Durvalumab is an immunotherapy medication that harnesses the body’s own defense mechanisms to combat certain types of lung cancer. This drug functions by helping the immune system to recognize and attack cancer cells more effectively.
How Durvalumab Works
Immunotherapy empowers the body’s immune system to fight cancer, unlike treatments that directly target cancer cells with chemicals or radiation. Cancer cells often develop ways to evade immune detection, and Durvalumab helps to counteract this evasion. The drug specifically targets a protein called PD-L1 (Programmed Death-Ligand 1), which can be found on the surface of some cancer cells and cells within the tumor’s surroundings.
PD-L1 interacts with another protein called PD-1 (Programmed Death-1), located on immune cells known as T-cells. This interaction normally acts as a “brake” on the immune system, preventing T-cells from attacking healthy cells. Cancer cells exploit this pathway by displaying PD-L1, effectively telling T-cells to leave them alone.
Durvalumab is a type of antibody designed to block the interaction between PD-L1 on cancer cells and PD-1 or CD80 on T-cells. By binding to PD-L1, Durvalumab prevents this “off” signal, releasing the brakes on T-cells. This allows T-cells to reactivate, recognize cancer cells as foreign, and launch an attack against them, leading to tumor destruction.
Lung Cancers Treated with Durvalumab
Durvalumab is approved for use in two main types of lung cancer: Non-Small Cell Lung Cancer (NSCLC) and Small Cell Lung Cancer (SCLC).
For non-small cell lung cancer, Durvalumab is specifically used in patients with unresectable Stage III disease. This means the cancer has not spread widely but cannot be completely removed by surgery. In this setting, Durvalumab is given as a “consolidation” therapy after patients complete concurrent chemoradiation therapy. Eligibility for Durvalumab in NSCLC involves testing for PD-L1 expression on tumor cells, with higher expression indicating a greater likelihood of benefit.
In extensive-stage small cell lung cancer, a more aggressive form where the cancer has spread extensively, Durvalumab is used as a first-line treatment. It is given in combination with platinum-based chemotherapy (carboplatin or cisplatin, along with etoposide). This combination therapy aims to improve overall survival compared to chemotherapy alone. Unlike NSCLC, PD-L1 testing is not a requirement for Durvalumab use in extensive-stage SCLC.
Receiving Durvalumab Treatment
Durvalumab is administered as an intravenous infusion. These infusions are given in a medical setting, such as a doctor’s office or an infusion center. Each infusion takes about 60 minutes to complete.
The frequency of Durvalumab administration can vary depending on the type of lung cancer being treated. For unresectable Stage III NSCLC, patients may receive Durvalumab either every 2 weeks or every 4 weeks. This treatment is continued for up to 12 months, or until the disease progresses or side effects become too difficult to manage. For extensive-stage SCLC, Durvalumab is administered every 3 weeks in combination with chemotherapy for four cycles, followed by maintenance therapy every 4 weeks as a single agent.
During the course of treatment, healthcare providers will regularly monitor patients through blood tests and imaging scans. Monitoring assesses treatment effectiveness and identifies side effects.
Managing Potential Side Effects
Durvalumab activates the immune system, which can sometimes lead to immune-related adverse events (irAEs) where the immune system attacks healthy tissues. These reactions can affect various organs and tissues and may occur at any time during or after treatment.
Common general side effects of Durvalumab can include fatigue, skin rash, diarrhea, and nausea. Patients might also experience cough, shortness of breath, or upper respiratory tract infections.
More serious, less common, immune-related side effects can affect specific organs. These include pneumonitis (inflammation of the lungs), colitis (inflammation of the intestines that can cause severe diarrhea or abdominal pain), and hepatitis (liver inflammation with symptoms like yellowing skin or eyes, dark urine, or unusual bleeding). Endocrinopathies affect hormone-producing glands (thyroid, adrenal, or pituitary), potentially causing symptoms such as extreme tiredness, weight changes, or headaches.
If side effects become severe, Durvalumab treatment may be paused or discontinued.