来法莫林(Xenleta)是治疗什么疾病的

Xenleta exerts antibacterial effects by inhibiting bacterial protein synthesis and is suitable for adults with community-acquired bacterial pneumonia.

What diseases does Xenleta treat?

It is specifically used to treat community-acquired bacterial pneumonia (CABP) in adults. The susceptible microorganisms it targets include:

1. Gram-positive bacteria: Streptococcus pneumoniae and methicillin-sensitive Staphylococcus aureus.

2. Gram-negative bacteria: Haemophilus influenzae.

3. Atypical pathogens: Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydia pneumoniae.

To reduce the development of drug-resistant bacteria, lefamorelin should only be used for infections confirmed or highly suspected to be caused by the above-mentioned susceptible bacteria.

The pictures come from public channels (such as the official website of the FDA, the official website of the original drug manufacturer, etc.) and are for reference only.

Xenleta usage and dosage

1. Recommended dose and course of treatment

Oral tablet: 600mg, once every 12 hours, the recommended course of treatment is 5 days.

When clinically necessary, patients can switch from intravenous treatment to oral tablets to complete the entire course of treatment.

2. Dose adjustment in patients with hepatic impairment

Oral tablets: Studies have not been conducted in patients with moderate (Child-Pugh Class B) or severe (Child-Pugh Class C) hepatic impairment, so use is not recommended for such patients.

3. How to take the medicine

The tablets should be taken on an empty stomach at least 1 hour before a meal or at least 2 hours after a meal. The whole tablet should be taken with enough water (about 180-240mL) and should not be crushed or broken.

4. Treatment of missed doses

If you miss a dose, you should take it as soon as possible; but if the next dose is less than 8 hours away, you should skip the missed dose and take the next dose directly as planned. Do not double the dose.

Xenleta Pharmacokinetics

1. Absorption

The average bioavailability of oral tablets is approximately 25%. A high-fat diet will significantly reduce its absorption, so it needs to be taken on an empty stomach. The peak blood concentration is reached approximately 0.88 to 2 hours after taking the drug.

2. Distribution

Lefamoren has a high binding rate to human plasma proteins (94.8%-97.1%) and a large distribution volume (about 86.1L), indicating that it is widely distributed in tissues in the body. Studies have shown that its concentration in the lung epithelial lining fluid is significantly higher than unbound plasma drug concentrations.

3. Metabolism

Lefamoren is mainly metabolized by the CYP3A4 enzyme in the liver cytochrome P450 system.

4. Excretion

After administration, the drug is mainly excreted through feces (about 77.3%) and partially through urine (about 15.5%). Its average elimination half-life is about 8 hours.

Lefamoren tablets themselves will also increase the plasma concentration of certain drugs metabolized by CYP3A4, and it is prohibited to be used in combination with CYP3A4 substrates (such as pimozide) that can prolong the QT interval.