This is a single-site cluster-randomized trial to assess efficacy and implementation outcomes of deprescribing interventions in 72 older adults with polypharmacy (PP) and curable cancers initiating chemotherapy. Oncologists (as the cluster) will enroll 6 patients each and will be randomized to either a pharmacist-led deprescribing intervention or patient education intervention. Initial focus groups with oncologists, nurses, pharmacists, primary care physicians, and patients will provide data for initial adaptations to the pharmacist-led intervention arm, and 8 patients will be enrolled as a pre-trial cohort to further refine and adapt the pharmacist-led intervention.

Polypharmacy (PP), or the concurrent use of multiple medications, affects up to 92% of older adults with cancer. It has been associated with adverse outcomes in these patients including poor adherence to and tolerance of cancer therapy, decrease in physical functioning, unplanned hospitalizations, falls, increased symptoms, and lower survival. "Deprescribing," or the planned discontinuation of medications which may be potentially unsafe or inappropriate, is an intervention strategy which has the potential to decrease PP and improve outcomes. Deprescribing has not been studied in older adults with cancer receiving chemotherapy. The proposed study will adapt and refine potentially scalable deprescribing interventions, investigate the effects of deprescribing interventions on relative dose intensity and other adverse outcomes in older adults undergoing curative-intent chemotherapy, and identify barriers and facilitators of deprescribing interventions for patients, oncologists, and pharmacists. Focus groups and interviews with pharmacists, oncologists, nurses, primary care providers, and patient advocates will allow initial adaptation of the proposed interventions. A "pre-pilot" cohort of 8 patients with PP and cancer planned to receive curative-intent chemotherapy will undergo a pharmacist-led deprescribing intervention with additional iterative adaptations. Then, 72 patients will be allocated to a pharmacist-led deprescribing intervention versus patient education intervention in a cluster-randomized trial of 12 oncologist clusters.

Inclusion Criteria:

• Be age ≥65 years;
• Have a diagnosis of malignancy including aggressive lymphoma or cancers of the breast, gastrointestinal system, genitourinary system, or lung;
• Be initiating chemotherapy, alone or in combination with other systemic antineoplastic agents, (for a period of at least 3 months) within 4 weeks of enrollment;
• Screen positive for polypharmacy (>10 medications) or potentially inappropriate medications
• Be able to read and write English;
• Be able to give informed consent, as determined by the primary oncologist, or has a legally authorized representative to sign consent in the case of cognitive impairment.

Exclusion Criteria:

• Be planned to receive a cancer treatment regimen that does not include standard cytotoxic chemotherapy (e.g., only targeted therapies, hormonal therapies, monoclonal antibody therapies, immunotherapy, etc.),
• Have surgery or radiation without concurrent chemotherapy planned within 3 months of consent,
• Have a planned referral to the geriatric oncology clinic (SOCARE) within one month of treatment initiation,
• Lack decisional capacity, if a legally authorized representative is not available to sign consent and participate in study visits and follow-up phone calls.