QuilliChew ER

The FDA has approved Quillichew ER methylphenidate hydrochloride; pfizer) extended-release chewable tablets (Schedule II) for the treatment of attention-deficit/hyperactivity disorder (ADHD) in patients 6 years and older.¹ Approximately 11% of American children aged 4 to 17 years have been given a diagnosis of ADHD at some point in their lives, according to the CDC’s 2011 data. Patients with ADHD demonstrate symptoms such as inattention, impulsivity, and being overly active. In some patients, the condition may continue into adulthood.²

PHARMACOLOGY AND PHARMACOKINETICS

Methylphenidate is a central nervous system (CNS) stimulant. It is believed to block the reuptake of norepinephrine and dopamine into the presynaptic neuron and increase the release of these monoamines into the extraneuronal space.

After fasting, a single oral dose of QuilliChew ER 40 mg reached C_max at a median time of 5 hours after dosing. Compared with an immediate-release formulation of methylphenidate 40 mg, the QuilliChew ER mean peak concentration was about 20% lower and exposure was about 11% lower. The mean elimination half-life of QuilliChew ER is about 5.2 hours after a 40-mg dose.¹

DOSAGE AND ADMINISTRATION

Patients 6 years and older should begin treatment with QuilliChew ER at a dose of 20 mg once daily in the morning. The dosage may be increased weekly in increments of 10, 15, or 20 mg per day. A daily dose above 60 mg per day is not recommended. QuilliChew ER may be taken without regard to food.¹

CLINICAL TRIALS

The efficacy of QuilliChew ER was evaluated in a double-blind, randomized, placebo-controlled, parallel group laboratory classroom study of 90 children aged 6 to 12 years with a diagnosis of ADHD. Laboratory classroom raters and teachers evaluated the attention and behavior of the children throughout the day using the Swanson, Kotkin, Agler, M-Flynn, and Pelham (SKAMP) rating scale, which is a validated 13-item teacher-rated scale that assesses manifestations of ADHD in a classroom setting. The SKAMP-combined score, which was measured at 0.75, 2, 4, 8, 10, 12, and 13 hours after dosing, was used to assess the primary and the key secondary efficacy parameters. The primary efficacy end point was the average of treatment effects across all the time points in which QuilliChew ER was statistically significantly superior to placebo. The key secondary efficacy parameters were onset and duration of clinical effect in which QuilliChew ER showed improvement over placebo at 0.75, 2, 4, and 8 hours after dosing.^1,2

CONTRAINDICATIONS, WARNINGS, AND PRECAUTIONS

QuilliChew ER carries a boxed warning regarding the high potential for abuse and dependence of CNS stimulants, methylphenidate-containing products, and amphetamines. The risk of abuse should be assessed prior to the initiation of treatment with QuilliChew ER, and the patient should be monitored for signs of abuse and dependence throughout therapy.

QuilliChew ER is contraindicated in patients with a known hypersensitivity to methylphenidate or to any of the components of the medication. It is also contraindicated during concurrent treatment with a monoamine oxidase inhibitor or use of one within the previous 14 days.

Serious cardiovascular reactions have occurred in patients using CNS stimulants at recommended doses. CNS stimulants cause an increase in blood pressure and heart rate; therefore, patients should be monitored accordingly. Use of CNS stimulants may also cause psychotic or manic symptoms in patients without prior history of either condition; therefore, patients should be evaluated for bipolar disorder prior to initiation of treatment. Priapism has been reported during treatment with methylphenidate products. CNS stimulants used for the treatment of ADHD are also associated with peripheral vasculopathy, including Raynaud’s phenomenon. Pediatric patients should have their height and weight monitored at appropriate intervals, as CNS stimulants have been associated with growth suppression. QuilliChew ER contains phenylalanine, which may be harmful to patients with phenylketonuria.

The most common adverse reactions (≥5%, and twice the rate of placebo) are decreased appetite, insomnia, nausea, vomiting, dyspepsia, abdominal pain, weight loss, anxiety, dizziness, irritability, affect lability, tachycardia, and increase in blood pressure.¹

Dr. Holmberg earned her PharmD from the University of Connecticut and completed an ambulatory care residency at the Phoenix VA Healthcare System. Her practice has also included pediatrics and inpatient mental health. She resides in Phoenix, Arizona.

References

• QuilliChew ER [package insert]. New York, NY: Pfizer; 2016.
• Pfizer receives US FDA approval of new QuilliChew ER (methylphenidate hydrochloride) extended-release chewable tablets CII [news release]. Pfizer Inc; December 7, 2015. pfizer.com/news/press-release/press-release-detail/pfizer_receives_u_s_fda_approval_of_new_QuilliChew_er_methylphenidate_hydrochloride_extended_release_chewable_tablets_cii. Accessed April 2016.