BACKGROUND: Adherence to antiretroviral (ARV) therapy is critical in order to achieve and maintain viral suppression and improve immune function. Clinical pharmacists and pharmacies focused on human immunodeficiency virus (HIV) have demonstrated the ability to increase ARV medication adherence and subsequently have a positive effect on these lab markers. OBJECTIVES: To evaluate the effect of an integrated health system specialty pharmacy service with a clinic-embedded, HIV-trained pharmacist and pharmacy technician on ARV medication adherence rate, viral load, and CD4 count. METHODS: This was a single-center, retrospective cohort study conducted from August 7, 2017, to June 30, 2018, at an indigent outpatient infectious disease clinic within Atrium Health (AH), a not-for-profit health system based in Charlotte, NC. The intervention group (opt-in group) received HIV patient care that involved the health system specialty pharmacy service. Once a patient was enrolled in the specialty pharmacy service, medication reconciliation was completed by the pharmacist, financial assistance and prior authorizations were completed if needed; prescriptions were delivered to the patient; and monthly refills calls were conducted to assess adherence, tolerability, and medication changes. The control group (opt-out group) received HIV patient care that did not incorporate the health system specialty pharmacy. The primary endpoints were medication adherence, viral suppression, and CD4 counts. Within-group comparisons from baseline to follow-up were made along with group-to-group comparisons. Adherence was calculated using medication possession ratio. RESULTS: For those patients using Atrium Health Specialty Pharmacy Service (AH SPS; n = 46), the overall median adherence rate was higher at 100% versus only 94% for those patients (n = 50) that opted out of the service ( < 0.01). All but 3 patients (21.7% at baseline vs. 6.5% at follow-up, = 0.03) using AH SPS reached viral suppression, and all but 1 had improved immune function with a CD4 count of 200 or greater by the end of the observation period ( = 0.03). The change in viral suppression and CD4 count of 200 or greater was not statistically improved between baseline and follow-up in those opting out of using AH SPS. When comparing the 2 groups at reaching these endpoints, there was no statistically significant difference in viral suppression and CD4 count. CONCLUSIONS: AH SPS was able to demonstrate improved ARV adherence in those patients using an integrated specialty pharmacy with an embedded pharmacy team, coordinated monthly medication delivery, and refill reminder and adherence calls. This in turn led to improved viral suppression and immune markers by the end of the observation window for patients using AH SPS. DISCLOSURES: No outside funding supported this study. The authors have nothing to disclose.