Drug Overview

Alflutinib mesylate (also widely known by its research name AST2818 or its generic name furmonertinib) is a highly advanced, experimental cancer medicine. In the medical field, it is classified as a “Targeted Therapy” or a “Smart Drug.” Unlike older chemotherapy that attacks all fast-growing cells, this medication is designed to find and block specific broken proteins inside cancer cells.

Currently, alflutinib mesylate is an investigational drug in the United States and Europe. This means you cannot get it at a standard pharmacy yet. However, it is making major headlines in global clinical trials for its ability to treat lung cancer, especially lung cancer that has spread to the brain or has rare genetic mutations. Because of its high potential, the US FDA has granted it a special “Breakthrough Therapy Designation.”

Generic Name: Alflutinib mesylate (also known as furmonertinib or AST2818)
US Brand Names: None (Currently an investigational drug in the US; approved under a brand name in China)
Drug Class: Third-Generation Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitor / Targeted Therapy
Route of Administration: Oral (Tablet)
FDA Approval Status: Not FDA Approved for general use yet. It is actively being evaluated in Phase II and Phase III clinical trials globally.

What Is It and How Does It Work? (Mechanism of Action)

To understand how alflutinib mesylate works, we need to look at the outside of a lung cancer cell.

Many lung cancer cells are covered in tiny antenna-like structures called Epidermal Growth Factor Receptors (EGFR). Normally, these antennas tell the cell to grow and divide when the body needs it to. But in some lung cancers, a piece of DNA breaks, causing a mutation in the EGFR antenna. This broken antenna gets stuck in the “on” position, constantly sending a signal to the cell’s command center to multiply out of control.

Alflutinib mesylate is a tiny molecule that enters the bloodstream and hunts for these broken EGFR antennas. When it finds one, it locks itself directly into the antenna’s battery pack (a specific binding pocket). Unlike older drugs that might fall off, alflutinib binds irreversibly—meaning it permanently plugs up the antenna. This shuts down the cell’s major communication lines (the PI3K/AKT and MAPK pathways). Without the constant signal to grow, the cancer cells stop dividing and die.

One of the most important features of alflutinib mesylate is its ability to cross the blood-brain barrier.

The human brain has a natural, tightly woven shield that blocks most toxins and drugs from entering. Unfortunately, cancer cells can hide behind this shield. Alflutinib is specially engineered to slip through this barrier, allowing it to hunt down and destroy lung cancer tumors that have spread to the brain.

FDA Approved Clinical Indications

Important Note: Because alflutinib mesylate is an experimental medication in Western markets, it does not currently have official FDA approvals for general public use. However, it is being actively tested in clinical trials for the following investigational oncological uses:

Treatment of locally advanced or metastatic Non-Small Cell Lung Cancer (NSCLC) with common EGFR mutations (like Exon 19 deletions or L858R).
Treatment of NSCLC that has become resistant to older drugs because it developed a new mutation called T790M.
First-line treatment of advanced NSCLC that has rare, difficult-to-treat mutations known as EGFR Exon 20 insertion mutations.

Non-oncological uses:

None. This drug is strictly being researched for cancer treatment.

Dosage and Administration Protocols

Because alflutinib mesylate is an investigational drug, the exact dosage is decided by clinical trial rules. Doctors have studied several doses to find the perfect balance between killing the cancer and keeping the patient safe.

Patient Age/Type	Route of Administration	Standard Trial Dose	Frequency	Special Instructions
Adults (Common Mutations)	Oral Tablet	80 mg	Once daily	Can be taken with or without food.
Adults (Exon 20 Mutations or Brain Tumors)	Oral Tablet	160 mg to 240 mg	Once daily	Higher doses are used for rare mutations to ensure enough drug reaches the tumor.

Dose Adjustments

Renal Insufficiency (Kidney Issues): Standard dose adjustments for kidney disease are still being studied. Trial doctors will closely monitor kidney blood tests.
Hepatic Insufficiency (Liver Issues): This drug is processed by the liver. Patients with mild liver issues are watched closely. If a patient develops serious liver inflammation during the trial, the doctor will either lower the daily dose or temporarily pause the medication until the liver recovers.

Clinical Efficacy and Research Results

Recent clinical trial data (from 2020 to 2025) has shown extremely positive numerical results, leading to the drug’s FDA Breakthrough Therapy status.

Rare Mutations (FAVOUR Trial): For patients with the rare “Exon 20 insertion” mutation who had never been treated before, a massive 78.6% of patients saw their tumors shrink significantly when taking the 240 mg daily dose. Furthermore, the disease control rate (the percentage of patients whose cancer stopped growing or shrank) was a remarkable 100% in this group.
Common Mutations (FURLONG Trial): In large phase 3 trials comparing alflutinib to older targeted therapies (like gefitinib), patients on alflutinib lived without their cancer growing for a median of 20.8 months, compared to only 11.1 months on the older drug.
Brain Metastases: In trials where patients already had cancer spread to their brain, alflutinib successfully shrank the brain tumors, protecting the brain much better than first-generation drugs.

Safety Profile and Side Effects

Because targeted therapies block specific pathways that healthy cells also sometimes use (like the skin and the gut), they come with a specific set of side effects.

No Black Box Warning

There is no FDA Black Box Warning for alflutinib mesylate, as it is still in the investigational phase.

Common Side Effects (Occur in >10% of patients)

Diarrhea: The most common stomach-related side effect.
Skin Rash: Red, dry, or itchy skin breakouts.
Fatigue: Feeling unusually tired or weak.
Elevated Liver Enzymes: Blood tests showing the liver is working hard to process the medicine.
Stomatitis: Painful sores or redness inside the mouth.

Serious Adverse Events (Occur rarely)

Interstitial Lung Disease (ILD) / Pneumonitis: A dangerous and potentially life-threatening inflammation and scarring of the lung tissue itself.
QTc Prolongation: A change in the electrical rhythm of the heart, which can cause dangerous irregular heartbeats.
Severe Hepatotoxicity: Serious liver damage.

Side Effect Management Strategies

For Diarrhea: Doctors recommend keeping an over-the-counter anti-diarrhea medicine (like loperamide) at home. Take it at the first sign of loose stools and drink plenty of clear fluids.
For Skin Rashes: Use thick, alcohol-free, and unscented moisturizing creams every day. Avoid long, hot showers and wear sunscreen when going outside.
For Lung Symptoms: If you develop a new, unexplained cough or sudden shortness of breath, call your doctor immediately. This could be a sign of lung inflammation (ILD) and requires the drug to be stopped.

Research Areas

Alflutinib mesylate is a major focus in the research area of overcoming drug resistance. Because cancer cells are smart, they often mutate again to hide from medications. Scientists are actively testing alflutinib combined with other experimental therapies (like IN10018) to block the cancer from finding new escape routes. There is currently no significant research linking this specific drug to stem cell therapies or regenerative medicine, as its primary goal is to stop cancer cell growth.

Patient Management and Practical Recommendations

Pre-Treatment Tests to be Performed

Tumor Genetic Testing: A doctor must biopsy the tumor (or perform a special blood test) to confirm it has the exact EGFR mutations that alflutinib targets. Without these mutations, the smart drug will not work.
Electrocardiogram (ECG): To check the electrical activity of the heart and ensure there is no starting QTc prolongation.
Liver and Kidney Panels: Blood tests to make sure the major organs are healthy enough for a clinical trial.

Precautions During Treatment

Drug Interactions: Alflutinib interacts with an enzyme in the liver called CYP3A4. Taking certain medicines (like anti-fungal pills or even St. John’s Wort) can dangerously change the amount of cancer drug in your blood.

Do’s and Don’ts

DO ask your oncologist if there is a clinical trial testing alflutinib (furmonertinib) that you might qualify for, especially if you have an EGFR Exon 20 insertion mutation.
DO take the pill at the same time every day to keep a steady amount of medicine in your body.
DO use highly effective birth control while on this medication, as it can cause severe harm to an unborn baby.
DON’T start any new prescription medicines, vitamins, or herbal supplements without explicitly telling your clinical trial team.
DON’T eat grapefruit or drink grapefruit juice, as it can block your liver from processing the drug correctly, leading to a toxic buildup of medicine in your body.

Legal Disclaimer

The information provided in this guide is for educational and informational purposes only and does not constitute medical advice. It should not be used to diagnose, treat, cure, or prevent any disease or health condition. Always consult with a qualified healthcare professional or your treating oncologist regarding specific medical concerns, clinical trial eligibility, treatment options, or before starting, stopping, or altering any medication regimen. Every patient’s medical situation is unique, and therapies should be customized by a licensed physician.