BELBUCA

Boxed Warning 12/2025 Indications and Usage ( 1 ) 12/2025 Dosage and Administration ( 2.2 , 2.3 , 2.5 ) 12/2025 Warnings and Precautions ( 5.1 , 5.2 , 5.3 , 5.12 , 5.17 ) 12/2025

1 INDICATIONS AND USAGE BELBUCA is indicated for the management of severe and persistent pain that requires an opioid analgesic and that cannot be adequately treated with alternative options, including immediate-release opioids. BELBUCA buccal film contains buprenorphine, a partial opioid agonist. BELBUCA is indicated for the management of severe and persistent pain that requires an opioid analgesic that cannot be adequately treated with alternative options, including immediate-release opioids. ( 1 ) Limitations of Use Because of the risks of addiction, abuse, misuse, overdose, and death, which can occur at any dosage or duration and persist over the course of therapy, reserve opioid analgesics, including BELBUCA, for use in patients for whom alternative treatment are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain. ( 1 , 5.1 ) BELBUCA is not indicated as an as-needed (prn) analgesic. ( 1 ) Limitations of Use Because of the risks of addiction, abuse, misuse, overdose, and death, which can occur at any dosage or duration and persist over the course of therapy [see Warnings and Precautions (5.1) ] , reserve opioid analgesics, including BELBUCA, for use in patients for whom alternative treatment options are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain. BELBUCA is not indicated as an as-needed (prn) analgesic.

2 DOSAGE AND ADMINISTRATION BELBUCA should be prescribed only by healthcare professionals who are knowledgeable about the use of extended-release/long-acting opioids and how to mitigate the associated risks. ( 2.1 ) Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals. Reserve titration to higher doses of BELBUCA for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks ( 2.1 , 5 ) Initiate the dosing regimen for each patient individually, taking into account the patient's underlying cause and severity of pain, prior analgesic treatment and response, and risk factors for addiction, abuse, and misuse. ( 2.1 , 5.1 ) Respiratory depression can occur at any time during opioid therapy, especially when initiating and following dosage increases with BELBUCA. Consider this risk when selecting an initial dose and when making dose adjustments. ( 2.1 , 5.2 ). Discuss opioid overdose reversal agents and options for acquiring them with the patient and/or caregiver, both when initiating and renewing treatment with BELBUCA, especially if the patient has additional risk factors for overdose, or close contacts at risk for exposure and overdose. ( 2.2 , 5.1 , 5.2 , 5.3 ) BELBUCA buccal film is for oral buccal use only and is to be applied to the buccal mucosa once daily or every 12 hours. ( 2.1 ) Patients who are not Opioid Tolerant: Initiate therapy with 75 mcg BELBUCA once daily or every 12 hours, as tolerated, for at least 4 days before increasing dose to 150 mcg every 12 hours. ( 2.3 ) Conversion from Other Opioid Analgesics to BELBUCA : Taper current daily opioid dose to 30 mg oral morphine sulfate equivalents (MSE) or less prior to initiating therapy with BELBUCA. ( 2.3 ) For patients taking less than 30 mg oral MSE, initiate therapy with 75 mcg once daily or every 12 hours. ( 2.3 ) For patients taking between 30 mg and 89 mg oral MSE, initiate therapy with 150 mcg BELBUCA every 12 hours following analgesic taper. ( 2.3 ) For patients taking between 90 mg and 160 mg oral MSE, initiate therapy with 300 mcg BELBUCA every 12 hours following analgesic taper. ( 2.3 ) For patients taking greater than 160 mg oral MSE, consider alternate analgesic. ( 2.3 ) BELBUCA doses of 600 mcg, 750 mcg, and 900 mcg are only for use following titration from lower doses of BELBUCA. ( 2.3 ) Patients with Severe Hepatic Impairment : Reduce the starting and incremental dose by half that of patients with normal liver function. ( 2.6 , 5.19 , 8.6 ) Patients with Oral Mucositis : Reduce the starting and incremental dose by half that of patients without mucositis. ( 2.7 , 5.20 ) Periodically reassess patients receiving BELBUCA to evaluate the continued need for opioid analgesics to maintain pain control, for the signs or symptoms of adverse reactions, and for the development of addiction, abuse, or misuse. ( 2.4 ) Do not rapidly reduce or abruptly discontinue BELBUCA in a physically-dependent patient because rapid reduction or abrupt discontinuation of opioid analgesics has resulted in serious withdrawal symptoms, uncontrolled pain, and suicide. ( 2.5 , 5.17 ) 2.1 Important Dosage and Administration Instructions BELBUCA should be prescribed only by healthcare professionals who are knowledgeable about the use of extended-release/long-acting opioids and how to mitigate the associated risks. Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals [see Warnings and Precautions (5) ]. Because the risk of overdose increases as opioid doses increase, reserve titration to higher doses of BELBUCA for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks. Initiate the dosing regimen for each patient individually, taking into account the patient' …

3 DOSAGE FORMS AND STRENGTHS Dosage strengths of BELBUCA are based on the active moiety, buprenorphine. The 75 mcg dosage form is a buccal film that contains 75 mcg buprenorphine. The film is white on one side, with E0 printed in black, and yellow on the other side. The 150 mcg dosage form is a buccal film that contains 150 mcg buprenorphine. The film is white on one side, with E1 printed in black, and yellow on the other side. The 300 mcg dosage form is a buccal film that contains 300 mcg buprenorphine. The film is white on one side, with E3 printed in black, and yellow on the other side. The 450 mcg dosage form is a buccal film that contains 450 mcg buprenorphine. The film is white on one side, with E4 printed in black, and yellow on the other side. The 600 mcg dosage form is a buccal film that contains 600 mcg buprenorphine. The film is white on one side, with E6 printed in black, and yellow on the other side. The 750 mcg dosage form is a buccal film that contains 750 mcg buprenorphine. The film is white on one side, with E7 printed in black, and yellow on the other side. The 900 mcg dosage form is a buccal film that contains 900 mcg buprenorphine. The film is white on one side, with E9 printed in black, and yellow on the other side. Buccal film available in 75 mcg, 150 mcg, 300 mcg, 450 mcg, 600 mcg, 750 mcg, and 900 mcg dosage strengths. ( 3 )

4 CONTRAINDICATIONS BELBUCA is contraindicated in patients with: Significant respiratory depression [see Warnings and Precautions (5.2) ] Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment [see Warnings and Precautions (5.7) ] Known or suspected gastrointestinal obstruction, including paralytic ileus [see Warnings and Precautions (5.12) ] Hypersensitivity (e.g., anaphylaxis) to buprenorphine [see Warnings and Precautions (5.16) , Adverse Reactions (6) ] Significant respiratory depression ( 4 ) Acute or severe bronchial asthma in an unmonitored setting or in absence of resuscitative equipment ( 4 ) Known or suspected gastrointestinal obstruction, including paralytic ileus ( 4 ) Hypersensitivity to buprenorphine ( 4 )

6 ADVERSE REACTIONS The following serious adverse reactions described elsewhere in the labeling include: Addiction, Abuse, and Misuse [see Warnings and Precautions (5.1) ] Life-Threatening Respiratory Depression [see Warnings and Precautions (5.2) ] Interactions with Benzodiazepines and Other CNS Depressants [see Warnings and Precautions (5.3) ] Neonatal Opioid Withdrawal Syndrome [see Warnings and Precautions (5.4) ] Opioid-Induced Hyperalgesia and Allodynia [see Warnings and Precautions (5.6) ] Adrenal Insufficiency [see Warnings and Precautions (5.8) ] Severe Hypotension [see Warnings and Precautions (5.9) ] Hepatotoxicity [see Warnings and Precautions (5.11) ] Gastrointestinal Adverse Reactions [see Warnings and Precautions (5.12) ] Seizures [see Warnings and Precautions (5.13) ] QTc Prolongation [see Warnings and Precautions (5.15) ] Anaphylactic/Allergic Reactions [see Warnings and Precautions (5.16) ] Most common adverse reactions (>5%) include nausea, constipation, headache, vomiting, dizziness, and somnolence. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Collegium Pharmaceutical, Inc. at 1-855-331-5615 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial 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 trials of another drug and may not reflect the rates observed in practice. A total of 2,127 patients were treated with BELBUCA in controlled and open-label chronic pain trials. There were 504 patients treated for approximately six months and 253 patients treated for approximately one year. The clinical trial population consisted of patients with chronic moderate-to-severe pain. The most common serious adverse drug reactions (all ≤ 0.2%) occurring during clinical trials with BELBUCA were: cellulitis, pneumonia, ileus, atrial fibrillation, coronary artery disease, cerebrovascular accident, syncope, transient ischemic attack, chest pain, non-cardiac chest pain, ankle fracture, cholecystitis, osteoarthritis, and dehydration. The most common adverse events (≥ 2%) leading to discontinuation were nausea, vomiting, and liver function test abnormality. The most common adverse events (≥ 5%) reported by patients who were not opioid tolerant, opioid-experienced patients, and overall patients exposed to BELBUCA in clinical trials and compared against placebo are shown in Table 2, Table 3 and Table 4: Table 2: Adverse Events Reported in ≥ 5% of Patients during the Open-Label Titration Phase and Double-Blind Treatment Phase of Controlled Studies: Patients Who Were Not Opioid Tolerant Open-Label Titration Phase Double-Blind Treatment Phase MedDRA Preferred Term BELBUCA (N=749) BELBUCA (N=229) Placebo (N=232) Nausea 50% 10% 7% Constipation 13% 4% 3% Vomiting 8% 4% <1% Headache 8% 2% 3% Dizziness 6% 2% <1% Somnolence 7% 1% <1% Fatigue 5% 0% 1% Table 3: Adverse Events Reported in ≥ 5% of Patients during the Open-Label Titration Phase and Double-Blind Treatment Phase of Controlled Studies: Opioid-Experienced Patients Open-Label Titration Phase Double-Blind Treatment Phase MedDRA Preferred Term BELBUCA (N=810) BELBUCA (N=254) Placebo (N=256) Nausea 17% 7% 7% Constipation 8% 3% 1% Vomiting 7% 5% 2% Headache 7% 2% 3% Dizziness 5% 2% <1% Somnolence 5% 1% <1% Drug Withdrawal Syndrome 0% 4% 10% Table 4: Adverse Events Reported in ≥ 5% of Patients during the Open-Label Titration Phase and Double-Blind Treatment Phase of Controlled Studies Open-Label Titration Phase Double-Blind Treatment Phase MedDRA Preferred Term BELBUCA (N=1889) BELBUCA (N=600) Placebo (N=606) Nausea 33% 9% 8% Constipation 11% 4% 2% Vomiting 7% 5% 2% Headache 8% 4% 3% Dizziness 6% 2% <1% Somnolence 6% <1% <1% Drug Withdrawal Syndrome 1% 2% 5% The most common (≥ 5%), common (≥ 1% to < 5%), and least common (< 1%) adverse reactions reported by patients taking BELBUCA in the controlled and open-label clini …

7 DRUG INTERACTIONS Table 5 includes clinically significant drug interactions with BELBUCA. Table 5: Clinically Significant Drug Interactions Benzodiazepines Clinical Impact: There have been a number of reports regarding coma and death associated with the misuse and abuse of the combination of buprenorphine and benzodiazepines. In many, but not all of these cases, buprenorphine was misused by self-injection of crushed buprenorphine tablets. Preclinical studies have shown that the combination of benzodiazepines and buprenorphine altered the usual ceiling effect on buprenorphine-induced respiratory depression, making the respiratory effects of buprenorphine appear similar to those of full opioid agonists. Intervention: Regularly evaluate patients with concurrent use of BELBUCA and benzodiazepines. Warn patients that it is extremely dangerous to self-administer benzodiazepines while taking BELBUCA and warn patients to use benzodiazepines concurrently with BELBUCA only as directed by their physician. Benzodiazepines and Other Central Nervous System (CNS) Depressants Clinical Impact: Due to additive pharmacologic effect, the concomitant use of benzodiazepines or other CNS depressants, including alcohol, can increase the risk of hypotension, respiratory depression, profound sedation, coma, and death [see Warnings and Precautions (5.3) ] . Intervention: Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Inform patients and caregivers of this potential interaction and educate them on the signs and symptoms of respiratory depression (including sedation). If concomitant use is warranted, consider recommending or prescribing an opioid overdose reversal agent [see Dosage and Administration (2.2) , Warnings and Precautions (5.1 , 5.2 , 5.3) ] . Examples: Benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, gabapentinoids (gabapentin or pregabalin),, other opioids, alcohol. Inhibitors of CYP3A4 Clinical Impact: The concomitant use of BELBUCA and CYP3A4 inhibitors can increase the plasma concentration of buprenorphine, resulting in increased or prolonged opioid effects, particularly when an inhibitor is added after a stable dose of BELBUCA is achieved. After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the buprenorphine plasma concentration will decrease [see Clinical Pharmacology (12.3) ] , potentially resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to buprenorphine. Intervention: If concomitant use is necessary, consider dosage reduction of BELBUCA until stable drug effects are achieved. Evaluate patients at frequent intervals for respiratory depression and sedation. If a CYP3A4 inhibitor is discontinued, consider increasing the BELBUCA dosage until stable drug effects are achieved. Assess for signs of opioid withdrawal. Examples: Macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g., ketoconazole), protease inhibitors (e.g., ritonavir) CYP3A4 Inducers Clinical Impact: The concomitant use of BELBUCA and CYP3A4 inducers can decrease the plasma concentration of buprenorphine [see Clinical Pharmacology (12.3) ] , potentially resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to buprenorphine. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the buprenorphine plasma concentration will increase [see Clinical Pharmacology (12.3) ] , which could increase or prolong both therapeutic effects and adverse reactions and may cause serious respiratory depression. Intervention: If concomitant use is necessary, consider increasing the BELBUCA dosage until stable drug effects are achieved. Evaluate patients for signs of opioid withdrawal. If a CYP3A4 inducer is d …

8 USE IN SPECIFIC POPULATIONS Pregnancy : May cause fetal harm. ( 8.1 ) Lactation : Not recommended. ( 8.2 ) Moderate or Severe Hepatic Impairment : Periodically assess for signs and symptoms of toxicity or overdose. ( 5.19 , 8.6 ) 8.1 Pregnancy Risk Summary Use of opioid analgesics for an extended period of time during pregnancy may cause neonatal opioid withdrawal syndrome [see Warnings and Precautions (5.4) ] . There are no adequate and well-controlled studies of BELBUCA or buprenorphine in pregnant women. Limited published data on use of buprenorphine, the active ingredient in BELBUCA, in pregnancy, have not shown an increased risk of major malformations. Reproductive and developmental studies in rats and rabbits identified adverse events at approximately 2 times the maximum recommended human dose (MRHD) of 1.8 mg/day of BELBUCA. Embryofetal death was observed in both rats and rabbits administered buprenorphine during the period of organogenesis at doses approximately 54 and 2.2 times, respectively, the MRHD of 1.8 mg/day of buprenorphine. Pre-and postnatal development studies in rats demonstrated increased neonatal deaths at 2.7 times and above and dystocia at approximately 27 times the MRHD of 1.8 mg/day of buprenorphine. No clear teratogenic effects were seen when buprenorphine was administered during organogenesis with a range of doses 5 times or greater than the MRHD of 1.8 mg/day of buprenorphine. However, increases in skeletal abnormalities were noted in rats and rabbits administered buprenorphine daily during organogenesis at doses approximately 5.4 and 10.8 times the MRHD of 1.8 mg/day of buprenorphine, respectively. In a few studies, some events such as acephalus and omphalocele were also observed but these findings were not clearly treatment-related [see Data ] . The background risk of major birth defects and miscarriage for the indicated population is unknown. Adverse outcomes in pregnancy can occur regardless of the health of the mother or the use of medications. 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. Clinical Considerations Fetal/Neonatal Adverse Reactions Use of opioid analgesics for an extended period of time during pregnancy for medical or nonmedical purposes can result in physical dependence in the neonate and neonatal opioid withdrawal syndrome shortly after birth. Neonatal opioid withdrawal syndrome presents as irritability, hyperactivity and abnormal sleep pattern, high pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. The onset, duration, and severity of neonatal opioid withdrawal syndrome vary based on the specific opioid used, duration of use, timing and amount of last maternal use, and rate of elimination of the drug by the newborn. Observe newborns for symptoms of neonatal opioid withdrawal syndrome and manage accordingly [see Warnings and Precautions (5.4) ] . Labor or Delivery Opioids cross the placenta and may produce respiratory depression and psycho-physiologic effects in neonates. An opioid overdose reversal agent, such as naloxone or nalmefene, must be available for reversal of opioid-induced respiratory depression in the neonate. BELBUCA is not recommended for use in women immediately prior to labor, when shorter-acting analgesics or other analgesic techniques are more appropriate. Opioid analgesics, including BELBUCA, can prolong labor through actions which temporarily reduce the strength, duration, and frequency of uterine contractions. However, this effect is not consistent and may be offset by an increased rate of cervical dilation, which tends to shorten labor. Data Animal Data The exposure margins listed below are based on body surface area comparisons (mg/m 2 ) to MRHD of 1.8 mg buprenorphine via BELBUCA. Following oral administration to rats no teratogenic effects were observed at buprenorphine doses up to 250 mg/kg/day (estim …

12.1 Mechanism of Action Buprenorphine is a partial agonist at the mu-opioid receptor and an antagonist at the kappa-opioid receptor.

11 DESCRIPTION BELBUCA is a buccal film that provides transmucosal delivery of buprenorphine, a partial opioid agonist. BELBUCA is a rectangular bi-layer, peppermint-flavored, buccal film with rounded corners, consisting of a white to off-white backing layer with strength identifier printed in black ink and a light yellow to yellow active mucoadhesive layer containing buprenorphine hydrochloride. The yellow side of the film is applied to the inside of the cheek where it adheres to the moist buccal mucosa to deliver the drug as the film dissolves. Buprenorphine hydrochloride USP is the active ingredient in BELBUCA. The chemical name of buprenorphine hydrochloride is 6,14-ethenomorphinan-7-methanol, 17-(cyclopropylmethyl)- α-(1,1-dimethylethyl)-4, 5-epoxy-18,19-dihydro-3-hydroxy-6-methoxy-α-methyl-, hydrochloride, [5α, 7α, (S)]. Its structural formula is as follows: The molecular weight of buprenorphine hydrochloride is 504.10; the empirical formula is C 29 H 41 NO 4 ∙HCl. Buprenorphine hydrochloride occurs as a white or off-white crystalline powder. It is sparingly soluble in water, freely soluble in methanol, soluble in alcohol, and practically insoluble in cyclohexane. The pKa is 8.5 for the amine function and 10.0 for the phenol function. Dosage strengths of BELBUCA are based on the active moiety, buprenorphine. BELBUCA is available as 75 mcg, 150 mcg, 300 mcg, 450 mcg, 600 mcg, 750 mcg, and 900 mcg buprenorphine per film. The strength of each film is dependent on the buprenorphine concentration in the formulation and the surface area of the film. Table 6 lists the dosage strength, equivalent amount of buprenorphine hydrochloride USP (active ingredient), unique identifier and film size for each strength. Table 6: BELBUCA Identifier and Film Size Buprenorphine Strength (mcg) Buprenorphine Hydrochloride (mcg) BELBUCA Identifier Film Size (cm 2 ) 75 80.9 E0 1.215 150 161.8 E1 2.431 300 323.4 E3 0.934 450 485.1 E4 1.400 600 646.8 E6 1.867 750 808.5 E7 2.334 900 970.2 E9 2.801 Each buccal film also contains carboxymethylcellulose sodium USP, citric acid anhydrous USP, hydroxyethylcellulose NF, hydroxypropylcellulose NF, methylparaben NF, monobasic sodium phosphate anhydrous USP, peppermint oil NF, polycarbophil USP, propylene glycol USP, propylparaben NF, sodium benzoate NF, sodium hydroxide NF, saccharin sodium NF, titanium dioxide USP, vitamin E acetate USP, yellow iron oxide, purified water USP, and TekPrint SW-9008 black ink (shellac NF, black iron oxide NF). Chemical Structure

10 OVERDOSAGE Clinical Presentation Acute overdosage with buprenorphine is manifested by respiratory depression, somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and, in some cases, pulmonary edema, bradycardia, hypotension, hypoglycemia, partial or complete airway obstruction, atypical snoring, and death. Marked mydriasis rather than miosis may be seen due to severe hypoxia in overdose situations [see Clinical Pharmacology (12.2) ] . Toxic leukoencephalopathy has been reported after opioid overdose and can present hours, days, or weeks after apparent recovery from the initial intoxication. Treatment of Overdose In case of overdose, priorities are the re-establishment of a patent and protected airway and institution of assisted or controlled ventilation, if needed. Employ other supportive measures (including oxygen, vasopressors) in the management of circulatory shock and pulmonary edema, as indicated. Cardiac arrest or arrhythmias will require advanced life support measures. Naloxone may not be effective in reversing any respiratory depression produced by buprenorphine. High doses of naloxone, 10-35 mg/70 kg, may be of limited value in the management of buprenorphine overdose. The onset of naloxone effect may be delayed by 30 minutes or more. Because the duration of reversal would be expected to be less than the duration of action of buprenorphine from BELBUCA, carefully monitor the patient until spontaneous respiration is reliably re-established. Even in the face of improvement, continued medical monitoring is required for at least 24 hours because of the possibility of extended effects of buprenorphine. In an individual physically dependent on opioids, administration of an opioid overdose reversal agent may precipitate an acute withdrawal. The severity of the withdrawal symptoms experienced will depend on the degree of physical dependence and the dose of the reversal agent administered. If a decision is made to treat serious respiratory depression in the physically dependent patient, administration of the reversal agent should be initiated with care and by titration with smaller than usual doses of the reversal agent.

16 HOW SUPPLIED/STORAGE AND HANDLING BELBUCA (buprenorphine buccal film) films are supplied in cartons containing 60 individual child-resistant foil packages as follows: Strength NDC Number Carton NDC Number Foil Package Foil Color The 75 mcg buccal film is printed with E0 59385-021-60 59385-021-01 Red The 150 mcg buccal film is printed with E1 59385-022-60 59385-022-01 Green The 300 mcg buccal film is printed with E3 59385-023-60 59385-023-01 Gray The 450 mcg buccal film is printed with E4 59385-024-60 59385-024-01 Purple The 600 mcg buccal film is printed with E6 59385-025-60 59385-025-01 Blue The 750 mcg buccal film is printed with E7 59385-026-60 59385-026-01 Light Blue The 900 mcg buccal film is printed with E9 59385-027-60 59385-027-01 Orange Store at 20°C to 25°C (68°F to 77°F), with excursions permitted between 15°C and 30°C (59°F and 86°F). Store BELBUCA securely and dispose of properly.