The FDA approval of a liquid formulation of imatinib (Imkeldi) in November 2024 represents a significant advancement in addressing dosing challenges for pediatric cancer patients and adults with dysphagia. The stable, flavored, non-refrigerated formulation offers a solution to longstanding barriers that have complicated treatment delivery for vulnerable patient populations requiring this critical tyrosine kinase inhibitor.
Addressing Critical Treatment Barriers
Prior to the liquid formulation's availability, patients who could not swallow tablets faced numerous obstacles in receiving imatinib therapy. Christopher Phillips, PharmD, a resident in the Department of Pharmacy at the Children's Hospital of Philadelphia, highlighted the complexity of manipulating solid dosage forms: "We may have to take a tablet and cut it into even quarters. While working at a pharmacy, it may be easy enough for us to manipulate these tablets to come up with a dose that's appropriate for a younger patient, for example. However, when [patients go] home and a family [member has] to be able to measure these doses and make sure they are coming up with an accurate dose, that can be a challenging and daunting process for them."
Kate Gasparini, PharmD, BCOP, BCPPS, a pediatric oncology clinical pharmacy specialist at Memorial Sloan Kettering Cancer Center, emphasized the significance of this development: "Whether or not a medication is available as a liquid formulation may seem trivial, but for those of us who work every day with this patient population, we know it makes all the difference. It can truly improve the quality of life for patients and their families to have a liquid formulation that's easy to administer and readily available for a patient who has difficulty swallowing."
Safety and Workflow Improvements
The liquid formulation addresses significant safety concerns associated with manipulating solid dosage forms in clinical settings. Phillips described the challenges with crushing tablets in hospital environments: "We found that when trying to dispense it [in inpatient settings], crushing the tablet for patients who cannot take it causes it to disintegrate and create many particles in the air. Therefore, we employed a process where we have to crush the tablet in a chemotherapy hood."
The implementation of USP 800 standards has further complicated tablet manipulation, requiring additional engineering controls and protective measures. Nursing staff concerns about teratogenicity and employee exposure have led to workflow modifications, including advance ordering requirements that can delay medication administration.
Enhanced Dosing Consistency and Reduced Compounding Needs
Manufactured liquid formulations provide superior consistency compared to extemporaneous preparations. Phillips noted: "When it's coming from a manufacturer, we know there's going to be much greater consistency, and we don't have to have staff pulled away to compound these medications. Otherwise, we are adding more human factors, and thus human error, into making a custom recipe [when compounding tablets or capsules]."
The availability of a commercial liquid formulation eliminates dependence on compounding pharmacies, which may not be accessible to all patients. "Some hospitals either cannot or do not have the bandwidth to be able to compound these medications, so the lack of liquid formulations is truly an issue," Phillips explained. "For patients, we can come up with the best plan and the regimen that we have for them, but then we may be setting them up for failure if they can't find a compounding pharmacy when they're discharged."
Clinical Considerations and Patient Selection
The liquid formulation of imatinib maintains the same adverse effect profile as solid dosage forms, but presents unique considerations. Gasparini identified key factors: "A key consideration with liquid formulations is volume. For our younger patients, or even our young adult patients with dysphagia, larger volumes can oftentimes be difficult to tolerate. Another concern is palatability and taste."
The formulation's flavored and stable characteristics address palatability concerns that can impact treatment adherence. Phillips emphasized the importance of palatability in pediatric populations: "We cannot force a child to take something if it's not going to be good, or if it makes them even more nauseous."
Pharmacist Role in Treatment Optimization
Clinical pharmacists play a crucial role in optimizing liquid formulation use and supporting patient care. Gasparini described her comprehensive approach: "During those visits, I review medications, including chemotherapy agents, with patients and families, [and] I suggest modifications or adjustments to therapy in conjunction with the clinical team."
Phillips highlighted the collaborative nature of pharmaceutical care: "The overall direction in our field involves engaging multiple parties, bringing us all to the table for collaborative thinking, and developing good solutions by leveraging our different backgrounds to care for the patient."
Implications for Pediatric Oncology Care
The liquid imatinib formulation addresses a critical gap in pediatric-friendly oncology medications. The agent is indicated for several cancer types, including Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase, relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia, and myelodysplastic or myeloproliferative diseases associated with PDGFR gene rearrangements.
Gasparini noted the long-term benefits: "It's great that it is available to patients because they're on the therapy for a long time. It makes dose modifications easier, and [allows us] to administer it directly to the patients in a formulation that's easy to give."
The approval of liquid imatinib represents a meaningful advancement in personalized cancer care, providing healthcare teams with an essential tool to ensure consistent, safe, and accessible treatment delivery for patients who face swallowing difficulties or require precise pediatric dosing.
