Avatrombopag instructions

1. Generic name: Avatrombopag

Product name:Doptelet/Su Kexin

Full names: avatrombopag maleate, avatrombopag, avatrombopag

2. Indications:

1. Thrombocytopenia in patients with chronic liver disease (CLD): Avatrombopag is suitable for the treatment of thrombocytopenia in adult patients with chronic liver disease who plan to undergo surgery.

2. Thrombocytopenia in patients with chronic immune thrombocytopenia (ITP): Avatrombopag is indicated for the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia who have had an inadequate response to previous treatment.

3. Usage and dosage:

1. Management: Obtain platelet counts from patients before avatrombopag treatment and on the day of surgery to ensure appropriate increases in platelet counts. Platelet counts were assessed weekly until a stable platelet count was ≥50 × 109/L, then platelet counts were obtained monthly. After discontinuing avatrombopag, obtain platelet counts weekly for at least 4 weeks. Do not use avatrombopag to normalize platelet counts.

2. Recommended dosage:

(1) Chronic Liver Disease (CLD): Begin Avatropopag administration 10 to 13 days before planned surgery. The recommended daily dose is based on the patient's platelet count before planned surgery. The dosage for patients with less than 40×109/L is 60 mg (3 tablets) once a day for 5 days; the dosage for patients with platelet count between 40-50×109/L is 40 mg (2 tablets) once a day for 5 days. Patients should have surgery 5 to 8 days after the last dose of avatropopag.

(2) Chronic immune thrombocytopenia (ITP): If necessary, use the lowest dose of avatrombopag required to achieve and maintain a platelet count ≥50 × 109/L to reduce the risk of bleeding. Dose adjustments are based on platelet count response, starting with avatrombopag at a dose of 20 mg (1 tablet) once daily with food.

(3) Discontinuation:If the platelet count does not increase to ≥50×109/L after 4 weeks of administration, discontinue avatropopag . The maximum dose is 40 mg once daily. If the platelet count is >400×109/L after 2 weeks of 20 mg administration once a week, discontinue avatropopag.

3. Combined medication: If combined with a moderate or strong dual inhibitor of CYP2C9 and CYP3A4, take avatropopag 20 mg (1 tablet) three times a week; if combined with a moderate or strong dual inducer of CYP2C9 and CYP3A4, take 40 mg of avatropopag (2 tablets) once a day.

4. Adverse reactions:

In clinical studies of avatrombopag, the most common adverse reactions reported by at least3% of patients were fever, abdominal pain, nausea, headache, fatigue and peripheral edema. Hyponatremia was also a rare serious side effect of the drug. Adverse reactions leading to discontinuation include anemia, pyrexia, and myalgia. After avatrombopag was marketed, adverse events including allergic reactions including pruritus, rash, choking sensation, erythema, pharyngeal edema, general itching, macules, facial swelling, and tongue swelling also occurred.

5. Storage:

Avatrombopag will be stored20°C to 25°C (68°F to 77°F), with an allowed excursion in the range of 15°C to 30°C (59°F to 86°F). Avatrombopag is usually stored in its original packaging.

6. Taboo:

None.

7. Special groups:

1. Women: Because children who are breastfed with avatrombopag may experience serious adverse reactions, it is not recommended to breastfeed during treatment with avatrombopag and for at least 2 weeks after the last dose, and lactating women should pump and discard breast milk to minimize contact with breastfed children.

8. Mechanism of action:

Avatrombopag is an orally bioavailable small moleculeTPO receptor agonist that stimulates the proliferation and differentiation of megakaryocytes in bone marrow progenitor cells, thereby increasing platelet production. Avatrombopag does not compete with TPO for binding to the TPO receptor and has an additive effect with TPO on platelet production.

The original drug of avatrombopag has been launched in China and has entered the scope of Class B medical insurance, but it is only reimbursed for eligible patients. The price of a common specification of 20mg*15 tablets may be more than 7,000 yuan per box, while the original drug of avatrombopag marketed overseas is even more expensive. It is understood that there are generic drugs of avatrombopag available overseas, and their pharmaceutical ingredients are basically the same as those of the original drug. For example, the price of a box of 20mg*30 tablets in Laos pharmaceutical production specifications may be around RMB 1,000 (the price may fluctuate due to exchange rates).