(binimetinib)

Prescribing Information
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12 CLINICAL PHARMACOLOGY

12 CLINICAL PHARMACOLOGY

12.1 Mechanism of Action

Binimetinib is a reversible inhibitor of mitogen-activated extracellular signal regulated kinase 1 (MEK1) and MEK2 activity. MEK proteins are upstream regulators of the extracellular signal-related kinase (ERK) pathway. In vitro, binimetinib inhibited extracellular signal-related kinase (ERK) phosphorylation in cell-free assays as well as viability and MEK-dependent phosphorylation of BRAF-mutant human melanoma cell lines. Binimetinib also inhibited in vivo ERK phosphorylation and tumor growth in BRAF-mutant murine xenograft models.

Binimetinib and encorafenib target two different kinases in the RAS/RAF/MEK/ERK pathway. Compared to either drug alone, coadministration of encorafenib and binimetinib resulted in greater anti-proliferative activity in vitro in BRAF mutation-positive cell lines and greater anti-tumor activity with respect to tumor growth inhibition in BRAF V600E mutant human melanoma xenograft studies in mice. Additionally, the combination of binimetinib and encorafenib delayed the emergence of resistance in BRAF V600E mutant human melanoma xenografts in mice compared to either drug alone. In a BRAF V600E mutant NSCLC patient-derived xenograft model in mice, coadministration of encorafenib and binimetinib resulted in greater anti-tumor activity compared to binimetinib alone, with respect to tumor growth inhibition. Increased tumor growth delay after dosing cessation was also observed with the coadministration compared to either drug alone.

12.2 Pharmacodynamics

Cardiac Electrophysiology

Following MEKTOVI 45 mg twice daily, no clinically meaningful QT prolongation was observed.

12.3 Pharmacokinetics

The pharmacokinetics of binimetinib was studied in healthy subjects and patients with solid tumors. After twice-daily dosing, the accumulation is 1.5-fold and the coefficient of variation (CV%) of the area under the concentration-time curve (AUC) is <40% at steady state. The systemic exposure of binimetinib is approximately dose proportional.

Absorption

After oral administration, at least 50% of the binimetinib dose was absorbed with a median time to maximum concentration (Tmax) of 1.6 hours.

Effect of Food

The administration of a single dose of MEKTOVI 45 mg with a high-fat, high-calorie meal (consisting of approximately 150 calories from protein, 350 calories from carbohydrate, and 500 calories from fat) in healthy subjects had no effect on binimetinib exposure.

Distribution

Binimetinib is 97% bound to human plasma proteins and the blood-to-plasma ratio is 0.72. The geometric mean (CV%) of apparent volume of distribution of binimetinib is 92 L (45%).

Elimination

The mean (CV%) terminal half-life (t1/2) of binimetinib is 3.5 hours (28.5%) and apparent clearance (CL/F) is 20.2 L/h (24%).

Metabolism

The primary metabolic pathway is glucuronidation with UGT1A1 contributing up to 61% of the binimetinib metabolism. Other pathways of binimetinib metabolism include N-dealkylation, amide hydrolysis, and loss of ethane-diol from the side chain. The active metabolite M3 produced by CYP1A2 and CYP2C19 represents 8.6% of the binimetinib exposure. Following a single oral dose of 45 mg radiolabeled binimetinib, approximately 60% of the circulating radioactivity AUC in plasma was attributable to binimetinib.

Excretion

Following a single oral dose of 45 mg radiolabeled binimetinib in healthy subjects, 62% (32% unchanged) of the administered dose was recovered in the feces while 31% (6.5% unchanged) was recovered in the urine.

Specific Populations

Age (20 to 94 years), sex, or body weight do not have a clinically important effect on the systemic exposure of binimetinib. The effect of race or ethnicity on the pharmacokinetics of binimetinib is unknown.

Hepatic Impairment: No clinically meaningful changes in binimetinib exposure (AUC and Cmax) were observed in subjects with mild hepatic impairment (total bilirubin >1 and ≤1.5 × ULN and any AST or total bilirubin ≤ ULN and AST > ULN) as compared to subjects with normal liver function (total bilirubin ≤ ULN and AST ≤ ULN). A 2-fold increase in AUC was observed in subjects with moderate (total bilirubin >1.5 and ≤3 × ULN and any AST) or severe (total bilirubin levels >3 × ULN and any AST) hepatic impairment [see Dosage and Administration (2.4)].

Renal Impairment: In subjects with severe renal impairment (eGFR ≤29 mL/min/1.73 m2), no clinically important changes in binimetinib exposure were observed as compared to subjects with normal renal function.

Drug Interaction Studies

Clinical Studies

Effect of UGT1A1 Inducers or Inhibitors on Binimetinib: UGT1A1 genotype and smoking (UGT1A1 inducer) do not have a clinically important effect on binimetinib exposure. Simulations predict similar Cmax of binimetinib 45 mg in the presence or absence of atazanavir 400 mg (UGT1A1 inhibitor).

No differences in binimetinib exposure have been observed when MEKTOVI is coadministered with encorafenib.

Effect of Binimetinib on CYP Substrates: Binimetinib did not alter the exposure of a sensitive CYP3A4 substrate (midazolam).

Effect of Acid Reducing Agents on Binimetinib: The extent of binimetinib exposure (AUC) was not altered in the presence of a gastric acid reducing agent (rabeprazole).

In Vitro Studies

Effect of Binimetinib on CYP Substrates: Binimetinib is not a time-dependent inhibitor of CYP1A2, CYP2C9, CYP2D6 or CYP3A.

Effect of Transporters on Binimetinib: Binimetinib is a substrate of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP). Binimetinib is not a substrate of organic anion transporting polypeptide (OATP1B1, OATP1B3, OATP2B1) or organic cation transporter 1 (OCT1).

Medication Guide

MEDICATION GUIDE

     

MEDICATION GUIDE

MEKTOVI® (mek-TOE-vee)

(binimetinib)

tablets

Important Information: If your healthcare provider prescribes MEKTOVI with encorafenib, please read the Medication Guide that comes with encorafenib.

What is the most important information I should know about MEKTOVI when taken in combination with encorafenib?

MEKTOVI when taken in combination with encorafenib may cause serious side effects, including:

•
Risk of new skin cancers. MEKTOVI, when used with encorafenib, may cause skin cancers called cutaneous squamous cell carcinoma or basal cell carcinoma.
 
Talk to your healthcare provider about your risk for these cancers.
 
Check your skin and tell your healthcare provider right away about any skin changes, including a:
o
new wart
o
skin sore or reddish bump that bleeds or does not heal
o
change in size or color of a mole
 
Your healthcare provider should check your skin before treatment with MEKTOVI, when taken in combination with encorafenib, every 2 months during treatment, and for up to 6 months after you stop treatment to look for any new skin cancers.
 
Your healthcare provider should also check for cancers that may not occur on the skin. Tell your healthcare provider about any new symptoms that develop during treatment with MEKTOVI when taken in combination with encorafenib.

See "What are the possible side effects of MEKTOVI?" for more information about side effects.

What is MEKTOVI?

MEKTOVI is a prescription medicine used:

•
in combination with a medicine called encorafenib to treat people with a type of skin cancer called melanoma:
o
that has spread to other parts of the body or cannot be removed by surgery, and
o
that has a certain type of abnormal “BRAF” gene
•
in combination with a medicine called encorafenib to treat adults with a type of lung cancer called non-small cell lung cancer (NSCLC):
o
that has spread to other parts of the body, and
o
that has a certain type of abnormal “BRAF” gene

Your healthcare provider will perform a test to make sure that MEKTOVI is right for you.

It is not known if MEKTOVI is safe and effective in children.

Before taking MEKTOVI, tell your healthcare provider about all of your medical conditions, including if you:

•
have heart problems
•
have had blood clots
•
have eye problems
•
have lung or breathing problems
•
have liver or kidney problems
•
have any muscle problems
•
have bleeding problems
•
have high blood pressure (hypertension)
•
are pregnant or plan to become pregnant. MEKTOVI can harm your unborn baby.
o
Females who are able to become pregnant should use effective birth control (contraception) during treatment with MEKTOVI and for at least 30 days after the last dose of MEKTOVI.
o
Talk to your healthcare provider about birth control methods that may be right for you during this time.
o
Your healthcare provider will do a pregnancy test before you start taking MEKTOVI. Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with MEKTOVI.
•
are breastfeeding or plan to breastfeed. It is not known if MEKTOVI passes into your breast milk. Do not breastfeed during treatment with MEKTOVI and for 3 days after the last dose of MEKTOVI. Talk to your healthcare provider about the best way to feed your baby during this time.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

How should I take MEKTOVI?

•
Take MEKTOVI exactly as your healthcare provider tells you to take it. Do not change your dose or stop taking MEKTOVI unless your healthcare provider tells you to.
•
Take MEKTOVI in combination with encorafenib by mouth 2 times a day, about 12 hours apart.
•
MEKTOVI may be taken with or without food.
•
If you miss a dose of MEKTOVI, take it as soon as you remember. If it is within 6 hours of your next scheduled dose, take your next dose at your regular time. Do not make up for the missed dose.
•
Do not take an extra dose if you vomit after taking your scheduled dose. Take your next dose at your regular time.
•
If you stop treatment with encorafenib, talk to your healthcare provider about whether your MEKTOVI treatment may need to be stopped.

What are the possible side effects of MEKTOVI?

MEKTOVI may cause serious side effects, including:

•
Heart problems, including heart failure. MEKTOVI, when taken with encorafenib, can cause heart problems. Your healthcare provider should check your heart function before and during treatment with MEKTOVI. Call your healthcare provider right away if you have any of the following signs and symptoms of a heart problem:
o
feeling like your heart is pounding or racing
o
shortness of breath
o
swelling of your ankles and feet
o
feeling lightheaded
•
Blood clots. MEKTOVI, when taken with encorafenib, can cause blood clots in your arms or legs, which can travel to your lungs and can lead to death. Get medical help right away if you have the following symptoms:
o
chest pain
o
sudden shortness of breath or trouble breathing
o
pain in your legs with or without swelling
o
swelling in your arms and legs
o
a cool pale arm or leg
•
Eye problems. MEKTOVI, when taken with encorafenib, can cause eye problems. Your healthcare provider should perform an eye exam regularly during treatment with MEKTOVI. Tell your healthcare provider right away if you develop any new or worsening symptoms of eye problems, including:
o
blurred vision, loss of vision, or other vision changes
o
see colored dots
o
see halos (blurred outline around objects)
o
eye pain, swelling, or redness
•
Lung or breathing problems. MEKTOVI, when taken with encorafenib, can cause lung or breathing problems. Tell your healthcare provider if you have any new or worsening symptoms of lung or breathing problems, including:
o
shortness of breath
o
cough
•
Liver problems. MEKTOVI, when taken with encorafenib, can cause liver problems. Your healthcare provider should perform blood tests to check your liver function before and during treatment with MEKTOVI. Tell your healthcare provider if you have any of the following signs and symptoms of a liver problem:
o
yellowing of your skin or your eyes
o
dark or brown (tea-colored) urine
o
nausea or vomiting
o
loss of appetite
o
tiredness
o
bruising
o
bleeding
•
Muscle problems (rhabdomyolysis). MEKTOVI, when taken with encorafenib, can cause muscle problems that can be severe. Treatment with MEKTOVI may increase the level of an enzyme in your blood called creatine phosphokinase (CPK) and can be a sign of muscle damage. Your healthcare provider should perform a blood test to check your levels of CPK before and during treatment. Tell your healthcare provider right away if you develop any of these symptoms:
o
weakness
o
muscle aches or pain
o
dark, reddish urine
•
Bleeding problems. MEKTOVI, when taken with encorafenib, can cause serious bleeding problems, including in your brain or stomach, that can lead to death. Tell your healthcare provider and get medical help right away if you develop any signs of bleeding, including:
o
headaches, dizziness, or feeling weak
o
cough up blood or blood clots
o
vomit blood or your vomit looks like “coffee grounds”
o
red or black stool that look like tar

Your healthcare provider may change your dose, temporarily stop, or permanently stop treatment with MEKTOVI if you have certain side effects.

The most common side effects of MEKTOVI when taken with encorafenib for melanoma include:

•
fatigue
•
nausea
•
diarrhea
•
vomiting
•
stomach-area (abdominal) pain

The most common side effects of MEKTOVI when taken with encorafenib for NSCLC include:

•
fatigue
•
nausea
•
diarrhea
•
muscle or joint pain
•
vomiting
•
stomach-area (abdominal) pain
•
blurred vision, loss of vision, or other vision changes
•
constipation
•
shortness of breath
•
rash
•
cough

These are not all of the possible side effects of MEKTOVI.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

You may also report side effects to Pfizer Inc. at 1-800-438-1985.

How should I store MEKTOVI?

•
Store MEKTOVI at room temperature between 68°F to 77°F (20°C to 25°C).

Keep MEKTOVI and all medicines out of the reach of children.

General information about the safe and effective use of MEKTOVI.

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use MEKTOVI for a condition for which it was not prescribed. Do not give MEKTOVI to other people, even if they have the same symptoms that you have. It may harm them. You can ask your healthcare provider or pharmacist for information about MEKTOVI that is written for health professionals.

What are the ingredients in MEKTOVI?

Active ingredient: binimetinib

Inactive ingredients: lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, magnesium stearate (vegetable source), and colloidal silicon dioxide

Tablet coating: polyvinyl alcohol, polyethylene glycol, titanium dioxide, talc, ferric oxide yellow, ferrosoferric oxide

Distributed by: Array BioPharma Inc., a wholly owned subsidiary of Pfizer Inc., Boulder, Colorado 80301.

MEKTOVI® is a registered trademark of Array BioPharma Inc. in the United States and various other countries.

For more information, go to www.BRAFTOVIMEKTOVI.com or call 1-844-792-7729.

©2020 Array BioPharma Inc. All rights reserved.

LAB-1427-2.0

This Medication Guide has been approved by the U.S. Food and Drug Administration.
Revised: 10/2023

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