Abstract Body (Do not enter title and authors here): Background: Suboptimal HTN control is a widespread problem particularly among minorities and socioeconomically disadvantaged groups. Objective: To determine if a mobile health (mHealth) intervention facilitating an active partnership between inter-professional care teams (including pharmacists) and patients improves HTN control in patients with uncontrolled HTN. Methods: mGlide is an NIH-funded 2-arm RCT evaluating HTN control between a mHealth intervention (mGlide) and state-of-clinical-care (comparison) groups using a PROBE (Prospective Randomized Open Blinded End-point) Design. Table 1 shows intervention components. High CVD risk patients with uncontrolled HTN identified by EHR query were randomized 1:1 to mGlide or to comparison for a 6-month intervention followed by a 6-month observation period. . Recruitment sites included primary care clinics and specialty stroke service in an integrated health system as well as community clinics (CC) and federally qualified health centers (FQHC). The FQHC and CC serve low income patients and minority (Latino and Hmong) patients. The primary aim tested clinical effectiveness of mGlide in reducing SBP at 6 months. Secondary outcomes include resource utilization, adverse events and medication side effects. Results: Recruitment started in 2019. N=395 participants enrolled by August 2023. The pandemic impacted enrollment; enrollment recovered after vaccine availability (Figure). Primary outcome was available in March 2024 on everyone except those lost to follow-up (n=38; 9.6%). We used multiple imputation for missing 6 month BP. Baseline mean SBP was 143.2 mm Hg in mGlide arm vs. 143.6 mm Hg in comparison arm. The intervention led to better HTN control (Table 2). Mean 6-month SBP was 128.1 (mGlide) vs. 134 mm Hg (comparison). Adjusting for baseline SBP and study strata, 6-month SBP was 5.7 mm Hg (95% CI 2.9-8.4; p=0.0001) lower in mGlide vs. comparison. The odds of HTN control defined as alive and SBP < 130 mm Hg was 60% higher in the mGlide arm (OR 1.6; 95% CI 1.03-2.48; p=0.035). There was one death in each study arm. The mGlide arm had fewer ER visits (16% vs. 25%; p=0.024), fewer hospitalizations (7% vs. 13%, p=0.044) and more medication side effects (39% vs. 26%, p=0.008). Conclusions: An inexpensive mHealth intervention using the patient’s own smart phone (Table 1) was implemented in diverse health systems and significantly reduced SBP and was associated with less resource utilization at 6 months (Table 2).