With its unique pharmacological effects, Ambrisentan has brought good news to many patients, helping them alleviate the pain caused by diseases. Just like any other medication, the use of Ambrisentan requires extra caution.
Ambrisentan(Endobloc):Clinical Uses, Recommended Dosage, Treatment Effect
This article provides a detailed explanation of Ambrisentan's indications, dosage and administration, side effects, contraindications, clinical efficacy, and other aspects.
(I) Indications
Ambrisentan is indicated for the treatment of pulmonary arterial hypertension (PAH). It can improve exercise capacity and delay clinical deterioration.
(II) Dosage and Administration
1. Medication Administration: Do not split, crush, or chew the tablets.
2. Dosage for Adults: Initiate treatment with 5 mg once daily. Every 4 weeks, the dose of Ambrisentan may be increased to a maximum of 10 mg daily based on the patient's needs and tolerability.
3. Pregnancy Testing for Women of Reproductive Potential: Women of reproductive potential should start taking Ambrisentan tablets only after a negative pregnancy test. Pregnancy tests should be conducted monthly during the treatment period.
(III) Target Population
Adults. Pregnant women, lactating women, children, and elderly patients should use this medication under the guidance of a doctor.
(IV) Contraindications
1. Pregnant Women
Ambrisentan may cause harm to the fetus when administered to pregnant women. Ambrisentan is contraindicated in pregnant women.
2. Idiopathic Pulmonary Fibrosis (IPF)
Ambrisentan is contraindicated in patients with idiopathic pulmonary fibrosis (IPF), including those with IPF complicated by pulmonary arterial hypertension.
(V) Side Effects
The most common adverse reactions (occurring in >3% of patients compared with placebo) are peripheral edema, nasal congestion, sinusitis, and flushing.
(VI) Precautions
1. Embryo-Fetal Toxicity
Ambrisentan may cause harm to the fetus if taken during pregnancy and is contraindicated in pregnant women. For women of reproductive potential, pregnancy must be excluded before initiating treatment, acceptable contraceptive methods must be used, and monthly pregnancy tests should be performed.
2. Risk Evaluation and Mitigation Strategy (REMS)
All women, regardless of reproductive potential, must enroll in the Ambrisentan REMS before starting Ambrisentan treatment. Male patients are not included in the REMS. Women of reproductive potential must comply with pregnancy testing and contraception requirements.
3. Fluid Retention
If clinically significant fluid retention occurs (with or without weight gain), further evaluation should be conducted to determine the cause (e.g., Ambrisentan use or underlying heart failure) and whether special treatment or discontinuation of Ambrisentan is necessary.
4. Pulmonary Edema Associated with Pulmonary Venous Occlusive Disease (PVOD)
If a patient develops acute pulmonary edema after initiating treatment with a vasodilator such as Ambrisentan, the possibility of PVOD should be considered. If PVOD is confirmed, Ambrisentan should be discontinued.
5. Decreased Sperm Count
Ambrisentan may have an adverse effect on spermatogenesis. Patients are advised to consult a doctor regarding the potential impact of Ambrisentan on fertility.
6. Hematological Changes
Measure hemoglobin one month before initiating Ambrisentan treatment, and then at regular intervals thereafter. It is not recommended to initiate Ambrisentan treatment in patients with clinically significant anemia. If a clinically significant decrease in hemoglobin is observed and other causes are ruled out, consideration should be given to discontinuing Ambrisentan.
(VII) Therapeutic Efficacy
1. Study Design
This was a prospective, multicenter, open-label study in which treatment-naive patients with Child-Pugh Class A/B portopulmonary hypertension (PoPH) received Ambrisentan for 24 weeks, followed by a long-term extension phase (24-28 weeks).
2. Study Outcome Measures
The primary outcome measures were changes in pulmonary vascular resistance (PVR) and 6-minute walk distance (6MWD) at 24 weeks. Secondary endpoints included safety, World Health Organization (WHO) Functional Class (FC), and echocardiographic assessments.
3. Study Results
There was a significant reduction in PVR, while 6MWD remained unchanged. Other hemodynamic parameters, such as right atrial pressure, mean pulmonary arterial pressure, and cardiac index, showed improvements, while pulmonary capillary wedge pressure remained unchanged. Monotherapy with Ambrisentan improved hemodynamics and FC in patients with PoPH at 24 weeks.
(VIII) Drug Interactions
Multiple-dose co-administration of Ambrisentan and cyclosporine resulted in an approximately 2-fold increase in Ambrisentan exposure in healthy volunteers. When co-administered with cyclosporine, the dose of Ambrisentan should be limited to 5 mg once daily.
(IX) Storage Conditions
Store at 20°C to 25°C (68°F to 77°F); excursions between 15°C and 30°C (59°F and 86°F) are permitted. Ambrisentan should be kept in its original packaging.
Friendly Reminder: The package inserts of some products are updated frequently. Please refer to the actual product for the most accurate information.
