Risk Summary
Available human data on the use of rizatriptan in pregnant women are not sufficient to draw conclusions about drug-associated risk for major birth defects and miscarriage.
In animal studies, developmental toxicity was observed following oral administration of rizatriptan during pregnancy (decreased fetal body weight in rats) or throughout pregnancy and lactation (increased mortality, decreased body weight, and neurobehavioral impairment in rat offspring) at maternal plasma exposures greater than that expected at therapeutic doses in humans [see
Animal Data].
In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. The reported rate of major birth defects among deliveries to women with migraine range from 2.2% to 2.9% and the reported rate of miscarriage was 17%, which are similar to rates reported in women without migraine.
Clinical Considerations
Disease-Associated Maternal and/or Embryo/Fetal Risk
In women with migraine, there is an increased risk of adverse perinatal outcomes in the mother, including pre-eclampsia and gestational hypertension.
Data
Human Data
The Pregnancy Registry for rizatriptan did not identify any pattern of congenital anomalies or other adverse birth outcomes over the period of 1998 to 2018. However, the lack of identification of any pattern should be viewed with caution, as the number of prospective reports with outcome information was low and did not provide sufficient power to detect an increased risk of individual birth defects associated with the use of rizatriptan. Additionally, there was significant loss to follow-up in the prospective pregnancy reports, further complicating this assessment of an association between rizatriptan and any pattern of congenital anomalies or other adverse birth outcomes.
In a study using data from the Swedish Medical Birth Register, live births to women who reported using triptans or ergots during pregnancy were compared with those of women who did not. Of the 157 births with first-trimester exposure to rizatriptan, 7 infants were born with malformations (relative risk 1.01 [95% CI: 0.40 to 2.08]). A study using linked data from the Medical Birth Registry of Norway to the Norwegian Prescription Database compared pregnancy outcomes in women who redeemed prescriptions for triptans during pregnancy, as well as a migraine disease comparison group who redeemed prescriptions for triptans before pregnancy only, compared with a population control group. Of the 310 women who redeemed prescriptions for rizatriptan during the first trimester, 10 had infants with major congenital malformations (OR 1.03 [95% CI: 0.55 to 1.93]), while for the 271 women who redeemed prescriptions for rizatriptan before but not during pregnancy, 12 had infants with major congenital malformations (OR 1.48 [95% CI: 0.83 to 2.64]), each compared with the population comparison group.
Animal Data
When rizatriptan (0, 2, 10, or 100 mg/kg/day) was administered orally to pregnant rats throughout organogenesis, a decrease in fetal body weight was observed at the highest doses tested. At the mid-dose (10 mg/kg/day), which was a no-effect dose for adverse effects on embryofetal development, plasma exposure (AUC) was approximately 15 times that in humans at the maximum recommended human dose (MRHD) of 30 mg/day. When rizatriptan (0, 5, 10, or 50 mg/kg/day) was administered orally to pregnant rabbits throughout organogenesis, no adverse fetal effects were observed. Plasma exposure (AUC) at the highest dose tested was 115 times that in humans at the MRHD. Placental transfer of the drug to the fetus was demonstrated in both species.
Oral administration of rizatriptan (0, 2, 10, or 100 mg/kg/day) to female rats before and during mating and continuing throughout gestation and lactation resulted in reduced body weight in offspring from birth and throughout lactation at all but the lowest dose tested (2 mg/kg/day). Plasma exposure (AUC) at the no-effect dose (2 mg/kg/day) for adverse effects on postnatal development was similar to that in humans at the MRHD.
Oral administration of rizatriptan (0, 5, 100, or 250 mg/kg/day) throughout organogenesis and lactation resulted in neonatal mortality, reduced body weight (which persisted into adulthood), and impaired neurobehavioral function in offspring at all but the lowest dose tested. Plasma exposure (AUC) at the no-effect dose for adverse effects on postnatal development (5 mg/kg/day) was approximately 8 times that in humans at the MRHD.
Data
Following oral administration of rizatriptan to lactating rats at a dose of 100 mg/kg/day, the drug concentrations of rizatriptan in milk samples exceeded maternal plasma drug concentrations by approximately 6-fold.
Absorption
Rizatriptan is completely absorbed following oral administration. The mean oral absolute bioavailability of the rizatriptan benzoate tablet is about 45% and mean peak plasma concentrations (C
max) are reached in approximately 1-1.5 hours (T
max). The presence of a migraine headache did not appear to affect the absorption or pharmacokinetics of rizatriptan. Food has no significant effect on the bioavailability of rizatriptan but delays the time to reach peak concentration by an hour. In clinical trials, rizatriptan benzoate tablets were administered without regard to food.
The bioavailability and C
max of rizatriptan were similar following administration of rizatriptan benzoate tablets and rizatriptan benzoate orally disintegrating tablets, but the rate of absorption is somewhat slower with the orally disintegrating tablets, with T
max delayed by up to 0.7 hour. AUC of rizatriptan is approximately 30% higher in females than in males. No accumulation occurred on multiple dosing.
Following a single dose of 10mg RizaFilm, the mean C
max and AUC
inf of rizatriptan were 23.79 (± 8.36) ng/mL and 84.54 (± 18.65) ng·hr/mL, respectively; the maximum peak plasma concentrations were achieved in 1.4 hours.
Distribution
The mean volume of distribution is approximately 140 liters in male subjects and 110 liters in female subjects. Rizatriptan is minimally bound (14%) to plasma proteins.
Metabolism
The primary route of rizatriptan metabolism is via oxidative deamination by monoamine oxidase-A (MAO-A) to the indole acetic acid metabolite, which is not active at the 5-HT1B/1D receptor. N-monodesmethyl-rizatriptan, a metabolite with activity similar to that of parent compound at the 5-HT
1B/1D receptor, is formed to a minor degree. Plasma concentrations of N-monodesmethyl-rizatriptan are approximately 14% of those of parent compound, and it is eliminated at a similar rate. Other minor metabolites, the N-oxide, the 6-hydroxy compound, and the sulfate conjugate of the 6-hydroxy metabolite are not active at the 5-HT
1B/1D receptor.
Elimination
The total radioactivity of the administered dose recovered over 120 hours in urine and feces was 82% and 12%, respectively, following a single 10-mg oral administration of
14C-rizatriptan. Following oral administration of
14C-rizatriptan, rizatriptan accounted for about 17% of circulating plasma radioactivity. Approximately 14% of an oral dose is excreted in urine as unchanged rizatriptan while 51% is excreted as indole acetic acid metabolite, indicating substantial first-pass metabolism.
Following administration of RizaFilm, the mean plasma half-life of rizatriptan is 2 hours.
Cytochrome P450 Isoforms
Rizatriptan is not an inhibitor of the activities of human liver cytochrome P450 isoforms 3A4/5, 1A2, 2C9, 2C19, or 2E1; rizatriptan is a competitive inhibitor (Ki =1400 nM) of cytochrome P450 2D6, but only at high, clinically irrelevant concentrations.
Specific Populations
Geriatric: Rizatriptan pharmacokinetics in healthy elderly non-migraineur volunteers (age 65-77 years) were similar to those in younger non-migraineur volunteers (age 18-45 years).
Pediatric: The pharmacokinetics of rizatriptan was determined in pediatric migraineurs 12 to 17 years of age. Exposures following single-dose administration of 10 mg rizatriptan benzoate orally disintegrating tablets to pediatric patients weighing ≥40 kg (88 lb) were similar to those observed following single-dose administration of 10 mg rizatriptan benzoate orally disintegrating tablets to adults.
Gender: The mean AUC
0-∞ and C
max of rizatriptan (10 mg orally) were about 30% and 11% higher in females as compared to males, respectively, while Tmax occurred at approximately the same time.
Patients with Hepatic Impairment: Following oral administration in patients with hepatic impairment caused by mild to moderate alcoholic cirrhosis of the liver, plasma concentrations of rizatriptan were similar in patients with mild hepatic insufficiency compared to a control group of subjects with normal hepatic function; plasma concentrations of rizatriptan were approximately 30% greater in patients with moderate hepatic insufficiency.
Patients with Renal Impairment: In patients with renal impairment (creatinine clearance 10-60 mL/min/1.73 m
2), the AUC
0-∞ of rizatriptan was not significantly different from that in subjects with normal renal function. In hemodialysis patients, (creatinine clearance <2 mL/min/1.73 m2), however, the AUC for rizatriptan was approximately 44% greater than that in patients with normal renal function.
Race: Pharmacokinetic data revealed no significant differences between African American and Caucasian subjects.
Carcinogenesis
Oral carcinogenicity studies were conducted in mice (100 weeks) and rats (106 weeks) at doses of up to 125 mg/kg/day. Plasma exposures (AUC) at the highest dose tested were approximately 150 (mice) and 240 times (rats) that in humans at the maximum recommended daily dose (MRDD) of 30 mg/day. There was no evidence of an increase in tumor incidence related to rizatriptan in either species.
Mutagenesis
Rizatriptan was neither mutagenic nor clastogenic in a battery of
in vitro and
in vivo genetic toxicity studies, including the microbial mutagenesis (Ames) assay,
in vitro mammalian cell mutagenesis and chromosomal aberration assays, and the
in vivo chromosomal aberration assay in mouse.
Impairment of Fertility
In a fertility study in rats, altered estrus cyclicity and delays in time to mating were observed in females treated orally with 100 mg/kg/day rizatriptan. The no-effect dose was 10 mg/kg/day (approximately 15 times the human exposure at the MRDD). There were no other fertility-related effects in the female rats. There was no impairment of fertility or reproductive performance in male rats treated with up to 250 mg/kg/day (approximately 550 times the human exposure at the MRDD).
Rizatriptan Benzoate Orally Disintegrating Tablets
The efficacy of rizatriptan benzoate orally disintegrating tablets was established in two multicenter, randomized, placebo-controlled trials that were similar in design to the trials of rizatriptan benzoate tablets (Studies 5 and 6). Patients were instructed to treat a moderate to severe headache. Patients treated in these studies were primarily female (88%) and Caucasian (95%), with a mean age of 42 years (range 18-72).
In both studies, the percentage of patients achieving headache response 2 hours after treatment was significantly greater in patients who received rizatriptan benzoate orally disintegrating tablets 10 mg compared to those who received placebo. The results from Studies 5 and 6 are summarized in Table 3.
Table 3: Response Rates 2 Hours Following Treatment of Initial Headache in Studies 5 and 6| Study | Placebo | Rizatriptan orally disintegrating tablets 10mg |
| 5 | 47% (n=98) | 66%*(n=113) |
| 6 | 28% (n=180) | 74%*(n=186) |
*p-value <0.01 in comparison with placebo |
The estimated probability of achieving an initial headache response by 2 hours following treatment with rizatriptan benzoate orally disintegrating tablets in pooled Studies 5 and 6 is depicted in Figure 3.
Figure 3: Estimated Probability of Achieving an Initial Headache Response with Rizatriptan Benzoate Orally Disintegrating Tablets by 2 Hours in pooled Studies 5 and 6** Figure 3 shows the Kaplan-Meier plot of the probability over time of obtaining headache response (no or mild pain) following treatment with rizatriptan benzoate orally disintegrating tablets or placebo. The averages displayed are based on pooled data from 2 placebo-controlled, outpatient trials providing evidence of efficacy (Studies 5 and 6). Patients taking additional treatment or not achieving headache response before 2 hours were censored at 2 hours. |
For patients with migraine-associated photophobia and phonophobia at baseline, there was a decreased incidence of these symptoms following administration of rizatriptan benzoate orally disintegrating tablets as compared to placebo.
Two to 24 hours following the initial dose of study treatment, patients were allowed to use additional treatment for pain response in the form of a second dose of study treatment or other medication. The estimated probability of patients taking a second dose or other medication for migraine over the 24 hours following the initial dose of study treatment is summarized in Figure 4.
Figure 4: Estimated Probability of Patients Taking a Second Dose of Rizatriptan Benzoate Orally Disintegrating Tablets or Other Medication for Migraines Over the 24 Hours Following the Initial Dose of Study Treatment in Pooled Studies 5 and 6** This Kaplan-Meier plot is based on data obtained in 2 placebo-controlled outpatient clinical trials (Studies 5 and 6). Patients not using additional treatments were censored at 24 hours. The plot includes both patients who had headache response at 2 hours and those who had no response to the initial dose. Remedication was not allowed within 2 hours post-dose. |
Administration Instructions
Advise patients to fold the pouch on the dotted line and tear open at the notch. Inform patients that administration with liquids is not necessary. Direct patients to place RizaFilm oral film on the tongue, where it will disintegrate and be swallowed with saliva [see
Dosage and Administration (2.3)].
Risk of Myocardial Ischemia and/or Infarction, Prinzmetal's Angina, Other Vasospasm-Related Events, and Cerebrovascular Events
Inform patients that RizaFilm may cause serious cardiovascular side effects such as myocardial infarction or stroke. Although serious cardiovascular events can occur without warning symptoms, patients should be alert for the signs and symptoms of chest pain, shortness of breath, weakness, slurring of speech, and should ask for medical advice when observing any indicative signs or symptoms. Patients should be apprised of the importance of this follow-up [see
Warnings and Precautions(5.1,
5.2,
5.4,
5.5) ].
Serotonin Syndrome
Patients should be cautioned about the risk of serotonin syndrome with the use of RizaFilm or other triptans, particularly during combined use with selective serotonin reuptake inhibitors (SSRIs) or serotonin norepinephrine reuptake inhibitors (SNRIs) [ see
Warnings and Precautions (5.7),
Drug Interactions (7.4), and
Clinical Pharmacology (12.3) ].
Pregnancy
Advise patients to notify their healthcare provider if they become pregnant during treatment or plan to become pregnant [ see
Use in Specific Populations (8.1) ].
Lactation
Advise patients to notify their healthcare provider if they are breastfeeding or plan to breastfeed [see
Use in Specific Populations (8.2)].
Ability To Perform Complex Tasks
Since migraines or treatment with RizaFilm may cause somnolence and dizziness, instruct patients to evaluate their ability to perform complex tasks during migraine attacks and after administration of RizaFilm.
Hypersensitivity Reactions
Inform patients that hypersensitivity reactions, including angioedema and anaphylaxis, have occurred in patients receiving rizatriptan. Inform patients that such reactions can be life threatening or fatal and to seek immediate medical attention if they have anaphylactic symptoms [see
Warnings and Precautions (5.6) ].
Medication Overuse Headache
Inform patients that use of acute migraine drugs for 10 or more days per month may lead to an exacerbation of headache and encourage patients to record headache frequency and drug use (e.g., by keeping a headache diary) [ see
Warnings and Precautions (5.7) ].
RizaFilm® is manufactured by:
IntelGenx Corp.
Saint-Laurent, Quebec H4S 1Y2 Canada
RizaFilm® is manufactured for:
Gensco Pharma
Doral, FL 33122
Revised: 12/2023
RizaFilm Oral Films are manufactured by:
IntelGenx Corp.
Saint-Laurent, Quebec, H4S 1Y2 Canada
RizaFilm Oral Films are manufactured for:
Gensco Pharma
Doral, FL, 33122
The brands listed are the trademarks of their respective owners.
This Patient Information has been approved by the U.S. Food and Drug Administration. Issued: 12/2023