Abstract Introduction Oral chemotherapy agents have become increasingly common for the treatment of various malignancies, specifically in the metastatic setting. In metastatic breast cancer, oral chemotherapy is now considered the standard of care for first-line treatment due to progression-free survival and overall survival benefits. Oral agents are also considered to be a convenient and less toxic therapy option, improving quality of life. However, these benefits are offset by challenges in the delay to initiation of therapy, adherence, and toxicity management which may lead to high co-pays, delays in treatment, increased clinic visits, and non-adherence. These issues can be augmented at a safety net hospital charged to care for the most vulnerable patients. Close monitoring and follow-up are critical but can be complex and pose an additional burden on the treating oncologist. Pharmacists can serve as an extender to the oncologist and may help mitigate many of these clinical and operational barriers through adherence strategies, toxicity management, care coordination, and optimization of dosing schedules and regimens. Methods/Materials We conducted a quality improvement (QI) initiative aimed to decrease the average number of treatment day delays experienced by patients receiving oral chemotherapy for the treatment of MBC during the first six cycles of chemotherapy. A secondary aim was to improve adherence and patient-provider satisfaction. A protocol was designed and implemented utilizing pharmacists to provide assistance with obtaining the medications through a specialty pharmacy, oral chemotherapy counseling, toxicity assessments, and strategies to help optimize oral adherence (OPTIMAL protocol). Pharmacists conducted live in-person visits and telemedicine visits at weekly to monthly intervals to supplement the ongoing routine care of the oncology provider. All treatment and supportive care recommendations, in addition to any identified barriers, were communicated to the provider. Results A baseline assessment of 63 patients receiving oral oncolytic therapy from December 1st, 2018 through November 26th, 2019 was completed. Patients experienced most delays during cycle 1, with an average of 14.5 days of delay (range 1 - 34 days). The most common reasons for delay throughout the first six cycles of therapy were toxicity development, receipt of medication from the pharmacy, and patient adherence. A separate analysis of patients on CDK4/6 inhibitors (n=8) identified an average treatment day delay of 7.7 days (range 3.2 - 15.3 days) during the first six cycles of chemotherapy. Over a 7-month period, fifteen patients were enrolled in the OPTIMAL protocol and experienced an average treatment day delay of 2.9 days (range 0 - 6.8 days) during the first six cycles. Pharmacists made 206 documented interventions amongst the patients on the protocol, encompassing medication reconciliations, therapy counseling, and clinical recommendations. Eleven patients reported treatment-related toxicities, resulting in six therapy modifications and two-dose modifications. Four patients experienced progression on oral oncolytic therapy and subsequently went on to other treatment options. Conclusion Our protocol to incorporate pharmacists in initial and follow-up clinic visits at an outpatient breast cancer clinic within a safety net hospital was associated with decreased treatment day delays. Pharmacists performed a large number of meaningful clinical and operational interventions to facilitate medication treatment in a, particularly vulnerable population. This intervention supports the valuable and versatile role pharmacists can play in co-managing patients with the rest of the healthcare team. Citation Format: Jasmine Patel, David Michael Hughes, Kathryn Quinn, Tsion Fikre, Naomi Ko. Effect of an outpatient pharmacy team to improve management and adherence to oral chemotherapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS13-26.