Belsomra

Overdose

There is limited premarketing clinical experience with an overdosage of BELSOMRA. In clinical pharmacology studies, healthy subjects who were administered morning doses of up to 240 mg of suvorexant showed dose-dependent increases in the frequency and duration of somnolence.

General symptomatic and supportive measures should be used, along with immediate gastric lavage where appropriate. Intravenous fluids should be administered as needed. As in all cases of drug overdose, vital signs should be monitored and general supportive measures employed. The value of dialysis in the treatment of overdosage has not been determined. As suvorexant is highly protein-bound, hemodialysis is not expected to contribute to elimination of suvorexant.

As with the management of all overdosage, the possibility of multiple drug ingestion should be considered. Consider contacting a poison control center for up-to-date information on the management of hypnotic drug product overdosage.

Contraindications

BELSOMRA is contraindicated in patients with narcolepsy.

Undesirable effects

The following serious adverse reactions are discussed in greater detail in other sections:

• CNS depressant effects and daytime impairment
• Abnormal thinking and behavioral changes
• Worsening of Depression/Suicidal ideation
• Sleep paralysis, hypnagogic/hypnopompic hallucinations, cataplexy-like symptoms

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

In 3-month controlled efficacy trials (Study 1 and Study 2), 1263 patients were exposed to BELSOMRA including 493 patients who received BELSOMRA 15 mg or 20 mg (see Table 1).

In a long-term study, additional patients (n=521) were treated with BELSOMRA at higher than recommended doses, including a total of 160 patients who received BELSOMRA for at least one year.

Table 1: Patient Exposure to BELSOMRA 15 mg or 20 mg in Study 1 and Study 2

The pooled safety data described below (see Table 2) reflect the adverse reaction profile during the first 3 months of treatment.

The incidence of discontinuation due to adverse reactions for patients treated with 15 mg or 20 mg of BELSOMRA was 3% compared to 5% for placebo. No individual adverse reaction led to discontinuation at an incidence ≥ 1%.

In clinical trials of patients with insomnia treated with BELSOMRA 15 mg or 20 mg, the most common adverse reaction (reported in 5% or more of patients treated with BELSOMRA and at least twice the placebo rate) was somnolence (BELSOMRA 7%; placebo 3%).

Table 2 shows the percentage of patients with adverse reactions during the first three months of treatment, based on the pooled data from 3-month controlled efficacy trials (Study 1 and Study 2).

At doses of 15 or 20 mg, the incidence of somnolence was higher in females (8%) than in males (3%). Of the adverse reactions reported in Table 2, the following occurred in women at an incidence of at least twice that in men: headache, abnormal dreams, dry mouth, cough, and upper respiratory tract infection.

The adverse reaction profile in elderly patients was generally consistent with non-elderly patients. The adverse reactions reported during long-term treatment up to 1 year were generally consistent with those observed during the first 3 months of treatment.

Table 2: Percentage of Patients with Adverse Reactions Incidence ≥ 2% and Greater than Placebo in 3-Month Controlled Efficacy Trials (Study 1 and Study 2)

There is evidence of a dose relationship for many of the adverse reactions associated with BELSOMRA use, particularly for certain CNS adverse reactions.

In a placebo-controlled crossover study (Study 3), non-elderly adult patients were treated for up to one month with BELSOMRA at doses of 10 mg, 20 mg, 40 mg (2 times the maximum recommended dose) or 80 mg (4 times the maximum recommended dose). In patients treated with BELSOMRA 10 mg (n=62), although no adverse reactions were reported at an incidence of ≥ 2%, the types of adverse reactions observed were similar to those observed in patients treated with BELSOMRA 20 mg. BELSOMRA was associated with a dose-related increase in somnolence: 2% at the 10 mg dose, 5% at the 20 mg dose, 12% at the 40 mg dose, and 11% at the 80 mg dose, compared to < 1% for placebo. BELSOMRA was also associated with a dose-related increase in serum cholesterol: 1 mg/dL at the 10 mg dose, 2 mg/Dl at the 20 mg dose, 3 mg/dL at the 40 mg dose, and 6 mg/dL at the 80 mg dose after 4 weeks of treatment, compared to a 4 mg/dL decrease for placebo.

Therapeutic indications

BELSOMRA® (suvorexant) is indicated for the treatment of insomnia characterized by difficulties with sleep onset and/or sleep maintenance.

Pharmacodynamic properties

The effects of suvorexant on the QTc interval were evaluated in a randomized, placebo-, and activecontrolled (moxifloxacin 400 mg) crossover study in healthy subjects (n=53). The upper bound of the one-sided 95% confidence interval for the largest placebo-adjusted, baseline-corrected QTc interval was below 10 ms based on analysis of suvorexant doses up to 240 mg, 12 times the maximum recommended dose. BELSOMRA thus does not prolong the QTc interval to any clinically relevant extent.

Pharmacokinetic properties

Suvorexant exposure increases in a less than strictly dose-proportional manner over the range of 10-80 mg because of decreased absorption at higher doses. Suvorexant pharmacokinetics are similar in healthy subjects and patients with insomnia.

Suvorexant peak concentrations occur at a median Tmax of 2 hours (range 30 minutes to 6 hours) under fasted conditions. The mean absolute bioavailability of 10 mg is 82%.

Ingestion of suvorexant with a high-fat meal resulted in no meaningful change in AUC or Cmax but a delay in Tmax of approximately 1.5 hours. Suvorexant may be taken with or without food; however for faster sleep onset, suvorexant should not be administered with or soon after a meal.

The mean volume of distribution of suvorexant is approximately 49 liters. Suvorexant is extensively bound ( > 99%) to human plasma proteins and does not preferentially distribute into red blood cells. Suvorexant binds to both human serum albumin and α1-acid glycoprotein.

Suvorexant is mainly eliminated by metabolism, primarily by CYP3A with a minor contribution from CYP2C19. The major circulating entities are suvorexant and a hydroxy-suvorexant metabolite. This metabolite is not expected to be pharmacologically active.

The primary route of elimination is through the feces, with approximately 66% of radiolabeled dose recovered in the feces compared to 23% in the urine. The systemic pharmacokinetics of suvorexant are linear with an accumulation of approximately 1- to 2-fold with once-daily dosing. Steady-state is achieved by 3 days. The mean t½ is approximately 12 hours (95% CI: 12 to 13).

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Fertility, pregnancy and lactation

There are no adequate and well-controlled studies in pregnant women. BELSOMRA should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Administration of suvorexant to pregnant rats throughout organogenesis in two separate studies at oral doses of 30, 150, and 1000 mg/kg or 30, 80, and 325 mg/kg resulted in a decrease in fetal body weight at doses greater than 80 mg/kg. Plasma exposures (AUC) at the no-effect dose were approximately 25 times that in humans at the maximum recommended human dose (MRHD) of 20 mg/day.

Administration of suvorexant to pregnant rabbits throughout organogenesis in two separate studies at oral doses of 40, 100, and 300 mg/kg or 50, 150, and 325 mg/kg resulted in no apparent adverse effects on embryo-fetal development. Excessive toxicity resulted in premature sacrifice of pregnant animals at 325 mg/kg. The highest maternal plasma exposures (AUC) for which there are fetal data were up to approximately 40 times that in humans at the MRHD.

Administration of suvorexant (oral doses of 30, 80, and 200 mg/kg) to pregnant rats throughout gestation and lactation resulted in decreased body weight in offspring at the highest dose tested. Plasma AUCs at the no-effect dose were approximately 25 times that in humans at the MRHD.

Qualitative and quantitative composition

• 5 mg tablets are yellow, round, film-coated tablets with “5” on one side and plain on the other side.
• 10 mg tablets are green, round, film-coated tablets with “33” on one side and plain on the other side.
• 15 mg tablets are white, oval, film-coated tablets with the Merck logo on one side and “325” on the other side.
• 20 mg tablets are white, round, film-coated tablets with the Merck logo and “335” on one side and plain on the other side.

No. 3062 — BELSOMRA tablets, 5 mg, are yellow, round, film-coated tablets, with “5” on one side and plain on the other side. They are supplied as follows: NDC 0006-0005-30 unit-of-use blisters of 30

No. 3063 — BELSOMRA tablets, 10 mg, are green, round, film-coated tablets, with “33” on one side and plain on the other side. They are supplied as follows: NDC 0006-0033-30 unit-of-use blisters of 30

No. 3981 — BELSOMRA tablets, 15 mg, are white, oval, film-coated tablets with the Merck logo on one side and “325” on the other side. They are supplied as follows: NDC 0006-0325-30 unit-of-use blisters of 30

No. 3982 — BELSOMRA tablets, 20 mg, are white, round, film-coated tablets with the Merck logo and “335” on one side and plain on the other side. They are supplied as follows: NDC 0006-0335-30 unitof- use blisters of 30

Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F),. Store in the original package until use to protect from light and moisture.

Merck Sharp & Dohme Corp., a subsidiary of MERCK & CO., INC., Whitehouse Station, NJ 08889, USA. Revised: May 2016.

Special warnings and precautions for use

Included as part of the PRECAUTIONS section.

BELSOMRA is a central nervous system (CNS) depressant that can impair daytime wakefulness even when used as prescribed. Prescribers should monitor for somnolence and CNS depressant effects, but impairment can occur in the absence of symptoms, and may not be reliably detected by ordinary clinical exam (i.e., less than formal testing of daytime wakefulness and/or psychomotor performance). CNS depressant effects may persist in some patients for up to several days after discontinuing BELSOMRA.

BELSOMRA can impair driving skills and may increase the risk of falling asleep while driving. Discontinue or decrease the dose in patients who drive if daytime somnolence develops. In a study of healthy adults, driving ability was impaired in some individuals taking 20 mg BELSOMRA. Although pharmacodynamic tolerance or adaptation to some adverse depressant effects of BELSOMRA may develop with daily use, patients using the 20 mg dose of BELSOMRA should be cautioned against next-day driving and other activities requiring full mental alertness. Patients taking lower doses of BELSOMRA should also be cautioned about the potential for driving impairment because there is individual variation in sensitivity to BELSOMRA.

Co-administration with other CNS depressants (e.g., benzodiazepines, opioids, tricyclic antidepressants, alcohol) increases the risk of CNS depression. Patients should be advised not to consume alcohol in combination with BELSOMRA because of additive effects. Dosage adjustments of BELSOMRA and of concomitant CNS depressants may be necessary when administered together because of potentially additive effects. The use of BELSOMRA with other drugs to treat insomnia is not recommended.

The risk of next-day impairment, including impaired driving, is increased if BELSOMRA is taken with less than a full night of sleep remaining, if a higher than the recommended dose is taken, if coadministered with other CNS depressants, or if co-administered with other drugs that increase blood levels of BELSOMRA. Patients should be cautioned against driving and other activities requiring complete mental alertness if BELSOMRA is taken in these circumstances.

Because sleep disturbances may be the presenting manifestation of a physical and/or psychiatric disorder, treatment of insomnia should be initiated only after careful evaluation of the patient. The failure of insomnia to remit after 7 to 10 days of treatment may indicate the presence of a primary psychiatric and/or medical illness that should be evaluated. Worsening of insomnia or the emergence of new cognitive or behavioral abnormalities may be the result of an unrecognized underlying psychiatric or physical disorder, and can emerge during the course of treatment with hypnotic drugs such as BELSOMRA.

A variety of cognitive and behavioral changes (e.g., amnesia, anxiety, hallucinations and other neuropsychiatric symptoms) have been reported to occur in association with the use of hypnotics such as BELSOMRA. Complex behaviors such as “sleep-driving” (i.e., driving while not fully awake after taking a hypnotic) and other complex behaviors (e.g., preparing and eating food, making phone calls, or having sex), with amnesia for the event, have been reported in association with the use of hypnotics. These events can occur in hypnotic-naïve as well as in hypnotic-experienced persons. The use of alcohol and other CNS depressants may increase the risk of such behaviors. Discontinuation of BELSOMRA should be strongly considered for patients who report any complex sleep behavior.

In clinical studies, a dose-dependent increase in suicidal ideation was observed in patients taking BELSOMRA as assessed by questionnaire. Immediately evaluate patients with suicidal ideation or any new behavioral sign or symptom.

In primarily depressed patients treated with sedative-hypnotics, worsening of depression, and suicidal thoughts and actions (including completed suicides) have been reported. Suicidal tendencies may be present in such patients and protective measures may be required. Intentional overdose is more common in this group of patients; therefore, the lowest number of tablets that is feasible should be prescribed for the patient at any one time.

The emergence of any new behavioral sign or symptom of concern requires careful and immediate evaluation.

Effect of BELSOMRA on respiratory function should be considered if prescribed to patients with compromised respiratory function. BELSOMRA has not been studied in patients with severe obstructive sleep apnea (OSA) or severe chronic obstructive pulmonary disease (COPD).

Sleep paralysis, an inability to move or speak for up to several minutes during sleep-wake transitions, and hypnagogic/hypnopompic hallucinations, including vivid and disturbing perceptions by the patient, can occur with the use of BELSOMRA. Prescribers should explain the nature of these events to patients when prescribing BELSOMRA.

Symptoms similar to mild cataplexy can occur, with risk increasing with the dose of BELSOMRA. Such symptoms can include periods of leg weakness lasting from seconds to a few minutes, can occur both at night and during the day, and may not be associated with an identified triggering event (e.g., laughter or surprise).

Advise the patient to read the FDA-approved patient labeling (Medication Guide).

Inform patients of the availability of a Medication Guide and instruct them to read the Medication Guide prior to initiating treatment and with each prescription refill. Review the BELSOMRA Medication Guide with every patient prior to initiation of treatment.

Tell patients that BELSOMRA has the potential to cause next-day impairment, and that this risk is increased with higher doses or if dosing instructions are not carefully followed. Patients using the 20 mg dose should be cautioned against next-day driving and other activities requiring full mental alertness as this dose is associated with a higher risk of impaired driving. Patients taking lower doses should also be cautioned about the potential for driving impairment because there is individual variation in sensitivity to BELSOMRA.

Patients should not drive or engage in other activities requiring full alertness within 8 hours of dosing of BELSOMRA.

Instruct patients to inform their families that BELSOMRA has been associated with getting out of bed while not being fully awake, and tell patients and their families to call their healthcare providers if this occurs.

Hypnotics, like BELSOMRA, have been associated with “sleep-driving” and other complex behaviors while not being fully awake (preparing and eating food, making phone calls, or having sex). Tell patients and their families to call their healthcare providers if they develop any of these symptoms.

Tell patients to report any worsening of depression or suicidal thoughts immediately.

Ask patients about alcohol consumption, prescription medicines they are taking, and drugs they may be taking without a prescription. Advise patients not to use BELSOMRA if they drank alcohol that evening or before bed.

Tell patients not to increase the dose of BELSOMRA on their own, and to inform you if they believe the drug “does not work.”

Advise patients to take BELSOMRA only when preparing for or getting into bed and only if they can stay in bed for a full night before being active again. Advise patients to report all of their prescription and nonprescription medicines, vitamins and herbal supplements to the prescriber.

In a 26-week study in Tg.rasH2 mice, there was no evidence of suvorexant-induced neoplasms at oral doses of 25, 50, 200, and 650 mg/kg/day.

In a 2-year study in rats (oral suvorexant doses of 80, 160, and 325 mg/kg/day), increases in thyroid (follicular cell adenoma and combined adenoma/carcinoma in high-dose females; follicular cell adenoma in mid- and high-dose males) and liver (hepatocellular adenoma in high-dose males) neoplasms were observed. These findings were consistent with increased TSH and hepatic enzyme induction, respectively, which are mechanisms believed to be rodent-specific. Plasma exposures (AUC) at doses not associated with drug-induced neoplasms in rats were approximately 7 times that in humans at the maximum recommended human dose (MRHD) of 20 mg.

Suvorexant was negative in in vitro (bacterial reverse mutation and chromosomal aberration) and in vivo (mouse and rat micronucleus) assays.

In two separate studies, male and female rats were treated with suvorexant prior to and during mating and continuing in females to gestation day 7. Increases in peri-implantation loss and resorptions, resulting in a decrease in live fetuses, were observed at the highest doses tested (1200 or 325 mg/kg) when treated males and females were mated with untreated animals. At the no-effect dose for adverse effects on Suvorexant 4 0 mg was evaluated in all studies, except midazolam where 80 mg suvorexant was administered.

There are no adequate and well-controlled studies in pregnant women. BELSOMRA should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Administration of suvorexant to pregnant rats throughout organogenesis in two separate studies at oral doses of 30, 150, and 1000 mg/kg or 30, 80, and 325 mg/kg resulted in a decrease in fetal body weight at doses greater than 80 mg/kg. Plasma exposures (AUC) at the no-effect dose were approximately 25 times that in humans at the maximum recommended human dose (MRHD) of 20 mg/day.

Administration of suvorexant to pregnant rabbits throughout organogenesis in two separate studies at oral doses of 40, 100, and 300 mg/kg or 50, 150, and 325 mg/kg resulted in no apparent adverse effects on embryo-fetal development. Excessive toxicity resulted in premature sacrifice of pregnant animals at 325 mg/kg. The highest maternal plasma exposures (AUC) for which there are fetal data were up to approximately 40 times that in humans at the MRHD.

Administration of suvorexant (oral doses of 30, 80, and 200 mg/kg) to pregnant rats throughout gestation and lactation resulted in decreased body weight in offspring at the highest dose tested. Plasma AUCs at the no-effect dose were approximately 25 times that in humans at the MRHD.

Suvorexant and a hydroxyl-suvorexant metabolite were excreted in rat milk at levels higher (9 and 1.5 times, respectively) than that in maternal plasma. It is not known whether this drug is secreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when BELSOMRA is administered to a nursing woman.

Safety and effectiveness in pediatric patients have not been established.

Of the total number of patients treated with BELSOMRA (n=1784) in controlled clinical safety and efficacy studies, 829 patients were 65 years and over, and 159 patients were 75 years and over. No clinically meaningful differences in safety or effectiveness were observed between these patients and younger patients at the recommended doses.

Effects of BELSOMRA on respiratory function should be considered if prescribed to patients with compromised respiratory function.

The respiratory depressant effect of BELSOMRA was evaluated after one night and after four consecutive nights of treatment in a randomized, placebo-controlled, 2-period crossover study in patients (n=26) with mild to moderate obstructive sleep apnea. Following once-daily doses of 40 mg, the mean Apnea/Hypopnea Index treatment difference (suvorexant – placebo) on Day 4 was 2.7 (90% CI: 0.22 to 5.09), but there was wide inter- and intra-individual variability such that clinically meaningful respiratory effects of BELSOMRA in obstructive sleep apnea cannot be excluded. BELSOMRA has not been studied in patients with severe obstructive sleep apnea.

The respiratory depressant effect of BELSOMRA was evaluated after one night and after four consecutive nights of treatment in a randomized, placebo-controlled, 2-period crossover study in patients (n=25) with mild to moderate chronic obstructive pulmonary disease (COPD). BELSOMRA (40 mg in non-elderly, 30 mg in elderly) had no respiratory depressant effects in patients with mild to moderate COPD, as measured by oxygen saturation. There was wide inter- and intra-individual variability such that clinically meaningful respiratory effects of BELSOMRA in COPD cannot be excluded. BELSOMRA has not been studied in patients with severe COPD.

No dose adjustment is required in patients with mild and moderate hepatic impairment. BELSOMRA has not been studied in patients with severe hepatic impairment and is not recommended for these patients.

No dose adjustment is required in patients with renal impairment.

Dosage (Posology) and method of administration

Use the lowest dose effective for the patient.

The recommended dose for BELSOMRA is 10 mg, taken no more than once per night and within 30 minutes of going to bed, with at least 7 hours remaining before the planned time of awakening. If the 10 mg dose is well-tolerated but not effective, the dose can be increased. The maximum recommended dose of BELSOMRA is 20 mg once daily.

Exposure to BELSOMRA is increased in obese compared to non-obese patients, and in women compared to men. Particularly in obese women, the increased risk of exposure-related adverse effects should be considered before increasing the dose.

When BELSOMRA is combined with other CNS depressant drugs, dosage adjustment of BELSOMRA and/or the other drug(s) may be necessary because of potentially additive effects.

The recommended dose of BELSOMRA is 5 mg when used with moderate CYP3A inhibitors and the dose generally should not exceed 10 mg in these patients. BELSOMRA is not recommended for use with strong CYP3A inhibitors.

Time to effect of BELSOMRA may be delayed if taken with or soon after a meal.

Interaction with other medicinal products and other forms of interaction

An additive effect on psychomotor performance was observed when a single dose of 40 mg of suvorexant was co-administered with a single dose of 0.7 g/kg alcohol. Suvorexant did not affect alcohol concentrations and alcohol did not affect suvorexant concentrations.

An interaction study with a single dose of 40 mg suvorexant and paroxetine 20 mg at steady-state levels in healthy subjects did not demonstrate a clinically significant pharmacokinetic or pharmacodynamic interaction.

The effects of other drugs on the pharmacokinetics of suvorexant are presented in Figure 1 as change relative to suvorexant administered alone (test/reference). Strong (e.g., ketoconazole or itraconazole) and moderate (e.g., diltiazem) CYP3A inhibitors significantly increased suvorexant exposure. Strong CYP3A inducers (e.g., rifampin) substantially decreased suvorexant exposure.

Figure 1: Effects of Co-administered Drugs on the Pharmacokinetics of Suvorexant

In vitro metabolism studies demonstrate that suvorexant has the potential to inhibit CYP3A and intestinal P-gp; however, suvorexant is unlikely to cause clinically significant inhibition of human CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19 or CYP2D6. In addition, no clinically meaningful inhibition of OATP1B1, BCRP and OCT2 transporters is anticipated. Chronic administration of suvorexant is unlikely to induce the metabolism of drugs metabolized by major CYP isoforms. Specific in vivo effects on the pharmacokinetics of midazolam, warfarin, digoxin and oral contraceptives are presented in Figure 2 as a change relative to the interacting drug administered alone (test/reference).

Figure 2: Effects of Suvorexant* on the Pharmacokinetics of Co-administered Drugs

# Monitor digoxin concentrations as clinically indicated .
*Suvorexant 4 0 mg was evaluated in all studies, except midazolam where 80 mg suvorexant was administered.