II. Indications
- Melanoma (Keytruda, Nivolumab)
- Non-Small Cell Lung Cancer (Keytruda, Nivolumab)
- Hepatocellular Cancer (Nivolumab)
- Hodgkin Lymphoma (Keytruda, Nivolumab)
- Head and Neck Squamous Cell Carcinoma (Keytruda, Nivolumab)
- Urothelial Cancer (Keytruda, Nivolumab)
- Gastric Carcinoma (Keytruda)
- Microsatellite Instability high or mismatch repair deficient solid tumors (Keytruda, Nivolumab)
III. Mechanism
- See Immune Checkpoint Inhibitor
- Immune Checkpoint Inhibitors are a subtype of Monoclonal Antibody-Mediated Chemotherapy
-
Antigen Presenting Cells (APC) can inhibit T Cells via several "Checkpoints"
- In healthy patients, this T-Cell suppression prevents Autoimmune Disease
- However, cancer cells may exploit this mechanism to allow for their own propagation
- Programmed Cell Death Receptor 1 (PD-1) and its Ligand (PDL-1) are among factors that suppress T-Cell function
- PD-1 is expressed on T Cell surface and APC-B7 Binding (PD Ligand 1) inhibits the T cells
- Checkpoint Inhibitors that target the PD-1 receptor are described here
- Also see PDL-1 Monoclonal Antibody
IV. Medications
- Pembrolizumab (Keytruda)
- Nivolumab (Opdivo)
V. Dosing
- See other references for disease specific dosing protocols
VI. Adverse Effects: General Immune Checkpoint Inhibitors
- See Immune Checkpoint Inhibitors
- Precautions
- Immune Checkpoint Inhibitors counter mechanisms to prevent Autoimmunity (i.e. risking autoimmune reactions)
- Toxicity may be severe or even life threatening
- Reactions may be delayed for even a year after medication is discontinued
- Initially may be unclear that presentation is related to Immunotherapy adverse effects
- Keep a broad differential diagnosis with careful history and examination
- Consult the patient's oncologist
-
General Immunotherapy related adverse effects
- Ipilimumab (CTLA-4 inhibitor) is associated with up to 65% adverse effect rate
- Increased adverse effects with combination of Ipilimumab (CTLA-4 agent) and PD-1 or PDL-1 agents
- Adverse effects with combination therapy occur in nearly all patients and tend to be more severe
- Reactions are classified on a 4 grade scale from low grade or high grade reactions (simplified into 2 groups below)
- Low grade Immunotherapy related adverse effects
- Supportive and symptomatic care
- Localized Corticosteroids (e.g. rash, colitis) or oral Prednisone (0.5 to 1 mg/kg/day)
- High grade Immunotherapy related adverse effects (severe or life threatening)
- Hospitalization
- High dose Corticosteroids (1 to 2 mg/kg up to 4 mg/kg/day)
- Infliximab (tnf-alpha agent) or Mycophenolate have been used in steroid refractory cases
- Consider if no Corticosteroid response in 2 to 3 days
- Corticosteroids tapering over 4 to 6 weeks is started after symptoms improve
- Start Pneumocystis jirovecii prophylaxis if longterm Corticosteroids are used
- Low grade Immunotherapy related adverse effects
- Immune
- Graft Versus Host Disease
- Occurs in recipients of Hematopoietic Stem Cell Transplant
- Immune Mediated Reactions may affect any system
- Immune-Mediated Colitis
- Immune-Mediated Hepatitis
- Immune-Mediated Dermatitis
- Immune-Mediated Endocrinopathy (e.g. Thyroiditis, hypophysitis, Type 1 Diabetes Mellitus)
- Immune-Mediated Pneumonitis
- Immune-Mediated Nephritis
- Graft Versus Host Disease
- Skin reactions (34-62%)
- Pruritus
- CTLA-4 inhibitor (Ipilimumab) with onset of rash 3-6 weeks after treatment
- Morbilliform Rash
- PD-1 Inhibitor (e.g. Atezolizumab) with onset of rash at 4-10 months after treatment
- Lichenoid Dermatitis
- Eczematous Dermatitis
- Vitiligo
-
Diarrhea or colitis (up to 44-46% of cases, esp. combination therapy)
- Exclude Clostridium difficile and CMV-Associated Diarrhea (and obtain CT Abdomen if significant Abdominal Pain)
- Onset typically 5-8 weeks after treatment
- Earlier onset and worse with CTLA-4 inhibitor than with PD-1 Inhibitors
- Treat symptomatically
- Loperamide may be used if infection has been excluded (e.g. Clostridium difficile, CMV-Associated Diarrhea)
- Hepatotoxicity
- Evaluate for Viral Hepatitis and Alcoholic Hepatitis
- Occurs in <2% of monotherapy but 17% of combination therapy (CTLA-4 inhibitor with PD-1 Inhibitor)
- Onset 6 weeks after starting CTLA-4 inhibitor and 12 weeks after starting PD-1 Inhibitor
- Mycophenolate Mofetil has been used in severe hepatotoxicity
- Endocrine Effects
- Autoimmune Thyroid Dysfunction resulting in Thyroiditis, Hypothyroidism or Hyperthyroidism (24%)
- Hypophysitis with anterior pituitary deficiency (esp. Hypothyroidism)
- Type I Diabetes Mellitus
- Adrenalitis and Adrenal Insufficiency
- Pneumonitis
- Life threatening condition, occurs in 3% of monotherapy but 10% of combination therapy (CTLA-4 with PD-1)
- Often treated initially as Pneumonia until able to distinguish from pneumonitis
- Presents as cough, fever, Hypoxemia and in some cases Respiratory Failure
- Start with Chest XRay, but best diagnosed on CT Chest
- Onset 2.5 months after starting treatment
-
Myocarditis
- Presents with Chest Pain, Dysrhythmia and in some cases Cardiogenic Shock
- Obtain EKG, Troponin and ntBNP (MRI heart with biopsy may be needed for diagnosis)
-
Hypersensitivity
- Older monoclonal antibodies were produced in mice and resulted in Hypersensitivity
- Newer drugs use a greater percentage of human antibodies (65-100%)
- Corticosteroids tapered over a 4-6 week course may be needed
- Other reactions
- Nephritis and Renal Insufficiency
- Neurologic adverse effects (e.g. Encephalitis)
- Ophthalmic adverse effects
- Vasculitis
- Myositis
- Arthritis
- References
VII. Safety
- Avoid in Lactation
- Avoid in pregnancy (all trimesters, Pregnancy category X)
- Use reliable Contraception
VIII. Resources
- Pembrolizumab (DailyMed)
- Nivolumab (DailyMed)
- American Cancer Society
IX. References
- (2024) Presc Lett 31(3): 17
- Jansson and Pallin (2020) Crit Dec Emerg Med 34(4): 19-28
- Dine (2017) Asia Pac J Oncol Nurs 4(2): 127–135 [PubMed]
- Smith (2021) Am Fam Physician 103(3): 155-63\ [PubMed]