Oncology Pharmacists Reduce Adverse Drug Reactions in Hematologic Cancer Care

Integrating a dedicated oncology pharmacist into outpatient hematologic cancer care was associated with a substantial reduction in adverse drug reactions (ADRs), according to findings from a randomized clinical trial involving 182 patients. The results provide evidence that pharmacist involvement can improve medication safety in a treatment setting where complex regimens and therapy-related toxicities require ongoing clinical oversight.¹

Patients receiving pharmacist-led care experienced ADRs at approximately half the rate observed with standard care. A subsequent economic evaluation also suggested that the intervention could be a cost-effective approach to preventing medication-related harm, strengthening the case for more consistent pharmacist integration within hematology-oncology teams.²

Pharmacist Intervention Significantly Reduces Adverse Reactions

The single-center randomized trial, conducted between July 2020 and October 2022, assigned 91 patients to comprehensive pharmaceutical care delivered by a designated oncology pharmacist and 91 to standard care. The intervention included medication assessments, patient counseling, and treatment recommendations communicated directly to physicians. Outcomes were evaluated over a 4-month intervention period and an additional month of follow-up.¹

At least 1 ADR occurred in 23.1% of patients receiving pharmacist intervention compared with 47.3% in the control group, representing an absolute risk reduction of 24.2 percentage points. The age-adjusted hazard ratio (aHR) for experiencing an ADR was 0.38 (95% CI, 0.23-0.65; P < .001).¹

The intervention was also associated with fewer moderate or severe ADRs, which occurred in 5.5% of patients receiving pharmacist care compared with 19.8% receiving standard care (aHR, 0.25; 95% CI, 0.09-0.67; P = .006). These findings suggest that pharmacist involvement can influence both the frequency and severity of medication-related complications.¹

Medication Reviews Identify Preventable Safety Risks

Beyond reducing ADRs, the pharmacist identified medication-related problems that might otherwise have gone unaddressed during routine care.

Across the intervention group, the pharmacist issued 588 treatment recommendations, approximately 95% of which were implemented by physicians. Investigators classified 287 identified problems as medication errors, including errors considered potentially serious.¹

The intervention group also had a higher rate of detected medication administration errors, reflecting the additional opportunities for identifying problems through dedicated medication review rather than evidence of poorer medication safety.

These findings reinforce the value of pharmacist participation before medication-related problems result in patient harm. In hematologic malignancies, where patients frequently receive therapies requiring close toxicity monitoring, early identification of prescribing concerns and administration errors can support safer treatment delivery.

Economic Findings Strengthen the Case for Integration

A separate economic analysis of the same randomized trial examined the financial implications of providing dedicated oncology pharmacy services.

The estimated pharmacist program cost was $105 per patient across the 5-month study period. Investigators calculated an incremental cost-effectiveness ratio of $434 per ADR avoided, with a bootstrap 95% confidence interval of $281 to $956.²

Emergency department visits occurred in 28.6% of patients receiving pharmacist care compared with 37.4% of controls, while hospitalization rates were 23.1% and 28.6%, respectively. Although these outcomes favored the intervention, the findings do not establish that pharmacist involvement independently produced statistically significant reductions in acute care utilization.²

Because the analysis included only pharmacist program costs and was conducted at a single center, the results should not be interpreted as demonstrating net health system savings across all practice settings.

What the Findings Mean for Hematology-Oncology Practice

The trial contributes to a growing evidence base supporting pharmacist-led medication management. A 2026 systematic review of 33 studies found that pharmacist interventions consistently improved identification and resolution of medication-related problems, although effects on broader clinical outcomes remained less certain.³

The Hematology/Oncology Pharmacy Association's 2026 scope of practice similarly emphasizes oncology pharmacists as direct patient care providers whose responsibilities extend beyond medication dispensing to active participation in treatment management.⁴

For outpatient hematology-oncology programs, the findings support evaluating how dedicated pharmacist time can be incorporated into existing clinical workflows. Medication reconciliation, toxicity assessment, and communication with prescribers represent practical opportunities to identify problems before they disrupt treatment.

The study's single-center design and relatively short follow-up limit its generalizability, particularly across institutions with different staffing resources and patient populations. Larger multicenter investigations will be needed to determine whether similar benefits can be sustained over longer treatment periods.

Nevertheless, the reduction in ADRs provides a compelling argument for recognizing oncology pharmacists as an integral component of medication safety in hematologic cancer care.

REFERENCES

1. Alabbasi AK, Green MS, Brammli-Greenberg S, et al. Role of a designated pharmacist in reducing adverse drug reaction rates and preventing potential medication errors in hematology-oncology: A randomized controlled trial. JCO Oncol Pract. 2026;22(6):1066-1074. doi:10.1200/OP-25-00158

2. Alabbasi AK, Cohen S, Green MS, et al. Economic evaluation of a designated oncology pharmacist in hemato-oncology outpatient care: A randomized clinical trial. J Clin Onc. 2026;44:11063-11063. doi:10.1200/JCO.2026.44.16_suppl.11063.

3. Mohamed A, Salman B, Al Maskari R, Al-Farsi K, Yassin MA. Pharmacist-led interventions in hematological malignancies: a systematic review of clinical, process and economic outcomes. Front Pharmacol. 2026;17:1779201. doi:10.3389/fphar.2026.1779201.

4. Hematology/Oncology Pharmacy Association. 2026 scope of the oncology pharmacist provider. Accessed October 21, 2026. https://www.hoparx.org/resources/guidelines-standards-and-summaries/