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Important: This site presents data from the FDA Adverse Event Reporting System (FAERS). A report does not mean the drug caused the event. Full disclaimer.

MACITENTAN: 45,325 Adverse Event Reports & Safety Profile

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45,325
Total FAERS Reports
9,886 (21.8%)
Deaths Reported
24,183
Hospitalizations
45,325
As Primary/Secondary Suspect
738
Life-Threatening
582
Disabilities
Apr 18, 2023
FDA Approved
Actelion Pharmaceuticals US...
Manufacturer
Prescription
Status
Yes
Generic Available

Drug Class: Endothelin Receptor Antagonist [EPC] · Route: ORAL · Manufacturer: Actelion Pharmaceuticals US, Inc. · FDA Application: 204410 · HUMAN PRESCRIPTION DRUG · FDA Label: Available

Patent Expires: Sep 11, 2026 · First Report: 10220919 · Latest Report: 20250915

What Are the Most Common MACITENTAN Side Effects?

#1 Most Reported
Dyspnoea
8,315 reports (18.3%)
#2 Most Reported
Death
5,864 reports (12.9%)
#3 Most Reported
Headache
4,856 reports (10.7%)

All MACITENTAN Side Effects by Frequency

Side Effect Reports % of Total Deaths Hosp.
Dyspnoea 8,315 18.4% 1,685 5,903
Death 5,864 12.9% 5,789 2,120
Headache 4,856 10.7% 575 2,694
Diarrhoea 3,669 8.1% 574 2,268
Pneumonia 3,531 7.8% 810 3,162
Nausea 3,463 7.6% 456 2,116
Hospitalisation 3,414 7.5% 500 3,372
Fatigue 3,172 7.0% 485 1,899
Fluid retention 2,861 6.3% 575 2,150
Dizziness 2,704 6.0% 337 1,673
Malaise 2,521 5.6% 431 1,590
Pulmonary arterial hypertension 2,390 5.3% 1,204 1,695
Hypotension 2,318 5.1% 519 1,691
Cough 2,294 5.1% 314 1,404
Condition aggravated 2,198 4.9% 638 1,538
Oedema peripheral 1,932 4.3% 417 1,324
Peripheral swelling 1,921 4.2% 307 1,191
Vomiting 1,900 4.2% 253 1,320
Pain 1,770 3.9% 221 1,093
Chest pain 1,685 3.7% 239 1,277

Who Reports MACITENTAN Side Effects? Age & Gender Data

Gender: 74.3% female, 25.7% male. Average age: 61.5 years. Most reports from: US. View detailed demographics →

Is MACITENTAN Getting Safer? Reports by Year

YearReportsDeathsHosp.
2000 1 0 1
2004 1 0 1
2008 2 0 1
2009 4 1 1
2010 5 2 4
2011 6 2 5
2012 23 9 20
2013 51 11 35
2014 1,206 301 737
2015 1,832 628 1,010
2016 2,613 986 1,514
2017 3,033 1,078 1,950
2018 3,821 1,219 2,560
2019 3,580 1,054 2,355
2020 2,354 558 1,437
2021 1,434 143 835
2022 1,718 201 863
2023 1,424 142 760
2024 965 109 494
2025 333 32 166

View full timeline →

What Is MACITENTAN Used For?

IndicationReports
Pulmonary arterial hypertension 29,246
Product used for unknown indication 9,498
Pulmonary hypertension 5,228
Cor pulmonale chronic 254
Portopulmonary hypertension 153
Connective tissue disorder 107
Systemic scleroderma 74
Pulmonary embolism 68
Heart disease congenital 56
Heritable pulmonary arterial hypertension 43

MACITENTAN vs Alternatives: Which Is Safer?

MACITENTAN vs MACITENTAN\TADALAFIL MACITENTAN vs MAGNESIUM MACITENTAN vs MAGNESIUM ASPARTATE MACITENTAN vs MAGNESIUM ASPARTATE\POTASSIUM ASPARTATE MACITENTAN vs MAGNESIUM HYDROXIDE MACITENTAN vs MAGNESIUM OROTATE MACITENTAN vs MAGNESIUM SALICYLATE MACITENTAN vs MAGNESIUM\MAGNESIUM HEPTAHYDRATE MACITENTAN vs MAGNESIUM\POTASSIUM\SODIUM MACITENTAN vs MAGNESIUM\PYRIDOXINE

Other Drugs in Same Class: Endothelin Receptor Antagonist [EPC]

Official FDA Label for MACITENTAN

Official prescribing information from the FDA-approved drug label.

Drug Description

OPSYNVI ® is a single tablet combination containing two oral components used to treat pulmonary arterial hypertension: macitentan, an endothelin receptor antagonist (ERA), and tadalafil, a phosphodiesterase 5 (PDE5) inhibitor.

Macitentan

Macitentan is an endothelin receptor antagonist. The chemical name of macitentan is N-[5-(4-Bromophenyl)-6-[2-[(5-bromo-2-pyrimidinyl)oxy]ethoxy]-4- pyrimidinyl]-N'-propylsulfamide. It has a molecular formula of C 19 H 20 Br 2 N 6 O 4 S and a molecular weight of 588.27. Macitentan is achiral and has the following structural formula: Macitentan is a crystalline powder that is insoluble in water. In the solid state macitentan is very stable, is not hygroscopic, and is not light sensitive.

Chemical Structure Tadalafil

Tadalafil, an oral treatment for pulmonary arterial hypertension, is a selective inhibitor of cyclic guanosine monophosphate (cGMP)–specific phosphodiesterase type 5 (PDE5). Tadalafil has the empirical formula C 22 H 19 N 3 O 4 representing a molecular weight of 389.41. The structural formula is: The chemical designation is pyrazino[1´,2´:1,6]pyrido[3,4–b]indole-1,4-dione, 6-(1,3- benzodioxol-5-yl)-2,3,6,7,12,12a-hexahydro-2-methyl-, (6R,12aR)-. It is a crystalline solid that is practically insoluble in water and very slightly soluble in ethanol.

Chemical

Structure OPSYNVI OPSYNVI is available as 10 mg/20 mg macitentan/tadalafil and 10 mg/40 mg macitentan/tadalafil film-coated tablets for oral administration. Each OPSYNVI core tablet contains the following inactive ingredients: Hydroxypropyl cellulose, hydroxypropyl cellulose (low-substituted), lactose monohydrate, magnesium stearate, microcrystalline cellulose, polysorbate 80, povidone, sodium starch glycolate, sodium lauryl sulfate. OPSYNVI 10 mg/20 mg tablets are film-coated with a coating material containing hydroxypropyl methylcellulose, iron oxide red, iron oxide yellow, lactose monohydrate, talc, titanium dioxide, and triacetin. OPSYNVI 10 mg/40 mg tablets are film-coated with a coating material containing hydroxypropyl methylcellulose, lactose monohydrate, talc, titanium dioxide, and triacetin.

FDA Approved Uses (Indications)

AND USAGE OPSUMIT is an endothelin receptor antagonist (ERA) indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) in adults to reduce the risks of disease progression and hospitalization for PAH ( 1.1 ).

1.1 Pulmonary Arterial Hypertension OPSUMIT is an endothelin receptor antagonist (ERA) indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) in adults to reduce the risks of disease progression and hospitalization for PAH. Effectiveness was established in a long-term study in PAH patients with predominantly WHO Functional Class II–III symptoms treated for an average of 2 years. Patients had idiopathic and heritable PAH (57%), PAH caused by connective tissue disorders (31%), and PAH caused by congenital heart disease with repaired shunts (8%) <span class="opacity-50 text-xs">[see Clinical Studies (14.1) ]</span> .

Dosage & Administration

AND ADMINISTRATION One 10 mg/20 mg or 10 mg/40 mg tablet taken orally once daily with or without food. ( 2.1 )

2.1 Recommended Dosage OPSYNVI is taken orally once daily with or without food. Swallow the tablets whole, with water. Do not cut, crush, or chew tablets. If the patient misses a dose of OPSYNVI, tell the patient to take it as soon as possible and then take the next dose at the regularly scheduled time. Tell the patient not to take two doses at the same time if a dose has been missed. For patients who are treatment-naïve to any PAH specific therapy or transitioning from ERA monotherapy The recommended starting dose of OPSYNVI is one 10 mg/20 mg tablet taken orally once daily with or without food for one week. If tolerated, up titrate OPSYNVI to one 10 mg/40 mg tablet taken orally once daily with or without food as the maintenance dose. For patients transitioning from PDE5 inhibitor monotherapy or PDE5 inhibitor and ERA therapy in combination The recommended dose of OPSYNVI is one 10 mg/40 mg tablet taken orally once daily.

2.2 Pregnancy Testing in Females of Reproductive Potential Exclude pregnancy before initiating treatment with OPSYNVI in females of reproductive potential <span class="opacity-50 text-xs">[see Boxed Warning , Contraindications (4.1) , Warnings and Precautions (5.1) , and Use in Specific Populations (8.3) ]</span>.

Contraindications

Pregnancy ( 4.1 ) Hypersensitivity ( 4.2 )

Concomitant Organic

Nitrates ( 4.3 )

Concomitant Guanylate

Cyclase (GC) Stimulators ( 4.4 )

4.1 Pregnancy OPSYNVI may cause fetal harm when administered to a pregnant woman. OPSYNVI is contraindicated in females who are pregnant. Macitentan was consistently shown to have teratogenic effects when administered to animals. If OPSYNVI is used during pregnancy, advise the patient of the potential risk to a fetus <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) and Use in Specific Populations (8.1) ]</span> .

4.2 Hypersensitivity OPSYNVI is contraindicated in patients with a history of a hypersensitivity reaction to macitentan, tadalafil, or any component of the product. Hypersensitivity reactions have been reported. Stevens-Johnson syndrome and exfoliative dermatitis have been reported with tadalafil <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) ]</span>.

4.3 Concomitant Organic Nitrates OPSYNVI is contraindicated in patients who are using any form of organic nitrate, either regularly or intermittently. Do not use nitrates within 48 hours of the last dose of OPSYNVI. Tadalafil potentiates the hypotensive effect of nitrates. This potentiation is thought to result from the combined effects of nitrates and tadalafil on the nitric oxide/cGMP pathway <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span>.

4.4 Concomitant Guanylate Cyclase (GC)

Stimulators

Coadministration of GC stimulators such as riociguat with OPSYNVI is contraindicated. Tadalafil may potentiate the hypotensive effects of GC stimulators.

Known Adverse Reactions

REACTIONS Clinically significant adverse reactions that appear in other sections of the labeling include: Hypersensitivity [see Contraindications (4.2) ] Embryo-fetal Toxicity [see Warnings and Precautions (5.1) ] Hepatotoxicity [see Warnings and Precautions (5.2) ] Hypotension [see Warnings and Precautions (5.3) ] Decrease in Hemoglobin [see Warnings and Precautions (5.4) ]

Visual

Loss [see Warnings and Precautions (5.6) and Patient Counseling Information (17) ] Hearing loss [see Warnings and Precautions (5.7) ]

Fluid

Retention [see Warnings and Precautions (5.8) ]

Prolonged

Erection [see Warnings and Precautions (5.11) ] Most common adverse reactions (≥10%) are edema/fluid retention, anemia, and headache/migraine. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Janssen at 1-800-526-7736 (1-800-JANSSEN) 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 trials of another drug and may not reflect the rates observed in practice. The overall safety profile of OPSYNVI is based on data from a double-blind, active-controlled, phase 3 clinical study (A DUE) and an open-label extension study, in patients with PAH <span class="opacity-50 text-xs">[see Clinical Studies (14) ]</span> . In the double-blind portion of the study, a total of 107 patients were treated with OPSYNVI 10 mg/40 mg, 35 patients were treated with 10 mg macitentan monotherapy, and 44 patients were treated with 40 mg tadalafil monotherapy. The duration of exposure to OPSYNVI during the double-blind portion was 16 weeks. The most common adverse reactions (occurring in ≥ 10% of the OPSYNVI-treated patients) from the double-blind study data were edema/fluid retention (21%), anemia (19%), and headache/migraine (18%). The incidence of treatment discontinuations due to adverse events among patients receiving OPSYNVI in the double-blind phase of the study was 8%. The most frequent adverse reactions leading to discontinuation were anemia and hemoglobin decreased (2% grouped) and peripheral edema and peripheral swelling (2% grouped).

Table

3 presents adverse reactions seen in patients treated for 16 weeks during the double-blind portion of A DUE.

Table

3: Adverse Reactions Occurring in 3% or More of Patients Treated with OPSYNVI During the 16-week Double-blind Study Portion of A DUE Adverse Reaction OPSYNVI N=107 % Macitentan Monotherapy N=35 % Tadalafil Monotherapy N=44 % Edema/fluid retention 21 14 16 Anemia 19 3 2 Headache 18 17 14 Abdominal pain 7 3 14 Hypotension 7 0 0 Myalgia 6 0 5 Nasopharyngitis 6 3 0 Nausea 6 0 7 Increased uterine bleeding 5 0 0 Back pain 5 3 9 Flushing 4 6 0 Vomiting 4 0 5 Palpitations 4 3 5 Pain in extremity 3 0 7 Epistaxis 3 0 0 One-hundred eighty-five patients received OPSYNVI in the double-blind or open-label phase of the study. The median exposure to OPSYNVI during the combined double-blind/open-label extension was 59.9 weeks with a mean exposure of 63.2 weeks. Adverse reactions from the combined double-blind/open-label study data were similar to those observed in the double-blind study. The following adverse reactions have been reported during clinical trials with the individual components of OPSYNVI but were not observed in 3% or more of subjects treated with OPSYNVI in the A DUE clinical trial: Macitentan: bronchitis, pharyngitis, transaminases increased, influenza, urinary tract infection. Tadalafil: lower respiratory tract infection, prolonged erections, gastroesophageal reflux disease, vision blurred, tinnitus, swelling face, chest pain.

6.2 Postmarketing Experience Additional adverse reactions have been identified during post-approval use of tadalafil. Because these reactions are reported voluntarily from a population of uncertain size, it is generally not possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Macitentan: liver injury, symptomatic hypotension, hypersensitivity reactions (angioedema, pruritus, and rash). Tadalafil: Cardiovascular and cerebrovascular events including myocardial infarction, sudden cardiac death, stroke, and tachycardia; Nervous system events including, seizure, transient amnesia; Hypersensitivity reactions including urticaria, Stevens-Johnson syndrome, and exfoliative dermatitis; visual field defect, NAION, retinal vascular occlusion; sudden hearing loss, priapism.

FDA Boxed Warning

BLACK BOX WARNING

WARNING: EMBRYO-FETAL TOXICITY OPSYNVI is contraindicated for use during pregnancy because it may cause fetal harm based on animal data [see Contraindications (4.1) , Warnings and Precautions (5.1) , Use in Specific Populations (8.1) ]. Therefore, for females of reproductive potential, exclude pregnancy before the start of treatment with OPSYNVI. Advise use of effective contraception before the initiation of treatment, during treatment, and for one month after stopping treatment with OPSYNVI [see Dosage and Administration (2.2) , Use in Specific Populations (8.3) ]. When pregnancy is detected, discontinue OPSYNVI as soon as possible [see Warnings and Precautions (5.1) ] . WARNING: EMBRYO-FETAL TOXICITY See full prescribing information for complete boxed warning. Based on animal data, OPSYNVI may cause fetal harm if used during pregnancy ( 4.1 , 5.1 , 8.1 ). Females of reproductive potential: exclude pregnancy before start of treatment. Prevent pregnancy prior to initiation of treatment, during treatment and for one month after treatment by using effective methods of contraception ( 2.2 , 8.3 ). When pregnancy is detected, discontinue OPSYNVI as soon as possible ( 5.1 ).

Warnings

AND PRECAUTIONS Hepatotoxicity: ERAs cause hepatotoxicity and liver failure. Obtain baseline liver enzymes and monitor as clinically indicated. ( 5.2 ) Hypotension: Vasodilatory effects may cause hypotension in susceptible patients. ( 5.3 ) Hemoglobin decrease. ( 5.4 )

Worsening Pulmonary

Veno-Occlusive Disease: If pulmonary edema is confirmed, discontinue treatment. ( 5.5 )

Visual

Loss: Sudden loss of vision could be a sign of non-arteritic ischemic optic neuropathy (NAION) and may be permanent. ( 5.6 )

Hearing

Impairment: Cases of sudden decrease or loss of hearing have been reported in patients taking tadalafil. ( 5.7 )

Fluid

Retention: Fluid retention may require intervention. ( 5.8 ) Combination with Other PDE5 Inhibitors: Avoid use with other PDE5 inhibitors. ( 5.9 )

Decreased Sperm

Count: Decreases in sperm count have been observed in patients taking ERAs. ( 5.10 )

Prolonged

Erection: Advise patients to seek emergency treatment if an erection lasts greater than 4 hours. ( 5.11 )

5.1 Embryo-fetal Toxicity Based on data from animal reproduction studies, OPSYNVI may cause fetal harm when administered to a pregnant patient and is contraindicated during pregnancy. The available human data for ERAs do not establish the presence or absence of major birth defects related to the use of OPSYNVI. Advise patients who can become pregnant of the potential risk to a fetus. Obtain a pregnancy test prior to initiation of therapy with OPSYNVI. Advise patients who can become pregnant to use effective contraceptive methods prior to initiation of treatment, during treatment, and for one month after discontinuation of treatment with OPSYNVI. When pregnancy is detected, discontinue use as soon as possible <span class="opacity-50 text-xs">[see Dosage and Administration (2.2) , Contraindications (4.1) , and Use in Specific Populations (8.1 , 8.3) ]</span>.

5.2 Hepatotoxicity ERAs have caused elevations of aminotransferases, hepatotoxicity, and liver failure. The incidence of elevated aminotransferases in the double-blind and combined double-blind (DB)/open-label (OL) arms of the study of OPSYNVI in PAH are shown in Table 1.

Table

1: Incidence of Elevated Aminotransferases in the A DUE Study OPSYNVI DB (N=107) OPSYNVI DB/OL (N=185) ≥3 × ULN 1.0% 3.4% ≥8 × ULN 1.0% 1.1% The overall incidence of treatment discontinuations for hepatic adverse events in the double-blind and combined double-blind/open-label arms study of OPSYNVI in PAH data were 0.9% and 2.2% respectively. The incidence of elevated aminotransferases in the study of OPSUMIT (macitentan) in PAH is shown in Table 2.

Table

2: Incidence of Elevated Aminotransferases in the SERAPHIN Study OPSUMIT 10 mg (N=242) Placebo (N=249) >3 × ULN 3.4% 4.5% >8 × ULN 2.1% 0.4% In the placebo-controlled study of OPSUMIT, discontinuations for hepatic adverse events were 3.3% in the OPSUMIT 10 mg group vs. 1.6% for placebo. Obtain liver enzyme tests prior to initiation of OPSYNVI and repeat during treatment as clinically indicated. Advise patients to report symptoms suggesting hepatic injury (nausea, vomiting, right upper quadrant pain, fatigue, anorexia, jaundice, dark urine, fever, or itching). If clinically relevant aminotransferase elevations occur, or if elevations are accompanied by an increase in bilirubin >2 × ULN, or by clinical symptoms of hepatotoxicity, discontinue OPSYNVI. Consider re-initiation of OPSYNVI when hepatic enzyme levels normalize in patients who have not experienced clinical symptoms of hepatotoxicity. Do not initiate OPSYNVI in patients with elevated aminotransferases (> 3 × upper limit of normal [ULN]) at baseline. Patients with severe hepatic cirrhosis (Child-Pugh Class C) have not been studied, and, therefore, avoid use of OPSYNVI.

5.3 Hypotension OPSYNVI tablets have vasodilatory properties that may result in transient decreases in blood pressure. Prior to prescribing OPSYNVI tablets, carefully consider whether patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects. Patients with pre-existing hypotension, with autonomic dysfunction, with left ventricular outflow obstruction, may be particularly sensitive to the actions of vasodilators <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span>.

5.4 Hemoglobin Decrease Decreases in hemoglobin concentration and hematocrit have occurred following administration of other ERAs and were observed in clinical studies with OPSYNVI and OPSUMIT. These decreases occurred early and stabilized thereafter. In the placebo-controlled study of OPSUMIT in PAH, OPSUMIT 10 mg caused a mean decrease in hemoglobin from baseline to up to 18 months of about 1.0 g/dL compared to no change in the placebo group. A decrease in hemoglobin to below 10.0 g/dL was reported in 8.7% of the OPSUMIT 10 mg group and in 3.4% of the placebo group. Similar results were observed in the trial with OPSYNVI. Decreases in hemoglobin seldom require transfusion. Initiation of OPSYNVI is not recommended in patients with severe anemia. Measure hemoglobin prior to initiation of treatment and repeat during treatment as clinically indicated <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span>.

5.5 Worsening Pulmonary Veno-Occlusive Disease (PVOD) Pulmonary vasodilators may significantly worsen the cardiovascular status of patients with pulmonary veno-occlusive disease (PVOD). Since there are no clinical data on administration of OPSYNVI tablets to patients with veno-occlusive disease, administration of OPSYNVI tablets to such patients is not recommended. Should signs of pulmonary edema occur when OPSYNVI tablets are administered, the possibility of associated PVOD should be considered. If confirmed, discontinue OPSYNVI.

5.6 Visual Loss Non–arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision, including permanent loss of vision, has been reported postmarketing in temporal association with the use of PDE5 inhibitors, including tadalafil. Most, but not all, of these patients had underlying anatomic or vascular risk factors for development of NAION, including: low cup to disc ratio (&quot;crowded disc&quot;), age over 50, diabetes, hypertension, coronary artery disease, hyperlipidemia, and smoking. Based on published literature, the annual incidence of NAION is 2.5–11.8 cases per 100,000 in males aged greater than or equal to 50 in the general population. Other risk factors for NAION, such as the presence of &quot;crowded&quot; optic disc, may have contributed to the occurrence of NAION. Patients with known hereditary degenerative retinal disorders, including retinitis pigmentosa, were not included in the clinical trials, and use of OPSYNVI in these patients is not recommended.

5.7 Hearing Impairment Cases of sudden decrease or loss of hearing, which may be accompanied by tinnitus and dizziness, have been reported in patients taking tadalafil. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors.

5.8 Fluid Retention Peripheral edema and fluid retention are known clinical consequences of PAH and known effects of ERAs and heart failure has been reported in patients taking OPSYNVI. In the active-controlled and combined double-blind/open-label arms of the study of OPSYNVI in PAH, the incidence of peripheral edema/fluid retention was 20.6% in the active-controlled and 17.3% in the double-blind/open-label arm <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . In the placebo-controlled study of OPSUMIT in PAH, the incidence of edema was 21.9% in the OPSUMIT 10 mg group and 20.5% in the placebo group. Patients with underlying left ventricular dysfunction may be at particular risk for developing significant fluid retention after initiation of ERA treatment. In a small study of OPSUMIT in patients with pulmonary hypertension because of left ventricular dysfunction, more patients in the OPSUMIT group developed significant fluid retention and had more hospitalizations because of worsening heart failure compared to those randomized to placebo. Postmarketing cases of edema and fluid retention occurring within weeks of starting OPSUMIT, some requiring intervention with a diuretic or hospitalization for decompensated heart failure, have been reported . Monitor for signs of fluid retention after OPSYNVI initiation. If clinically significant fluid retention develops, evaluate the patient to determine the cause, such as OPSYNVI or underlying heart failure, and the possible need to discontinue OPSYNVI.

5.9 Combination with Other PDE5 Inhibitors Tadalafil is also indicated for erectile dysfunction. The safety and efficacy of taking tadalafil tablets together with another PDE5 inhibitors or other treatments for erectile dysfunction have not been studied. Instruct patients taking OPSYNVI tablets not to take other PDE5 inhibitors.

5.10 Decreased Sperm Count Macitentan, like other ERAs, may have an adverse effect on spermatogenesis. Counsel men about potential effects on fertility <span class="opacity-50 text-xs">[see Use in Specific Populations (8.3) and Nonclinical Toxicology (13.1) ]</span>.

5.11 Prolonged Erection There have been reports of prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) for PDE5 inhibitors like tadalafil. Patients with conditions that might predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia), or in patients with anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie&apos;s disease) are at an increased risk. Priapism, if not treated promptly, can result in irreversible damage to the erectile tissue. Patients who have an erection lasting greater than 4 hours, whether painful or not, should seek emergency medical attention.

Drug Interactions

INTERACTIONS Strong CYP3A4 Inducers/Inhibitors: Avoid concomitant use ( 7.2 , 7.3 )

Moderate

Dual or Combined CYP3A4 and CYP2C9 Inhibitors: Avoid concomitant use ( 7.4 )

7.1 Nitrates Administration of nitrates within 48 hours after the last dose of OPSYNVI is contraindicated <span class="opacity-50 text-xs">[see Contraindications (4.3) ]</span> .

7.2 Strong CYP3A4 Inducers Strong inducers of CYP3A4 such as rifampin significantly reduce macitentan exposure. Use of OPSYNVI with strong CYP3A4 inducers should be avoided <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

7.3 Strong CYP3A4 Inhibitors Concomitant use of strong CYP3A4 inhibitors like ketoconazole increase exposure to both macitentan and tadalafil. Avoid concomitant use of OPSYNVI with strong CYP3A4 inhibitors such as ritonavir, ketoconazole and itraconazole. Use other PAH treatment options when strong CYP3A4 inhibitors are needed <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

7.4 Moderate Dual or Combined CYP3A4 and CYP2C9 Inhibitors Concomitant use of moderate dual inhibitors of CYP3A4 and CYP2C9 such as fluconazole is predicted to increase macitentan exposure approximately 4-fold. Avoid concomitant use of OPSYNVI with moderate dual inhibitors of CYP3A4 and CYP2C9 (such as fluconazole and amiodarone) <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>. Concomitant treatment of both a moderate CYP3A4 inhibitor and moderate CYP2C9 inhibitor with OPSYNVI should also be avoided <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span>.

7.5 Alpha-Blockers PDE5 inhibitors, including tadalafil, and alpha-adrenergic blocking agents are both vasodilators with blood-pressure-lowering effects. In patients who are taking alpha 1 blockers, concomitant administration of tadalafil may lead to symptomatic hypotension in some patients. Therefore, the combination of OPSYNVI and doxazosin is not recommended <span class="opacity-50 text-xs">[see Warnings and Precautions (5.3) and Clinical Pharmacology (12.2) ]</span>.

7.6 Antihypertensives PDE5 inhibitors, including tadalafil, are mild systemic vasodilators. Clinical pharmacology studies were conducted to assess the effect of tadalafil on the potentiation of the blood–pressure–lowering effects of selected antihypertensive medications (amlodipine, angiotensin II receptor blockers, bendroflumethiazide, enalapril, and metoprolol). Small reductions in blood pressure occurred following coadministration of tadalafil with these agents compared with placebo <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span>.

7.7 Alcohol Both alcohol and tadalafil, a PDE5 inhibitor, act as mild vasodilators. When mild vasodilators are taken in combination, blood-pressure–lowering effects of each individual compound may be increased. Substantial consumption of alcohol (e.g., 5 units or greater) in combination with OPSYNVI can increase the potential for orthostatic signs and symptoms, including increase in heart rate, decrease in standing blood pressure, dizziness, and headache. Tadalafil (10 mg or 20 mg) did not affect alcohol plasma concentrations and alcohol did not affect tadalafil plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2) ]</span>.