Analysis of detailed Chinese instructions and medication guide for Momelotinib

Momelotinib (Momelotinib) is a new type of oral Januskinase (JAK)1/2 Inhibitor, also has ACVR1 (activin receptor 1 type) inhibitory effect, developed by Sierra Developed by Oncology, it is used to treat anemia, splenomegaly and systemic symptoms related to myelofibrosis (Myelofibrosis, MF). The drug was approved for marketing by the US FDA in 2023 under the trade name of Ojjaara. Its innovation is that molotinib can not only improve spleen enlargement and systemic symptoms in patients with myelofibrosis, but also increase hemoglobin levels and reduce the need for blood transfusions. It is the first JAK inhibitor that combines anti-fibrosis, anti-inflammatory and anemia improvement.

1. [Basic information on drugs]

Chinese name: molotinib

English name:Momelotinib

Product name:Ojjaara

Drug categories: JAK1/2 and ACVR1Inhibitors

Indications: For the treatment of patients with moderate or high-risk myelofibrosis, including primary myelofibrosis, post-polycythemia vera myelofibrosis, or post-essential thrombocythemia myelofibrosis, who are associated with moderate to severe anemia.

Dosage form: oral tablet

Specifications:100mg, 150mg

2. [Mechanism of action and pharmacological characteristics]

Molotinib works by inhibiting the JAK1, JAK2 and ACVR1 signaling pathways. JAK-STATThe pathway plays a key role in the pathological process of myelofibrosis, and abnormal activation can lead to excessive proliferation of bone marrow cells, enhanced inflammatory response, and exacerbation of fibrosis. TraditionalJAK inhibitors such as ruxolitinib (Ruxolitinib) can improve splenomegaly and symptoms, but it often aggravates anemia. The inhibition of ACVR1 by molotinib can inhibit the synthesis of hepcidin (Hepcidin), thereby improving iron metabolism, increasing erythropoiesis, and alleviating anemia symptoms.

This dual mechanism makes molotinib the only JAK inhibitor that can simultaneously improve splenomegaly and anemia. Clinical studies, such as the MOMENTUM and SIMPLIFY trials, have shown that more than 30% of people have significantly reduced spleen volume, and more than 40% of patients have improved their transfusion dependence or even gotten rid of blood transfusions.

3. [Usage and Dosage]

Molotinib is taken orally, and the recommended dosage is:

Standard dosage: 200 mg orally once a day. It is recommended to take it with or after meals to reduce gastrointestinal discomfort.

Course of treatment: Treatment is a long-term maintenance program, and the doctor will determine the length of treatment based on the patient’s symptoms and laboratory test results.

If the patient experiences a drop in blood cell count (such as platelets<50×10⁹/L), serious infection, or abnormal liver function, the medication should be suspended, and the dose can be adjusted as appropriate after recovery. If persistent anemia or fatigue symptoms occur, erythropoietin therapy can be used or the dosage regimen can be adjusted.

4. [Adverse reactions and monitoring]

Common adverse reactions include:

Hematological reactions: anemia, thrombocytopenia, neutropenia.

Digestive system reactions: nausea, diarrhea, loss of appetite.

Systemic reactions: fatigue, headache, fever, or upper respiratory tract infection.

Abnormal liver function: Some patients may experience mild elevations ofALT and AST.

Compared to othersJAKInhibitor, molotinib has clear advantages in anemia management with lower incidence of hypohemoglobin. During the medication period, it is recommended to monitor blood routine, liver and kidney function and serum iron metabolism indicators every month, and adjust the dose or interrupt treatment if necessary.

5. [Drug Interactions]

Molotinib is mainly metabolized through the CYP3A4 metabolic pathway, so attention should be paid to drug concentration changes when used in combination with strong CYP3A4 inhibitors (such as ketoconazole, clarithromycin) or inducers (such as rifampicin, carbamazepine).

Additionally, the risk of infection should be monitored when coadministered with other immunosuppressants. Avoid use with strong antifungals, antivirals, or biologics unless specifically directed by your doctor.

6. [Notes]

Not suitable for pregnant and lactating women: Animal experiments show that this drug may have adverse effects on the fetus.

Patients with hepatic and renal insufficiency: The dosage needs to be reduced as appropriate based on clinical evaluation.

Elderly patients: Blood changes should be closely monitored to prevent infection.

Drug withdrawal reaction: Sudden drug withdrawal may cause a rebound of the condition, and should be gradually adjusted under the guidance of a doctor.

7. [Drug Prices and Drug Purchase Information]

At present, molotinib has not been officially launched in mainland China, and there is no medical insurance reimbursement policy in the country. If patients need medication, they can obtain it through formal overseas channels (such as Hong Kong licensed pharmacies or authorized agencies of international pharmaceutical companies).

According to the latest price information:

The price of the US version of the original drug: approximately 20 around 10,000 yuan (based on 200mg specification).

The Lao version of the generic drug: has been approved by the local Ministry of Health for marketing. 100mg×30 tablets are priced at about 2,000 yuan. The ingredients of the drug are basically the same as the original drug, but it still needs to be confirmed by a doctor before clinical use.

Momelotinib (Momelotinib), as the world's first JAK inhibitor that has both anti-fibrosis and anemia-improving effects, provides new treatment hope for patients with myelofibrosis. Its unique dual mechanism not only improves splenomegaly and systemic symptoms, but also significantly reduces the need for blood transfusion and improves quality of life. Although it is not yet on the market in China, with its outstanding clinical data and safety, it is expected to become the core treatment option for patients with myelofibrosis in the future. During use, patients should strictly follow the doctor's instructions and regularly monitor blood and liver function to ensure medication safety and maximize efficacy.

Reference materials:https://www.drugs.com/