The Role of a Pharmacist in Managing irAEs

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment in the adjuvant and advanced setting by providing robust and durable treatment responses. ICIs have a variety of targets, such as the cytotoxic T lymphocyte antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1)–programmed cell death 1 ligand 1 (PD-L1) axes. These recently discovered targets have transformed clinical practice as well as the prognosis of patients with cancer, but their rapid rise to utilization has not correlated with an appropriate rise in provider and patient education about these agents and their adverse effects. As the rate of use of ICIs in clinical practice continues to climb, more patients are presenting with common as well as rare immunotherapy related adverse events (irAEs), with adverse events of any grade happening in up to 30% of patients on these agents. These irAEs require a team-based effort, with pharmacists playing an integral role in the identification and management of these toxicities within both the outpatient and inpatient multidisciplinary teams.   

The Value of the Pharmacist 

Pharmacists are uniquely situated and accessible in both acute and primary care settings, therefore making them optimally placed in practice to assist with irAEs. ICIs can have delayed adverse effects that present weeks or even months after starting therapy. For example, skin manifestations present within the initial few weeks whereas more advanced adverse effects such as hepatic and pulmonary toxicities appear on average 4 months after therapy. This variability of exhibition in combination with nonspecific symptoms provides added layers of complexity to the identification and management of these adverse effects. However, early identification and management of these adverse effects is crucial to minimize treatment delays and discontinuations and ultimately maximize a patient’s prognosis and outcomes.  

Pharmacists are at the forefront of providing seamless transitions of care, with studies showing that their involvement not only improves patient outcomes but decreases rates of hospital readmissions, thereby decreasing mortality, morbidity, and costs. Given their key role in facilitating transitions of care, pharmacists are often the best source for identifying a patient’s timeline of immunotherapy treatment. In addition, pharmacists are often well versed on the latest literature and guideline updates, and in turn are consistently consulted by physicians for drug information and toxicity management. This distinctive skillset makes pharmacists an invaluable resource on any multidisciplinary team, and an inimitable asset in the identification and management of irAEs.  

Empowerment Through Education   

Patient awareness is another crucial component to the early recognition and management of irAEs. Empowering patients through personalized education on medication dosing, toxicities, and red flags, empowers them to be proactive in their own treatment. Patients cite unaffordability and inaccessibility to care as their greatest barriers to reporting adverse effects before they develop into higher grades. Pharmacists are the most accessible and frequently visited healthcare providers, placing them in an opportune position to provide advice and education to patients beginning a new therapy in clinic, requiring follow-up care, or are in an acute setting. They are ideally situated to provide care and management for patients with health inequities and poor social determinants of health who may otherwise be unable to see a provider.

Pharmacists should be utilized to maximize patient education prior to starting a new therapy, as well as employed to provide consistent and accessible follow up for patients throughout treatment. When a patient is started on a new regimen, pharmacists can delve into key points about the new therapy such as: how to take the medication, potential side effects to be on alert for, and foods or other medications to avoid. Patients are often overwhelmed by the amount of information presented to them when beginning a new regimen, and this focused education allows the patient to focus on key points in a comprehensible format. Furthermore, pharmacists can extend their patient accessibility throughout the entirety of a patient’s treatment course by providing consistent follow-up care. At patient follow-up visits, pharmacists can monitor pertinent labs while simultaneously ensuring that the patient is appropriately adhering to their medication, review any questions that may have come up since their initial education, provide supportive care for side effects they may be experiencing, and monitor the patient for any signs of adverse effects.  

A Resource to The Care Team 

Pharmacists are not only the most accessible provider for patients, but they are also one of the most accessible providers for the multidisciplinary team. Oftentimes, when a provider is trying to deduce whether an adverse effect was related to an ICI or determine how they will manage a patient’s irAE, they will come to the pharmacist’s office and use them as a sounding board.

Given the pharmacist's expertise in drug information, literature, and transitions of care, they are looked to in both inpatient and outpatient settings to decipher a patient’s treatment timeline and determine the probability of an adverse effect being immune-related or due to another cause. Once they help a provider determine whether the adverse effect is a drug toxicity, pharmacists can be utilized to determine whether to dose reduce, hold, or stop the medication. Furthermore, pharmacists can provide recommendations on how to manage the drug toxicity as well as appropriate dosing for toxicity treatment options such as steroids, antihistamines, and gabapentinoids. Additionally, pharmacists can utilize their role to educate nurse practitioners, nurses, fellows, residents, and attendings on the most updated guidelines and literature for irAEs. This enables all providers on the care team to be up to date on best practices and provide the best care for their patients.