What are the warnings and precautions when using fezolinetant?

Fezolinetant is a drug used to relieve menopausal symptoms. Although it has outstanding therapeutic effects, like many drugs, special attention needs to be paid to its potential side effects, especially the impact on liver function. To ensure the safe use of fezonatant, patients are required to undergo a series of liver laboratory tests to assess liver function and the presence of liver injury before starting treatment.

Depending on the treatment plan, the doctor will ask the patient to undergo liver laboratory tests before starting fezonatant treatment, specifically testing the levels of transaminases (such asALT and AST) and total bilirubin. Patients who have transaminase levels ≥ 2 times the upper limit of normal (ULN) or total bilirubin levels ≥ 2 times the ULN should not start taking fezonatan. This is because elevated levels of these indicators may indicate impaired liver function, and continued use of fezonatant may increase the burden on the liver.

Patients will need monthly liver laboratory testing during the first three, six and nine months of treatment. This periodic examination can help promptly detect changes in liver function, especially some possible signs of liver damage. If during treatment, the patient develops new symptoms of discomfort, such as fatigue, loss of appetite, nausea, vomiting, itching, jaundice, lighter stool color, darker urine color, or abdominal pain, etc., these may be warning signs of liver damage. In this case, patients should immediately stop using fezolinant and seek medical advice for liver laboratory testing.

If laboratory tests reveal that the patient's transaminase level is elevated more than 5 times the ULN, or if the transaminase level is elevated more than 3 times the ULN and the total bilirubin level is more than 2 times the ULN, the patient must stop taking fezonatan immediately. For those patients with elevated transaminases exceeding 3 times the ULN, more frequent liver laboratory tests are required until relevant indicators return to normal.

Reference materials:https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=cae9f798-24f9-4580-a4fc-e6c710cbda3c