Impact of VA Hematology/Oncology Clinical Pharmacy Practitioners in the Review of Community Prescriptions for Specialty Medications

RESULTS

A total of 221 hematology/oncology prescriptions met inclusion criteria. Among patients receiving these prescriptions, the median age was 70 years and 91% were male. The most common malignancies included 31 instances of multiple myeloma (14%), 26 for chronic lymphocytic leukemia (12%), 24 for prostate cancer (11%), 23 for glioblastoma/brain cancer (10%), 18 for renal cell carcinoma (8%), 17 for colorectal cancer (8%), and 15 for acute myeloid leukemia (7%). Clinical interventions by the hematology/oncology CPP were completed for 82 (37%) of the 221 prescriptions. One clinical intervention was communicated directly to the patient, and attempts were made to communicate with the community care HCP for the remaining 81 prescriptions. The CPP documented 97 clinical interventions for the 82 prescriptions (Table 1). The most commonly documented clinical interventions included: 25 for managing/preventing a drug interaction (26%), 24 for dose adjustment request (25%), 13 for prescription denial (13%), and 11 for requesting the use of a preferred or more cost-effective product (11%). Of note, 16 patients (7%) received counseling from the hematology/oncology CPP. Ten patients (5%) received counseling alone with no other intervention and did not meet the definition of a clinical intervention.

The most frequent prescriptions requiring intervention included 8 for enzalutamide, 7 for venetoclax, 6 for ibrutinib, and 5 each for lenalidomide, cabozantinib, and temozolomide. Among the 97 interventions, 68 were approved (70%), 15 received no response (16%), and 14 were denied by the community care HCP (14%). Despite obtaining no response or intervention denial from the community care HCP, hematology/oncology CPPs could approve these prescriptions if clinically appropriate, and their reasoning was documented. Table 2 further describes the types of interventions that were denied or obtained no response by the community care practitioner. Among the prescriptions denied by the hematology/oncology CPP, 11 were rejected for off-label indications and/or did not have support through primary literature, national guidelines, or VA criteria for use. Only 2 prescriptions were denied for safety concerns.

These documented clinical interventions had financial implications. For drugs with available cost data, requesting the use of a preferred/cost-effective product led to estimated savings of at least $263,536 over the study period with some ongoing cost savings. Prescription denials led to further estimated savings of $186,275 per month, although this is limited by the lack of known costs of alternative therapies the community care physicians chose.

DISCUSSION

More than one-third of prescriptions required clinical interventions, and 70% of these interventions were accepted by the community care prescriber, demonstrating the CPP’s essential role. Results indicate that most CPP clinical interventions involved clarifying and correcting doses, managing pertinent drug interactions, and ensuring appropriate use of medications according to clinical and national VA guidelines. Other studies have examined the impact of CPPs on patient care and cancer treatment.^5,6 The randomized, multicenter AMBORA trial found that clinical pharmacist support reduced severe AEs and medication errors related to oral anticancer agents.⁵ The per-patient mean number of medication errors found by pharmacist review was 1.7 (range, 0 to 9), with most medication errors noted at the prescribing stage.⁵ Suzuki and colleagues analyzed data from 35,062 chemotherapy regimens and found that 53.1% of the chemotherapy prescriptions were modified because of pharmacist interventions.⁶ The most common reason for prescription modifications was prescription error.

Most of the clinical interventions in this study were accepted by community HCPs, indicating that these prescribers are receptive to hematology/oncology CPP input. Among those with no response, most were in relation to recommendations regarding drug interactions. In most of these cases, the drug interaction was not clinically concerning enough to require a response before the CPP approved the prescription. Therefore, it is unknown whether the outside HCP implemented the clinical recommendations. The most common types of clinical interventions the community care HCP declined were dose adjustment requests or requests to switch to a more cost-effective/formulary-preferred agent. In these cases, the prescriber’s preference was documented and, if clinically appropriate, approved by the CPP.

Although the financial implications of CPP clinical interventions were only marginally evaluated in this review, results suggest that cost savings by requests to switch to a cost-effective/formulary preferred agent or prescription denials are substantial. Because of changes in prescription costs over time, it is possible that savings from CPP intervention were greater than calculations using current Federal Supply Schedule Service pricing. The total impact of CPP prescription interventions on reducing or preventing hospitalizations or AEs is not known from this review, but other data suggest that cost savings may benefit the system.^13,14