phentermine and topiramate

Contraindications ( 4 ) 03/2026 Warnings and Precautions ( 5.13 , 5.15 ) 03/2026

1 INDICATIONS AND USAGE Phentermine and topiramate extended-release capsules are indicated in combination with a reduced-calorie diet and increased physical activity to reduce excess body weight and maintain weight reduction long term in: Adults and pediatric patients aged 12 years and older with obesity Adults with overweight in the presence of at least one weight-related comorbid condition Limitations of Use The effect of phentermine and topiramate extended-release capsules on cardiovascular morbidity and mortality has not been established. The safety and effectiveness of phentermine and topiramate extended-release capsules in combination with other products intended for weight loss, including prescription drugs, over-the-counter drugs, and herbal preparations, have not been established. Phentermine and topiramate extended-release capsules are a combination of phentermine, a sympathomimetic amine anorectic, and topiramate, indicated in combination with a reduced-calorie diet and increased physical activity to reduce excess body weight and maintain weight reduction long term in: Adults and pediatric patients aged 12 years and older with obesity ( 1 ). Adults with overweight in the presence of at least one weight-related comorbid condition ( 1 ). Limitations of Use: The effect of phentermine and topiramate extended-release capsules on cardiovascular morbidity and mortality has not been established ( 1 ). The safety and effectiveness of phentermine and topiramate extended-release capsules in combination with other products intended for weight loss, including prescription and over-the-counter drugs, and herbal preparations, have not been established ( 1 ).

2 DOSAGE AND ADMINISTRATION Take orally once daily in morning. Avoid administration in evening to prevent insomnia ( 2.2 ). Recommended starting dosage is 3.75 mg/23 mg (phentermine mg/topiramate mg) daily for 14 days; then increase to 7.5 mg/46 mg daily ( 2.2 ). Escalate dosage based on weight loss in adults or BMI reduction in pediatric patients. See the Full Prescribing Information for details regarding discontinuation or dosage escalation ( 2.2 ). Gradually discontinue 15 mg/92 mg dosage to prevent possible seizure ( 2.3 ). Do not exceed 7.5 mg/46 mg dosage for patients with moderate or severe renal impairment or patients with moderate hepatic impairment ( 2.4 , 2.5 ). 2.1 Recommended Testing Prior to and During Treatment with Phentermine and Topiramate Extended-Release Capsules Prior to phentermine and topiramate extended-release capsule initiation and during treatment with phentermine and topiramate extended-release capsules, the following is recommended: Obtain a negative pregnancy test before initiating phentermine and topiramate extended-release capsules in patients who can become pregnant and monthly during phentermine and topiramate extended-release capsule therapy. Phentermine and topiramate extended-release capsules are contraindicated during pregnancy [see Contraindications ( 4 ), Warnings and Precautions ( 5.1 ), and Use in Specific Populations ( 8.3 )] . Obtain a blood chemistry profile that includes bicarbonate, creatinine, and potassium in all patients, and glucose in patients with type 2 diabetes mellitus on antidiabetic medication prior to initiating phentermine and topiramate extended-release capsule treatment and periodically during treatment [see Warnings and Precautions ( 5.7 , 5.8 , 5.12 )] . 2.2 Recommended Dosage and Administration The recommended dosage, titration, and administration of phentermine and topiramate extended-release capsules are as follows: Take phentermine and topiramate extended-release capsules orally once daily in the morning with or without food. Avoid administration of phentermine and topiramate extended-release capsules in the evening due to the possibility of insomnia. The recommended starting dosage of phentermine and topiramate extended-release capsules is one capsule (containing 3.75 mg of phentermine and 23 mg of topiramate) (3.75 mg/23 mg) taken orally once daily for 14 days; after 14 days increase to the recommended dosage of phentermine and topiramate extended-release capsules 7.5 mg/46 mg orally once daily. After 12 weeks of treatment with phentermine and topiramate extended-release capsules 7.5 mg/46 mg, evaluate weight loss for adults or BMI reduction for pediatric patients aged 12 years and older. If an adult patient has not lost at least 3% of baseline body weight or a pediatric patient has not experienced a reduction of at least 3% of baseline BMI, increase the dosage to phentermine and topiramate extended-release capsules 11.25 mg/69 mg orally once daily for 14 days; followed by an increase in the dosage to phentermine and topiramate extended-release capsules 15 mg/92 mg orally once daily. After 12 weeks of treatment with phentermine and topiramate extended-release capsules 15 mg/92 mg, evaluate weight loss for adults or BMI reduction for pediatric patients aged 12 years and older. If an adult patient has not lost at least 5% of baseline body weight or a pediatric patient has not experienced a reduction of at least 5% of baseline BMI, discontinue phentermine and topiramate extended-release capsules [see Dosage and Administration ( 2.3 )] , as it is unlikely that the patient will achieve and sustain clinically meaningful weight loss with continued treatment. Monitor the rate of weight loss in pediatric patients. If weight loss exceeds 2 lbs (0.9 kg)/week, consider dosage reduction. 2.3 Discontinuation of Phentermine and Topiramate Extended-Release Capsules 15 mg/92 mg Discontinue phentermine and topiramate extended-release capsules 15 mg/92 mg gradually by taking p …

3 DOSAGE FORMS AND STRENGTHS Phentermine and topiramate extended-release capsules are available in four strengths (phentermine mg/topiramate mg): 3.75 mg/23 mg - White opaque cap printed with WPI, orange opaque body printed with 2196 7.5 mg/46 mg - White opaque cap printed with WPI, green opaque body printed with 2195 11.25 mg/69 mg - Light yellow opaque cap printed with WPI, white opaque body printed with 2299 15 mg/92 mg - White opaque cap printed with WPI, dark scarlet opaque body printed with 2194 Extended-release capsules: (phentermine mg/topiramate mg) 3.75 mg/23 mg ( 3 ) 7.5 mg/46 mg ( 3 ) 11.25 mg/69 mg ( 3 ) 15 mg/92 mg ( 3 )

4 CONTRAINDICATIONS Phentermine and topiramate extended-release capsules are contraindicated in patients: Who are pregnant [see Warnings and Precautions ( 5.1 ) and Use in Specific Populations ( 8.1 )] With glaucoma [see Warnings and Precautions ( 5.3 )] With hyperthyroidism Taking or within 14 days of stopping a monoamine oxidase inhibitors [see Drug Interactions ( 7 )] With known hypersensitivity to phentermine, topiramate or any of the excipients in phentermine and topiramate extended-release capsules, or idiosyncrasy to the sympathomimetic amines. Anaphylaxis and angioedema have occurred with topiramate [see Warnings and Precautions (5.15)] . Pregnancy ( 4 ) Glaucoma ( 4 ) Hyperthyroidism ( 4 ) Taking or within 14 days of stopping monoamine oxidase inhibitors ( 4 ) Known hypersensitivity to any component of phentermine and topiramate extended-release capsules or idiosyncrasy to sympathomimetic amines ( 4 )

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Embryo-Fetal Toxicity [ see Warnings and Precautions (5.1) and Use in Specific Populations (8.1 , 8.6) ] Suicidal Behavior and Ideation [see Warnings and Precautions (5.2) ] Risk of Ophthalmologic Adverse Reactions [see Warnings and Precautions (5.3) ] Mood and Sleep Disorders [see Warnings and Precautions (5.4) ] Cognitive Impairment [see Warnings and Precautions (5.5) ] Slowing of Linear Growth [see Warnings and Precautions (5.6) ] Metabolic Acidosis [see Warnings and Precautions (5.7) ] Decrease in Renal Function [see Warnings and Precautions (5.8) ] Risk of Seizures with Abrupt Withdrawal of phentermine and topiramate extended-release capsules [see Warnings and Precautions (5.9) ] Kidney Stones [see Warnings and Precautions (5.10) ] Oligohydrosis and Hyperthermia [see Warnings and Precautions (5.11) ] Hypokalemia [see Warnings and Precautions (5.12) ] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity Reactions [ see Warnings and Precautions (5.13) ] Serious Skin Reactions [ see Warnings and Precautions (5.14) ] Anaphylaxis and Angioedema [ see Warnings and Precautions (5.15) ] Allergic Reactions Due to Inactive Ingredients FD&C Yellow No. 5 [see Warnings and Precautions (5.16) ] Most common adverse reactions in: Adults (incidence ≥ 5% and at least 1.5 times placebo) are: paraesthesia, dizziness, dysgeusia, insomnia, constipation, and dry mouth ( 6.1 ). Pediatric patients aged 12 years and older (incidence ≥4% and greater than placebo) are: depression, dizziness, arthralgia, pyrexia, influenza, and ligament sprain ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact VIVUS LLC, at 1-888-998-4887 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience 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 studies of another drug and may not reflect the rates observed in practice. The data described herein reflect exposure to phentermine and topiramate extended-release capsules in two 1-year, randomized, double-blind, placebo-controlled, multicenter clinical trials and two supportive trials in 2,318 adult patients with overweight or obesity [936 (40%) patients with hypertension, 309 (13%) patients with type 2 diabetes mellitus, 808 (35%) patients with BMI greater than 40 kg/m 2 ] exposed for a mean duration of 298 days. Data in this section also describe adverse reactions from a 1-year, randomized, double-blind, placebo-controlled multicenter clinical trial that evaluated 223 pediatric patients (12 to 17 years old) with obesity [see Clinical Studies (14) ] . Adults Adverse reactions occurring at greater than or equal to 5% and at least 1.5 times placebo in adults include paraesthesia, dizziness, dysgeusia, insomnia, constipation, and dry mouth. Adverse reactions reported in greater than or equal to 2% of phentermine and topiramate extended-release capsule-treated adults and more frequently than in the placebo group are shown in Table 1 . Table 1. Adverse Reactions Reported in ≥2% of Phentermine and Topiramate Extended-Release Capsule-Treated Adults with Overweight or Obesity and More Frequently than Placebo in Overall Study Population of 1 Year Duration Adverse Reaction Placebo (N = 1561) % Phentermine and Topiramate Extended- Release Capsules 3.75 mg/23 mg (N = 240) % Phentermine and Topiramate Extended- Release Capsules 7.5 mg/46 mg (N = 498) % Phentermine and Topiramate Extended- Release Capsules 15 mg/92 mg (N = 1,580) % Paraesthesia 2 4 14 20 Dry Mouth 3 7 14 19 Constipation 6 8 15 16 Upper Respiratory Tract Infection 13 16 12 14 Headache 9 10 7 11 Dysgeusia 1 1 7 9 Insomnia 5 5 6 9 Nasopharyngitis 8 13 11 9 Dizziness 3 3 7 9 Sinusitis 6 8 7 8 Nausea 4 6 4 7 Back Pain 5 5 6 7 Fatigue 4 5 4 6 Diarrhea 5 5 6 6 …

7 DRUG INTERACTIONS Table 5 displays clinically significant drug interactions with phentermine and topiramate extended-release capsules. Table 5. Clinically Significant Drug Interactions with Phentermine and Topiramate Extended-Release Capsules Monoamine Oxidase Inhibitors Clinical Impact Concomitant use of phentermine with monoamine oxidase inhibitors (MAOIs) increases the risk of hypertensive crisis. Intervention Concomitant use of phentermine and topiramate extended-release capsules is contraindicated during MAOI treatment and within 14 days of stopping an MAOI. Oral Contraceptives Clinical Impact Coadministration of multiple-dose phentermine and topiramate extended-release capsules 15 mg/92 mg once daily with a single dose of oral contraceptive containing 35 mcg ethinyl estradiol (estrogen component) and 1 mg norethindrone (progestin component), in obese otherwise healthy volunteers, decreased the exposure of ethinyl estradiol by 16% and increased the exposure of norethindrone by 22% [see Clinical Pharmacology ( 12.3 )] . Although this interaction is not anticipated to increase the risk of pregnancy, irregular bleeding (spotting) may occur more frequently due to both the increased exposure to the progestin and lower exposure to the estrogen, which tends to stabilize the endometrium. Intervention Inform patients not to discontinue their combination oral contraceptive if spotting occurs, but to notify their health care provider if the spotting is troubling to them. CNS Depressants Including Alcohol Clinical Impact The concomitant use of alcohol or CNS depressant drugs (e.g., barbiturates, benzodiazepines, and sleep medications) with phentermine or topiramate may potentiate CNS depression such as dizziness or cognitive adverse reactions, or other centrally mediated effects of these agents. Intervention Advise patients not to drive or operate machinery until they have gained sufficient experience on phentermine and topiramate extended-release capsules to gauge whether it adversely affects their mental performance, motor performance, and/or vision. Caution patients against excessive alcohol intake when taking phentermine and topiramate extended-release capsules. Consider phentermine and topiramate extended-release capsule dosage reduction or discontinuation if cognitive dysfunction persists [see Warnings and Precautions ( 5.5 )] . Non-Potassium Sparing Diuretics Clinical Impact Concurrent use of phentermine and topiramate extended-release capsules with non-potassium sparing diuretics may potentiate the potassium-wasting action of these diuretics. Concomitant administration of hydrochlorothiazide alone with topiramate alone has been shown to increase the C max and AUC of topiramate by 27% and 29%, respectively. Intervention When phentermine and topiramate extended-release capsules are used concomitantly with non-potassium-sparing diuretics, measure potassium before and during phentermine and topiramate extended-release capsule treatment [see Warnings and Precautions ( 5.12 ) and Clinical Pharmacology ( 12.3 )] . Antiepileptic Drugs Clinical Impact Concomitant administration of phenytoin or carbamazepine with topiramate in patients with epilepsy, decreased plasma concentrations of topiramate by 48% and 40%, respectively, when compared to topiramate given alone [see Clinical Pharmacology ( 12.3 )] . Concomitant administration of valproic acid and topiramate has been associated with hyperammonemia with and without encephalopathy. Concomitant administration of topiramate with valproic acid in patients has also been associated with hypothermia (with and without hyperammonemia). Intervention Consider measuring blood ammonia in patients in whom the onset of hypothermia or encephalopathy has been reported [see Clinical Pharmacology ( 12.3 )] . Carbonic Anhydrase Inhibitors Clinical Impact Concomitant use of topiramate with any other carbonic anhydrase inhibitor may increase the severity of metabolic acidosis and may also increase the ri …

8 USE IN SPECIFIC POPULATIONS Lactation : Breastfeeding not recommended ( 8.2 ). 8.1 Pregnancy Risk Summary Phentermine and topiramate extended-release capsules are contraindicated in pregnant patients. The use of phentermine and topiramate extended-release capsules can cause fetal harm, and weight loss offers no clear clinical benefit to a pregnant patient (see Clinical Considerations ) . Available data from pregnancy registries and epidemiologic studies indicate an increased risk of major congenital malformations, including but not limited to cleft lip and/or cleft palate (oral clefts), and of being SGA in infants exposed in utero to topiramate (see Data ) . When phentermine and topiramate were co-administered to rats at doses of 3.75 and 25 mg/kg, respectively [approximately 2 times the maximum recommended human dose (MRHD) based on area under the curve (AUC)], or at the same dose to rabbits (approximately 0.1 times and 1 time, respectively, the clinical exposures at the MRHD based on AUC), there were no drug-related malformations. However, structural malformations, including craniofacial defects and reduced fetal weights occurred in offspring of multiple species of pregnant animals administered topiramate at clinically relevant doses (see Data ) . Advise pregnant women of the potential risk to a fetus. Clinical Considerations Disease Associated Maternal and/or Embryo/Fetal Risk Weight loss during pregnancy may result in fetal harm. Appropriate weight gain based on pre-pregnancy weight is currently recommended for all pregnant patients, including those who are already overweight or obese, due to the obligatory weight gain that occurs in maternal tissues during pregnancy. Maternal obesity increases the risk for congenital malformations, including neural tube defects, cardiac malformations, oral clefts, and limb reduction defects. Fetal/Neonatal Adverse Reactions Phentermine and topiramate extended-release capsules can cause metabolic acidosis [see Warnings and Precautions (5.7) ] . The effect of topiramate-induced metabolic acidosis has not been studied in pregnancy; however, metabolic acidosis in pregnancy (due to other causes) can cause decreased fetal growth, decreased fetal oxygenation, and fetal death, and may affect the fetus' ability to tolerate labor. Data Human Data Data evaluating the risk of major congenital malformations, oral clefts, and being SGA with topiramate exposure during pregnancy is available from the North American Antiepileptic Drug (NAAED) Pregnancy Registry and from several larger retrospective epidemiologic studies. Major Congenital Malformations The NAAED Pregnancy Registry indicates an increased risk of major congenital malformations, including but not limited to oral clefts in infants exposed to topiramate during the first trimester of pregnancy. Other than oral clefts, no specific pattern of major congenital malformations or grouping of major congenital malformation types were observed. In the NAAED pregnancy registry, when topiramate-exposed infants with only oral clefts were excluded, the prevalence of major congenital malformations (4.1%) was higher than that in infants exposed to a reference antiepileptic drug (AED) (1.8%) or in infants with mothers without epilepsy and without exposure to AEDs (1.1%). Oral Clefts In the NAAED Pregnancy Registry, the prevalence of oral clefts among topiramate-exposed infants (1.4%) was higher than the prevalence in infants exposed to a reference AED (0.3%) or the prevalence in infants with mothers without epilepsy and without exposure to AEDs (0.11%). It was also higher than the background prevalence in United States (0.17%) as estimated by the Centers for Disease Control and Prevention (CDC). The relative risk of oral clefts in topiramate-exposed pregnancies in the NAAED Pregnancy Registry was 12.5 (95% Confidence Interval [CI] 5.9-26.37) as compared to the risk in a background population of untreated women. The UK Epilepsy and Pregnancy Register reported …

12.1 Mechanism of Action Phentermine is a sympathomimetic amine with pharmacologic activity similar to the prototype drugs of this class used in obesity, amphetamine (d- and d/l-amphetamine). Drugs of this class used in obesity are commonly known as "anorectics" or "anorexigenics." The effect of phentermine on weight reduction and long-term maintenance of body weight is likely mediated by release of catecholamines in the hypothalamus, resulting in reduced appetite and decreased food consumption, but other metabolic effects may also be involved. The exact mechanism of action is not known. The precise mechanism of action of topiramate on weight reduction and long-term maintenance of body weight is not known. Topiramate's effect on weight reduction and long-term maintenance of body weight may be due to its effects on both appetite suppression and satiety enhancement, induced by a combination of pharmacologic effects including augmenting the activity of the neurotransmitter gamma-aminobutyrate, modulation of voltage-gated ion channels, inhibition of AMPA/kainite excitatory glutamate receptors, or inhibition of carbonic anhydrase.

11 DESCRIPTION Phentermine and topiramate extended-release capsules are comprised of immediate-release phentermine hydrochloride (expressed as the weight of the free base) and extended-release topiramate. Phentermine and topiramate extended-release capsules contain phentermine hydrochloride USP, a sympathomimetic amine anorectic, and topiramate USP, a sulfamate-substituted monosaccharide. Phentermine Hydrochloride, USP The chemical name of phentermine hydrochloride, USP is α,α-dimethylphenethylamine hydrochloride. The molecular formula is C 10 H 15 N • HCl and its molecular weight is 185.7 (hydrochloride salt) or 149.2 (free base). Phentermine hydrochloride, USP is a white, odorless, hygroscopic, crystalline powder that is soluble in water, methanol, and ethanol. Its structural formula is: Topiramate, USP Topiramate, USP is 2,3:4,5-di-O-isopropylidene-β-D-fructopyranose sulfamate. The molecular formula is C 12 H 21 NO 8 S and its molecular weight is 339.4. Topiramate, USP is a white to off-white crystalline powder with a bitter taste. It is freely soluble in methanol and acetone, sparingly soluble in pH 9 to pH 12 aqueous solutions and slightly soluble in pH 1 to pH 8 aqueous solutions. Its structural formula is: Phentermine and topiramate extended-release capsules are for oral administration and available in four dosage strengths: 3.75 mg/23 mg (phentermine 3.75 mg and topiramate 23 mg extended-release) (equivalent to 4.67 mg of phentermine hydrochloride, USP). 7.5 mg/46 mg (phentermine 7.5 mg and topiramate 46 mg extended-release) (equivalent to 9.33 mg of phentermine hydrochloride, USP). 11.25 mg/69 mg (phentermine 11.25 mg and topiramate 69 mg extended-release) (equivalent to 14.0 mg of phentermine hydrochloride, USP). 15 mg/92 mg (phentermine 15 mg and topiramate 92 mg extended-release) (equivalent to 18.66 mg of phentermine hydrochloride, USP). Each capsule contains the following inactive ingredients: colloidal silicon dioxide, copovidone, ethylcellulose, gelatin, hypromellose, microcrystalline cellulose, polysorbate 80, povidone K-30, sugar spheres (which contain sucrose and corn starch), talc, and titanium dioxide. The 3.75 mg/23 mg strength also contains iron oxide red and iron oxide yellow. The 7.5 mg/46 mg strength also contains FD&C Blue #2 and iron oxide yellow. The 11.25 mg/69 mg strength also contains iron oxide yellow. The 15 mg/92 mg strength also contains iron oxide red. The imprinting ink contains ammonium hydroxide, iron oxide black, propylene glycol, and shellac glaze. 1 1

10 OVERDOSAGE In the event of a significant overdose with phentermine and topiramate extended-release capsules, if the ingestion is recent, the stomach should be emptied immediately by gastric lavage or by induction of emesis. Appropriate supportive treatment should be provided according to the patient's clinical signs and symptoms. In the event of an overdose of phentermine and topiramate extended-release capsules, consider contacting the Poison Help line (1-800-222-1222) or a medical toxicologist for additional overdosage management recommendations. Acute overdose of phentermine may be associated with restlessness, tremor, hyperreflexia, rapid respiration, confusion, aggressiveness, hallucinations, and panic states. Fatigue and depression usually follow the central stimulation. Cardiovascular effects include arrhythmia, hypertension or hypotension, and circulatory collapse. Gastrointestinal symptoms include nausea, vomiting, diarrhea, and abdominal cramps. Fatal poisoning usually terminates in convulsions and coma. Manifestations of chronic intoxication with anorectic drugs include severe dermatoses, marked insomnia, irritability, hyperactivity, and personality changes. A severe manifestation of chronic intoxication is psychosis, often clinically indistinguishable from schizophrenia. Management of acute phentermine intoxication is largely symptomatic and includes lavage and sedation with a barbiturate. Acidification of the urine increases phentermine excretion. Intravenous phentolamine has been suggested for possible acute, severe hypertension, if this complicates phentermine overdosage. Topiramate overdose has resulted in severe metabolic acidosis. Other signs and symptoms include convulsions, drowsiness, speech disturbance, blurred vision, diplopia, impaired mentation, lethargy, abnormal coordination, stupor, hypotension, abdominal pain, agitation, dizziness, and depression. The clinical consequences were not severe in most cases, but deaths have been reported after overdoses involving topiramate. A patient who ingested a dose between 96 and 110 gm topiramate was admitted to hospital with coma lasting 20 to 24 hours followed by full recovery after 3 to 4 days. Hemodialysis is an effective means of removing topiramate from the body.

16 HOW SUPPLIED/STORAGE AND HANDLING Phentermine and topiramate extended-release capsules are available as follows (see Table 15): Table 15. Phentermine and Topiramate Extended-Release Capsules Presentations Strength (phentermine mg/topiramate mg) Description How Supplied NDC # 3.75 mg/23 mg extended-release capsules White opaque cap printed with WPI, orange opaque body printed with 2196 Unit of Use Bottle (30 capsules) 0480-3297-56 7.5 mg/46 mg extended-release capsules White opaque cap printed with WPI, green opaque body printed with 2195 Unit of Use Bottle (30 capsules) 0480-3296-56 11.25 mg/69 mg extended-release capsules Light yellow opaque cap printed with WPI, white opaque body printed with 2299 Unit of Use Bottle (30 capsules) 0480-2299-56 15 mg/92 mg extended-release capsules White opaque cap printed with WPI, dark scarlet opaque body printed with 2194 Unit of Use Bottle (30 capsules) 0480-3295-56 Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Keep container tightly closed and protect from moisture. Keep out of reach of children.