Obesity and metabolic trials: BMI, A1c and the GLP-1 era

Why is recruitment hard when so many adults qualify on paper?

Population numbers make these trials look easy. One analysis of national survey data estimated that 93.0 million US adults, 38 percent, fit the criteria of STEP 1, the semaglutide 2.4 mg obesity trial.^⁠[7] It applied STEP 1's BMI and comorbidity rules and excluded diabetes, acute pancreatitis, bariatric surgery and severe renal failure. That sizes the pool, not who passes screening: weight, A1c and GLP-1 use change between the last chart entry and the screening visit.

What do obesity and type 2 diabetes protocols usually require?

Most obesity trials start from a BMI rule. FDA's January 2025 draft guidance on weight-reduction drugs describes enrolling adults with a BMI of 30 or higher, or 27 or higher with a weight-related comorbidity such as type 2 diabetes, hypertension, dyslipidemia, sleep apnea or cardiovascular disease.^⁠[5] Of 10,407 registered obesity and obesity-related studies, about 75 percent used BMI as a strict inclusion criterion.^⁠[6]

Type 2 diabetes trials add an A1c window and a background-therapy rule. SURPASS-2 required an HbA1c of 7.0 to 10.5 percent and a stable metformin dose above 1,500 mg a day for at least 3 months.^⁠[8] Obesity trials that exclude diabetes turn the A1c rule around: STEP 1 excluded a central-lab HbA1c of 6.5 percent or higher.^⁠[9]

How does prior GLP-1 use affect eligibility?

Many obesity protocols exclude recent GLP-1 exposure. SELECT, the semaglutide cardiovascular outcomes trial, excluded treatment with any GLP-1 receptor agonist within 90 days before screening.^⁠[10] A Phase 3 enicepatide trial that Roche started in 2026 excludes any approved or investigational GLP-1-based therapy, whether single, dual or triple agonist, within 6 months before randomization.^⁠[11]

By late 2025, 18 percent of US adults said they had ever taken a GLP-1 drug and 12 percent were taking one, up from 12 and 6 percent in May 2024.^⁠[3],[4] Among adults told they had overweight or obesity in the past five years, 34 percent had ever taken one and 23 percent were taking one; among adults with diabetes, 57 and 45 percent.^⁠[3]

Many of those patients stop. In a large US EHR cohort of adults with overweight or obesity who started a GLP-1, 64.8 percent of those without type 2 diabetes discontinued within one year, against 46.5 percent of those with it.^⁠[12] A patient excluded today may qualify once the washout has passed, if the chart shows when the drug was stopped.

What drives screen failure in obesity and metabolic trials?

Published data here is thin: few metabolic trials report screen failures by reason, and we found no verifiable pooled screen failure rate for obesity or type 2 diabetes trials. The clearest numbers come from single trials and eligibility modeling.

SURMOUNT-3, which used a lead-in, shows two gates. Of 972 people assessed at screening, 806 entered a 12-week intensive lifestyle lead-in, so about 17 percent were not enrolled. Of those 806, 579 (71.8 percent) reached at least 5 percent weight loss, remained eligible and were randomized.^⁠[13]

A 2026 study of 352 GLP-1 receptor agonist trials registered from 2017 to 2020 found BMI criteria in 66.2 percent. In national survey data, a BMI threshold of 30 was met by 41.5 percent of non-Asian and 13.5 percent of Asian US adults, while more than 93 percent met typical A1c, eGFR and liver-function thresholds.^⁠[15] Of the criteria studied, BMI removed the most adults.

Where chart-eligible patients fail at screening

• Measured BMI under the threshold, when the chart weight is old or self-reported.
• A screening lab in the diabetes range. SURMOUNT-3 excluded an HbA1c of 6.5 percent or higher, fasting glucose of 126 mg/dL or higher, or random glucose of 200 mg/dL or higher.^⁠[13] Some of these patients have undiagnosed diabetes: 27.6 percent of US adults with diabetes do not know they have it.^⁠[2]
• GLP-1 or weight-loss drug use that the medication list did not show.
• Self-reported weight change over the limit, such as 5 kg in 90 days.^⁠[9]
• Psychiatric screening, such as a PHQ-9 score of 15 or more, an exclusion in SURMOUNT-3.^⁠[13]
• Lead-in failure, when a patient misses a weight-loss target before randomization.^⁠[13]

The chart-based items can be checked before a screening visit is booked; the central-lab result and the lead-in cannot. See the guide to reducing screen failure.

What does Bond read in the chart to find eligible patients?

Bond's Identify stage reads structured EHR data and clinical notes against a study's inclusion and exclusion criteria, ranks candidates, and links each criterion decision to the evidence behind it.^⁠[18] It also uses imaging data and other unstructured documents, including pathology, radiology and molecular reports.^⁠[19] For a metabolic protocol, that evidence falls into four groups.

1. 1

   Vitals and labs

   Height, weight, BMI and trend, plus A1c, glucose, eGFR and liver enzymes, each linked to the record it came from so a coordinator can see how old it is.

2. 2

   Medications

   Current and past GLP-1 and GIP agonists, other glucose-lowering and weight-loss drugs, with start and stop evidence from orders and notes.

3. 3

   Problem list and history

   Comorbidities, diabetes type, pancreatitis, gallbladder disease, bariatric surgery, and personal or family history of thyroid cancer.

4. 4

   Notes and reports

   Sleep studies, eye exams, psychiatric history, weight-loss attempts, and why a drug was stopped.

One drug appears under many names: semaglutide as Ozempic, Wegovy or Rybelsus, tirzepatide as Mounjaro or Zepbound, plus RxNorm codes and free text. Bond's terminology graph maps names and codes across 18 sources, including RxNorm, LOINC, SNOMED CT and ICD-10-CM, in 3,270,078 nodes, so one criterion check matches each form.^⁠[20]

How many obesity and metabolic trials are recruiting in the US?

As of September 21, 2026, a ClinicalTrials.gov condition keyword search for obesity, overweight or type 2 diabetes returned 852 recruiting studies with a US site, out of 22,041 in total.^⁠[17] The count includes observational studies, and a study can appear in more than one area.

These are keyword searches, not formal categories. The cardiology search includes hypertension and cardiovascular terms, so some metabolic studies count there too, and MASH and NASH studies fall under gastroenterology. The therapeutic areas page covers the rest.

Sponsor trials fill fast: STEP 5 randomized all 304 participants in under four months, and SURMOUNT-3 enrolled 806 people into its lead-in in under five months.^⁠[14],[13] IQVIA estimated more than 193 obesity assets in development worldwide as of October 2025.^⁠[16] Sites with candidates pre-screened at activation are better placed.

What does it take to start on a metabolic study?

Many metabolic candidates are seen in primary care, not at a research site, so Bond works with research sites and with physician groups.

Full EHR integration usually takes 48 hours, depending on the EHR, IT review and interface method. Pricing is a volume-based platform fee plus a success fee per randomized patient, with no integration fee; see pricing.^⁠[18]