Absorption and Bioavailability: Sumavel DosePro is bioequivalent to sumatriptan needle-based injection via autoinjector at the thigh and abdomen administration sites. A sub-optimal dose may be delivered when administered to the arm and therefore, the arm is not recommended as a site of administration.
Pharmacokinetic parameters following a 6 mg subcutaneous dose of Sumavel DosePro into the thigh were determined in 32 subjects (males and females). The maximum serum concentration (Cmax) (mean ± standard deviation) was 71.9 ± 14.4 ng/mL; the time to peak concentration (Tmax) was 12 minutes after dosing (range, 4 to 20 minutes); and the terminal half-life was 103 ± 22 minutes.
Pharmacokinetic parameters following a 6 mg subcutaneous dose of Sumavel DosePro into the abdomen were determined in 35 subjects (males and females). The maximum serum concentration (Cmax) (mean ± standard deviation) was 78.6 ± 17.3 ng/mL; the time to peak concentration (Tmax) was 12 minutes after dosing (range, 6 to 20 minutes); and the terminal half-life was 102 ± 12 minutes.
Distribution: The bioavailability of sumatriptan via subcutaneous site injection to 18 healthy male subjects was 97% ± 16% of that obtained following intravenous injection. Protein binding, determined by equilibrium dialysis over the concentration range of 10 to 1,000 ng/mL, is low, approximately 14% to 21%. The effect of sumatriptan on the protein binding of other drugs has not been evaluated.
Metabolism: In vitro studies with human microsomes suggest that sumatriptan is metabolized by MAO, predominantly the A isoenzyme. Most of a radiolabeled dose of sumatriptan excreted in the urine is the major metabolite indole acetic acid (IAA) or the IAA glucuronide, both of which are inactive.
Elimination: After a single 6 mg subcutaneous dose, 22% ± 4% was excreted in the urine as unchanged sumatriptan and 38% ± 7% as the IAA metabolite.
Special Populations: Age: The pharmacokinetics of sumatriptan in the elderly (mean age: 72 years, 2 males and 4 females) and in subjects with migraine (mean age: 38 years, 25 males and 155 females) were similar to that in healthy male subjects (mean age: 30 years).
Renal Impairment: The effect of renal impairment on the pharmacokinetics of sumatriptan has not been examined.
Hepatic Impairment: The effect of mild to moderate hepatic disease on the pharmacokinetics of subcutaneously administered sumatriptan has been evaluated. There were no significant differences in the pharmacokinetics of subcutaneously administered sumatriptan in moderately hepatically impaired subjects compared with healthy controls. The pharmacokinetics of subcutaneously administered sumatriptan in patients with severe hepatic impairment has not been studied. The use of Sumavel DosePro in this population is not recommended [see Use in Specific Populations (8.6)].
Race: The systemic clearance and Cmax of sumatriptan were similar in Black (n = 34) and Caucasian (n = 38) healthy male subjects.
Drug Interaction Studies: Monoamine Oxidase-A Inhibitors: In a trial of 14 healthy females, pretreatment with an MAO-A inhibitor decreased the clearance of sumatriptan, resulting in a 2-fold increase in the area under the sumatriptan plasma concentration-time curve (AUC), corresponding to a 40% increase in elimination half-life.