Lorlatinib is an active pharmaceutical ingredient (API) that targets ALK (anaplastic lymphoma kinase) and ROS1 rearrangements. It’s commonly prescribed for patients whose cancer has progressed on first- or second-generation ALK inhibitors.

• Drug class: Antineoplastic agent (ALK/ROS1 inhibitor)

• Dosage form: Oral tablet

• Prescription status: Prescription-only anticancer medicine

How Lorlatinib Works (Mechanism of Action)

Lorlatinib blocks abnormal ALK and ROS1 signaling pathways that drive cancer cell growth. It was engineered to:

• Inhibit multiple ALK resistance mutations

• Penetrate the blood–brain barrier, making it effective against brain metastases

• Suppress cancer cell proliferation and survival

Approved Uses of Lorlatinib

Lorlatinib is primarily used for:

• ALK-positive metastatic NSCLC

• Patients who have progressed after other ALK inhibitors (e.g., crizotinib, alectinib, ceritinib)

Treatment decisions should always be guided by molecular testing and an oncologist’s recommendation.

Key Benefits

• Effective against resistant ALK mutations

• Strong central nervous system (CNS) activity

• Oral administration for convenience

• Useful in later-line therapy settings

Common Side Effects

Like many targeted cancer therapies, Lorlatinib may cause side effects. Commonly reported ones include:

• High cholesterol or triglyceride levels

• Weight gain and edema

• Fatigue

• Peripheral neuropathy

• Mood or cognitive changes

Serious side effects are less common but require close medical monitoring.

Safety & Precautions

• Regular lipid monitoring is recommended

• Patients should report neurological or mood changes promptly

• Drug interactions are possible—always review current medications with your doctor

• Not recommended during pregnancy unless clearly necessary