Background <p>Randomized-controlled trials of the Complete Health Improvement Program (CHIP) were conducted before new-generation pharmacotherapies, such as GLP-1 and SGLT2 agents, were available. Other attempts to characterize the impact of CHIP since the advent of modern therapies lacked control groups. A new study is needed to evaluate the impact of CHIP on a population with access to modern pharmacotherapies.</p> Methods <p>Patients with type 2 diabetes mellitus (T2DM) were enrolled. Patients were randomly assigned to CHIP over 12&#xa0;weeks in a hybrid online/in-person format plus usual care or usual care alone, which consisted of access to standard Geisinger Health Plan diabetes-related services. Feasibility measures included recruitment, retention and participation rates. Clinical efficacy outcomes included change in HbA1c, weight, waist circumference, lifestyle survey results, and diabetes drug utilization by drug class at 3 and 6&#xa0;months versus baseline.</p> Results <p>Recruitment fell short of the targeted 60 patients (<i>N</i> = 25 enrolled, 13 and 12 patients randomized to the intervention and control groups, respectively). 69% of intervention participants who attended baseline visits completed at least 50% of classes, which was slightly below the target of ≥ 70%. Lifestyle survey participation was low but suggested improvements in nutrition, exercise, and sleep among intervention participants who did complete surveys. At 6&#xa0;months, change in HbA1c was −&#xa0;0.46% [95% CI −&#xa0;0.93, 0.01] and −&#xa0;0.58% [95% CI −&#xa0;0.95, −&#xa0;0.22] for the intervention and control groups, respectively. Patients in the intervention group collectively weaned off insulin therapy vs. escalated insulin therapy in the control group. There was a reduction in waist circumference in the intervention group compared to an increase in the control group (−&#xa0;4.65 [95% CI −&#xa0;9.71, 0.41] vs. 0.56 [95% CI −&#xa0;1.66, 2.78] inches, respectively).</p> Conclusions <p>Lifestyle and clinical data from this pilot clinical trial mostly aligned with previous studies. A larger trial is needed to confirm the benefits of CHIP for body composition, to further characterize the clinical effects of CHIP participation, and to understand interactions between lifestyle intervention and modern T2DM pharmacotherapy. Feasibility issues identified in this pilot study would need to be overcome to accomplish such a trial.</p> Trial registration <p>This study was registered with ClinicalTrials.gov on 05/20/2021. Registration number: <a href="https://clinicaltrials.gov/study/NCT04924400?term=morland&amp;rank=2">NCT04924400</a>.</p>