidepressants and anticonvulsants were the most dispensed preventive medication. Preventative medication classes were used by a minority of patients in each cohort, except anticonvulsants, where 50% of medication overuse patients had a dispensation. CONCLUSIONS: Patients with CM and MOH have a greater burden of illness compared to patients with EM. The overutilization of acute medication, particularly opioids, and the underutilization of preventive medications highlight an unmet need to more effectively manage migraine.

Phase I dose-finding study of weekly single-agent patupilone in patients with advanced solid tumors.

PURPOSE: To evaluate the safety and maximum-tolerated dose (MTD) of weekly patupilone, a natural epothilone B, in patients with advanced solid tumors. PATIENTS AND METHODS: Patients were treated with patupilone (0.3 to 3.6 mg/m2) for 6 weeks on/3 weeks off or 3 weeks on/1 week off. Dose-limiting toxicities (DLTs), MTD, and pharmacokinetics were determined for each schedule of administration. RESULTS: Ninety-one patients were enrolled. The most common tumor types included ovarian, breast, and colon cancers. Doses of patupilone less than 2.5 mg/m2 using either the 6 weeks on/3 weeks off or the 3 weeks on/1 week off schedule were tolerated well. At higher doses, DLTs were observed using both dosing schedules, with diarrhea the most common DLT. The MTD for both treatment schedules was 2.5 mg/m2. After a short infusion, patupilone blood concentrations declined in a multiphasic manner with a terminal half-life of 4 days. Drug clearance was nonrenal and was not related to body-surface area. Over the dose range evaluated, systemic drug exposure was approximately dose proportional. Three patients achieved a partial response, and 31 patients had stable disease. Two patients experiencing a partial response had received prior taxane therapy. CONCLUSION: Patupilone is well tolerated when administered at a dose of 2.5 mg/m2, using either a 6 weeks on/3 weeks off or a 3 weeks on/1 week off schedule. In contrast with murine studies, patupilone has a relatively prolonged terminal half-life in humans. The partial responses in patients previously treated with taxanes is consistent with promising preclinical results.

STI571 enhances the therapeutic index of epothilone B by a tumor-selective increase of drug uptake.

PURPOSE: The purpose is to investigate whether STI571, through platelet-derived growth factor receptor inhibition, enhances the therapeutic response to the chemotherapeutic drug epothilone B (EPO906) and, if so, to analyze the mechanism(s) underlying the effect. EXPERIMENTAL DESIGN: SCID mice with s.c. human anaplastic thyroid carcinomas were treated with different doses of EPO906 alone or in combination with STI571 and with different timing of STI571 and EPO906 administration. Tumor growth, tumor interstitial fluid pressure (IFP), and uptake of EPO906 in tumors and normal organs were monitored. RESULTS: STI571 potentiated the therapeutic effect of EPO906. Tumors subjected to combination treatment were >40% smaller than those subjected to monotreatment with EPO906. The improved efficacy was matched by reduced tumor IFP and a 3-fold increase in the tumor levels of EPO906. No significant increase of EPO906 levels was seen in liver, kidney, or the intestinal tract. Cotreatment did not reduce the tolerability of EPO906, as determined by measuring body weight throughout treatment. STI571-induced reduction in tumor IFP and increase in tumor uptake required a minimum of three daily doses of STI571 and was not observed 3 days after last treatment with STI571. The enhancement of EPO906 therapeutic efficacy was only observed when STI571 was scheduled in a manner associated with reduced tumor IFP and increased tumor uptake of EPO906. CONCLUSIONS: We conclude that STI571 increases the therapeutic index of EPO906 by selectively increasing the EPO906 uptake in tumors. The correlations between STI571 effects on tumor IFP and tumor drug uptake of EPO906 suggest a causal relationship between these phenomena. The study thus validates STI571 for combination treatment to enhance the therapeutic index of EPO906 in particular and, possibly, of chemotherapeutics in general.

Pharmacokinetic and pharmacodynamic assessments of HMG-CoA reductase inhibitors when coadministered with everolimus.

The authors assessed the mutual influence of the immunosuppressant everolimus (Certican) and the HMG-CoA reductase inhibitors atorvastatin and pravastatin when coadministered based on pharmacokinetic and pharmacodynamic measures. In this randomized, open-label, three-way crossover study, 24 healthy men received three single-dose oral treatments: 2 mg everolimus, 20 mg atorvastatin (n = 12) or 20 mg pravastatin (n = 12), and the respective statin coadministered with everolimus. Consecutive treatments were separated by a 14-day washout. The pharmacokinetics of all three drugs and total HMG-CoA reductase inhibitors were measured. Everolimus Cmax was reduced by 9% and 10% with atorvastatin and pravastatin coadministration; the corresponding decreases in everolimus AUC were 5% and 6%, respectively. Everolimus coadministration increased the Cmax of atorvastatin by 11% but had no influence on atorvastatin AUC. Coadministration of everolimus with pravastatin was associated with a 10% decrease in pravastatin Cmax and a 5% decrease in the AUC. The elimination half-lives of the two statins were unaffected by everolimus. Changes in total HMG-CoA reductase inhibitors in plasma exhibited generally similar patterns as for the parent statin exposures. Single-dose administrations of everolimus with either atorvastatin or pravastatin did not influence the pharmacokinetics of everolimus, atorvastatin, pravastatin, or total HMG-CoA reductase inhibitors in plasma to a clinically relevant extent.

Tegaserod pharmacokinetics are similar in patients with severe renal insufficiency and in healthy subjects.

Tegaserod (HTF 919), a selective 5-HT4 receptor partial agonist with promotile activity throughout the gastrointestinal tract, is in development for the treatment of irritable bowel syndrome. In an open-label, parallel-group study, the pharmacokinetics of a single 12-mg oral dose of tegaserod in patients with severe renal insufficiency requiring hemodialysis were compared with data obtained from healthy subjects matched for age, weight, height, and gender (n = 10, both). The pharmacokinetics of tegaserod were similar in both groups (AUC(0h-tz), ng.h/ml: 14.6 +/- 8.5 vs. 14.3 +/- 7.1; Cmax, ng/ml: 4.6 +/- 2.3 vs. 5.1 +/- 2.2; tmax, h: 1.0, for both). Tegaserod had similar tolerability in renally impaired patients and healthy volunteers, with adverse events largely related to the gastrointestinal pharmacological actions of the drug. Therefore, no dose adjustment of tegaserod is necessary for patients with renal insufficiency.

Effect of rifampicin on the pharmacokinetics of imatinib mesylate (Gleevec, STI571) in healthy subjects.

OBJECTIVE: This study was carried out to investigate the influence of CYP3A induction with rifampicin on imatinib (Gleevec) exposure. METHODS: The study employed a single center, single-sequence design. A group of 14 healthy male and female subjects received imatinib as a single 400 mg oral dose on two occasions: on study day 1 and on study day 15. Rifampicin treatment (600 mg once daily) for CYP4503A induction was initiated on study day 8 and maintained until day 18. Imatinib pharmacokinetics were determined up to 96 h after dosing on day 1 (no induction) and on days 15-18 (during concomitant rifampicin). Plasma concentrations of imatinib and its main metabolite CGP74588 were determined using a LC/MS/MS method. The ratio of 6beta-hydroxycortisol to cortisol excreted in the urine was measured to monitor the induction of CYP3A. RESULTS: During concomitant rifampicin administration, the mean imatinib C(max), AUC(0-24) and AUC(0- infinity ) decreased by 54% (90% CI: 48-60%), 68% (64-70%) and 74% (71-76%), respectively. The increase in clearance (Cl/f) was 385% (348-426%) during rifampicin treatment. The mean C(max) and AUC(0-24) of the metabolite CGP74588 increased by 88.6% (68.3%-111.4%) and 23.9% (13.5%-35.2%) after rifampicin pretreatment. However, the AUC(0- infinity ) decreased by 11.7% (3.3-19.4%). All subjects demonstrated a marked induction of hepatic microsomal CYP3A analyzed by the excretion ratio of 6beta-hydroxycortisol to cortisol from a mean baseline concentration of 5.6 U to 50.5 U. CONCLUSION: Concomitant use of imatinib and rifampicin or other potent inducers of CYP4503A may result in subtherapeutic plasma concentrations of imatinib. In patients in whom rifampicin or other CYP3A inducers are prescribed, alternative therapeutic agents with less potential for enzyme induction should be selected.

Bioequivalence, safety, and tolerability of imatinib tablets compared with capsules.

PURPOSE: Imatinib (Glivec) has been established as a highly effective therapy for chronic myeloid leukemia and gastrointestinal tumors. The recommended daily dosage of 400-600 mg requires simultaneous intake of up to six of the current 100-mg capsules. Due to the need to swallow multiple capsules per dose, there is a potential negative impact on treatment adherence; therefore, a new imatinib 400-mg film-coated tablet has been developed. To improve dosing flexibility, particularly with regard to the pediatric population and the management of adverse events, a scored 100-mg film-coated tablet has also been introduced. EXPERIMENTAL DESIGN: A group of 33 healthy subjects were randomly assigned to one of six treatment sequences, in which they received imatinib as 4 x 100-mg capsules (reference), 4 x 100-mg scored tablets (test), and 1 x 400-mg tablet (test). Blood sampling was performed for up to 96 h after dosing, followed by a 10-day washout period prior to the next sequence. After the third dosing, subjects were monitored to assess delayed drug-related adverse events. Pharmacokinetic parameters were assessed using concentration-time curves for plasma imatinib and its metabolite CGP74588. RESULTS: Median Tmax was 2.5 h for capsules and tablets. Mean AUC((0-inf)) values were 27,094, 26,081 and 25,464 ng.h/ml for 4 x 100-mg capsules, 4 x 100-mg tablets, and 1 x 400-mg tablets, respectively. Cmax values were 1748, 1638 and 1606 ng/ml, and t(1/2) values were 15.8, 15.9 and 15.7 h. The test/reference ratios for AUC((0-inf)), AUC((0-96) (h)), and C(max) were 0.98, 0.98 and 0.95 for 4 x 100-mg tablets versus 4 x 100-mg capsules, and 0.95, 0.95 and 0.92 for 1 x 400-mg tablet versus 4 x 100-mg capsules. The 95% confidence intervals were fully contained within the interval (0.80, 1.25). Eight mild and one moderate adverse event considered to be drug related were reported. These events showed no clustering by type of dosage form and were of little to no clinical significance. CONCLUSIONS: Film-coated 100-mg (scored) and 400-mg tablet dose forms of imatinib are bioequivalent to the commercial 100-mg hard-gelatin capsule, and are as safe and well tolerated.

Steady-state pharmacokinetics of fluvastatin in healthy subjects following a new extended release fluvastatin tablet, Lescol XL.

This was an open-label, randomized, three-period, three-treatment, multiple dose, crossover study in 12 healthy male and female subjects. This study evaluated single dose and steady-state pharmacokinetics of fluvastatin following single and multiple dose administrations of a new extended release fluvastatin 8 h matrix tablet, Lescol XL 80 mg and 160 mg doses once a day. The study also included a twice a day administration of an immediate release (IR) form of fluvastatin capsule, Lescol, for comparative purposes. All doses were administered for 7 days. The safety and tolerability were also assessed. The pharmacokinetics of fluvastatin were evaluated on days 1 and 7 following each treatment. Fluvastatin systemic exposure was 50% less when administered as Lescol XL 80 mg qd compared with Lescol IR 40 mg bid. Conversely, fluvastatin systemic exposure was 22% higher when administered as Lescol XL 160 mg qd compared with Lescol IR 40 mg bid. Single doses of Lescol XL 80 mg and 160 mg were dose proportional but, deviation (30%) from dose proportionality was observed for the Lescol XL 160 mg at steady-state. There appeared to be moderate (20%-40%) accumulation of serum fluvastatin maximal concentrations and exposure after multiple doses of Lescol XL tablets. Both Lescol XL 80 mg and 160 mg showed delayed absorption and longer apparent elimination half-life compared with fluvastatin IR capsule. Single and multiple doses of fluvastatin were generally well tolerated in this healthy volunteer population. Adverse event profiles were consistent with the published safety profile of the marketed formulations. Aside from one incidence of creatine phosphokinase (CPK) elevation (following Lescol XL 160 mg qd treatment), there were no safety concerns with any of the treatments when administered acutely (7 days).