Pembrolizumab and nivolumab are checkpoint inhibitors, which are a type of immunotherapy used to treat certain types of cancer. These drugs work by blocking the PD-1 receptor on T cells, which can help the immune system recognize and attack cancer cells. While these drugs can be effective, they can also cause side effects, some of which can be serious. In this answer, we will discuss the side effects of pembrolizumab and nivolumab in detail.
Immune-related adverse events (irAEs)
Checkpoint inhibitors like pembrolizumab and nivolumab can cause immune-related adverse events (irAEs). These are side effects that occur when the immune system attacks healthy tissues in the body. IrAEs can affect any organ system, including the skin, gastrointestinal tract, liver, lungs, endocrine glands, and nervous system. The severity of irAEs can range from mild to life-threatening.
Common irAEs associated with pembrolizumab and nivolumab include fatigue, rash, pruritus (itching), diarrhea, nausea, vomiting, decreased appetite, and arthralgia (joint pain). More serious irAEs include pneumonitis (inflammation of the lungs), hepatitis (inflammation of the liver), colitis (inflammation of the colon), hypophysitis (inflammation of the pituitary gland), and adrenal insufficiency (a condition in which the adrenal glands do not produce enough hormones).
Pembrolizumab and nivolumab are given intravenously (IV), which means they are injected directly into a vein. Infusion reactions are side effects that can occur during or shortly after the infusion. Infusion reactions can include fever, chills, headache, nausea, vomiting, and hypotension (low blood pressure). Severe infusion reactions are rare but can include anaphylaxis (a severe allergic reaction) and cardiac arrest.
Fatigue is a common side effect of pembrolizumab and nivolumab. Fatigue can range from mild to severe and can affect daily activities. The cause of fatigue is not well understood, but it may be related to the immune system’s activation.
Checkpoint inhibitors can cause skin reactions, including rash, pruritus, and vitiligo (loss of skin pigment). The skin reactions are usually mild to moderate and can be managed with topical or systemic treatments. Severe skin reactions, such as Stevens-Johnson syndrome (a serious skin disorder), are rare.
Checkpoint inhibitors can cause endocrine disorders, such as hypothyroidism (an underactive thyroid gland) and hyperthyroidism (an overactive thyroid gland). These disorders can cause symptoms such as fatigue, weight gain or loss, hair loss, and changes in heart rate. Endocrine disorders are usually mild and can be managed with hormone replacement therapy.
Neurological side effects
Checkpoint inhibitors can cause neurological side effects, such as peripheral neuropathy (nerve damage), myasthenia gravis (a neuromuscular disorder), and Guillain-Barre syndrome (a rare disorder that causes muscle weakness). These side effects are rare but can be serious.
Hematological side effects
Checkpoint inhibitors can cause hematological side effects, such as anemia (low red blood cell count), thrombocytopenia (low platelet count), and leukopenia (low white blood cell count). These side effects are usually mild and do not require treatment.
Cardiovascular side effects
Checkpoint inhibitors can cause cardiovascular side effects, such as arrhythmias (irregular heartbeats) and myocarditis (inflammation of the heart muscle). These side effects are rare but can be serious.
It is important to note that not all patients will experience side effects from checkpoint inhibitors, and the severity of side effects can vary from person to person. Patients should discuss the potential side effects of these drugs with their healthcare provider before starting treatment. Patients should also report any side effects they experience to their healthcare provider promptly.
In conclusion, checkpoint inhibitors like pembrolizumab and nivolumab can cause a range of side effects, including immune-related adverse events, infusion reactions, fatigue, skin reactions, endocrine disorders, neurological side effects, hematological side effects, and cardiovascular side effects. While these drugs can be effective in treating certain types of cancer, it is important for patients to be aware of the potential side effects and to report any side effects they experience to their healthcare provider promptly.