Estimating and reporting treatment effects in clinical trials for weight management: using estimands to interpret effects of intercurrent events and missing data

Efficacy and safety of once-weekly semaglutide 2·4 mg versus placebo in people with obesity and prediabetes (STEP 10): a randomised, double-blind, placebo-controlled, multicentre phase 3 trial

BACKGROUND

There are currently limited data regarding the effect of semaglutide 2·4 mg in individuals with obesity and prediabetes in clinical trials. We aimed to assess the efficacy and safety of semaglutide 2·4 mg for weight management and glycaemic control in participants with obesity and prediabetes.

METHODS

STEP 10 was a randomised, double-blind, parallel-group, phase 3 trial done across 30 trial sites in Canada, Denmark, Finland, Spain, and the UK and included participants aged 18 years or older with a BMI of 30 kg/m2 or higher and prediabetes according to UK National Institute for Health and Care Excellence criteria (defined as having at least one of the following at screening: HbA1c of 6·0-6·4% [42-47 mmol/mol] or fasting plasma glucose [FPG] of 5·5-6·9 mmol/L). Participants were randomly assigned (2:1) to once-weekly subcutaneous semaglutide 2·4 mg or placebo with diet and physical activity counselling for 52 weeks, followed by a 28-week off-treatment period. Primary endpoints were percentage change in bodyweight and proportion of participants reverting to normoglycaemia (HbA1c <6·0% [<42 mmol/mol] and FPG <5·5 mmol/L) at week 52 (assessed in all randomly assigned participants by intention to treat). Selective safety data were collected for participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT05040971, and is complete.

FINDINGS

Between Sept 16 and Dec 29, 2021, 138 participants were randomly assigned to semaglutide 2·4 mg and 69 to placebo. 147 (71%) were female and 60 (29%) were male; 183 (88%) were White. All randomly assigned participants received at least one dose of study drug. Baseline mean age was 53 years (SD 11), bodyweight 111·6 kg (22·2), BMI 40·1 kg/m2 (6·9), waist circumference 120·1 cm (14·7), HbA1c 5·9% (0·3; 41·3 mmol/mol [3·0]), and FPG 5·9 mmol/L (0·6). There was a significantly greater reduction in bodyweight with semaglutide 2·4 mg than with placebo at week 52 (-13·9% [SD 0·7] vs -2·7% [0·6]; estimated treatment difference -11·2% [95% CI -13·0 to -9·4]; p<0·0001). Greater proportions of participants reverted to normoglycaemia at week 52 with semaglutide 2·4 mg than with placebo (103 [81%] of 127 vs nine [14%] of 64; odds ratio 19·8 [95% CI 8·7 to 45·2]; p<0·0001). Serious adverse events occurred in 12 (9%) participants receiving semaglutide 2·4 mg versus six (9%) receiving placebo. Adverse events leading to treatment discontinuation occurred in eight (6%) participants in the semaglutide 2·4 mg group versus one (1%) participant in the placebo group. No new safety signals were reported.

INTERPRETATION

Semaglutide 2·4 mg provided superior reduction in bodyweight and reversion to normoglycaemia versus placebo in participants with obesity and prediabetes. The safety and tolerability profile was consistent with previous studies and with the GLP-1 receptor agonist class. These findings support the potential use of semaglutide 2·4 mg as a treatment option for individuals with obesity and prediabetes to achieve reversion to normoglycaemia.

FUNDING

Novo Nordisk.

TRANSLATION

For the Spanish translation of the abstract see Supplementary Materials section.

Semaglutide vs Tirzepatide for Weight Loss in Adults With Overweight or Obesity

Importance

Although tirzepatide and semaglutide were shown to reduce weight in randomized clinical trials, data from head-to-head comparisons in populations with overweight or obesity are not yet available.

Objective

To compare on-treatment weight loss and rates of gastrointestinal adverse events (AEs) among adults with overweight or obesity receiving tirzepatide or semaglutide labeled for type 2 diabetes (T2D) in a clinical setting.

Design, Setting, and Participants

In this cohort study, adults with overweight or obesity receiving semaglutide or tirzepatide between May 2022 and September 2023 were identified using electronic health record (EHR) data linked to dispensing information from a collective of US health care systems. On-treatment weight outcomes through November 3, 2023, were assessed. Adults with overweight or obesity and regular care in the year before initiation, no prior glucagon-like peptide 1 receptor agonist receptor agonist use, a prescription within 60 days prior to initiation, and an available baseline weight were identified. The analysis was completed on April 3, 2024.

Exposures

Tirzepatide or semaglutide in formulations labeled for T2D, on or off label.

Main Outcomes and Measures

On-treatment weight change in a propensity score-matched population, assessed as hazard of achieving 5% or greater, 10% or greater, and 15% or greater weight loss, and percentage change in weight at 3, 6, and 12 months. Hazards of gastrointestinal AEs were compared.

Results

Among 41 222 adults meeting the study criteria (semaglutide, 32 029; tirzepatide, 9193), 18 386 remained after propensity score matching. The mean (SD) age was 52.0 (12.9) years, 12 970 were female (70.5%), 14 182 were white (77.1%), 2171 Black (11.8%), 354 Asian (1.9%), 1679 were of other or unknown race, and 9563 (52.0%) had T2D. The mean (SD) baseline weight was 110 (25.8) kg. Follow-up was ended by discontinuation for 5140 patients (55.9%) receiving tirzepatide and 4823 (52.5%) receiving semaglutide. Patients receiving tirzepatide were significantly more likely to achieve weight loss (≥5%; hazard ratio [HR], 1.76, 95% CI, 1.68, 1.84; ≥10%; HR, 2.54; 95% CI, 2.37, 2.73; and ≥15%; HR, 3.24; 95% CI, 2.91, 3.61). On-treatment changes in weight were larger for patients receiving tirzepatide at 3 months (difference, -2.4%; 95% CI -2.5% to -2.2%), 6 months (difference, -4.3%; 95% CI, -4.7% to -4.0%), and 12 months (difference, -6.9%; 95% CI, -7.9% to -5.8%). Rates of gastrointestinal AEs were similar between groups.

Conclusions and Relevance

In this population of adults with overweight or obesity, use of tirzepatide was associated with significantly greater weight loss than semaglutide. Future study is needed to understand differences in other important outcomes.

Addressing missing outcome data in randomised controlled trials: A methodological scoping review

BACKGROUND

Missing outcome data is common in trials, and robust methods to address this are needed. Most trial reports currently use methods applicable under a missing completely at random assumption (MCAR), although this strong assumption can often be inappropriate.

OBJECTIVE

To identify and summarise current literature on the analytical methods for handling missing outcome data in randomised controlled trials (RCTs), emphasising methods appropriate for data missing at random (MAR) or missing not at random (MNAR).

STUDY DESIGN AND SETTING

We conducted a methodological scoping review and identified papers through searching four databases (MEDLINE, Embase, CENTRAL, and CINAHL) from January 2015 to March 2023. We also performed forward and backward citation searching. Eligible papers discussed methods or frameworks for handling missing outcome data in RCTs or simulation studies with an RCT design.

RESULTS

From 1878 records screened, our search identified 101 eligible papers. 90 (89%) papers described specific methods for addressing missing outcome data and 11 (11%) described frameworks for overall methodological approach. Of the 90 methods papers, 30 (33%) described methods under the MAR assumption, 48 (53%) explored methods under the MNAR assumption and 11 (12%) discussed methods under a hybrid of MAR and MNAR assumptions. Control-based methods under the MNAR assumption were the most common method explored, followed by multiple imputation under the MAR assumption.

CONCLUSION

This review provides guidance on available analytic approaches for handling missing outcome data, particularly under the MNAR assumption. These findings may support trialists in using appropriate methods to address missing outcome data.

Effect of combined GLP-1 analogue and bupropion/naltrexone on weight loss: a retrospective cohort study

OBJECTIVE

Little is known about the effect of a multi-drug weight loss strategy in obesity treatment, particularly combining bupropion/naltrexone and glucagon-like peptide 1 (GLP-1) analogue. The purpose of this study was to evaluate if there are any additive effects of prescribing bupropion/naltrexone on top of GLP-1 analogue as weight loss therapy.

METHODS

This was a retrospective cohort study of adult patients with a body mass index (BMI) ≥ 30 kg/m2 prescribed GLP-1 analogue therapy at an obesity specialist clinic in Vancouver, Canada. We compared a 6 and 12-month change in total body weight loss (TBWL) for those receiving monotherapy from the initiation of GLP-1 analogue therapy with those receiving combination therapy from the initiation of bupropion/naltrexone added-on therapy. Patients prescribed combination therapy were stratified into responder (loss of ≥ 5% TBWL) and non-responder (TBWL < 5%) subgroups based on initial response to the GLP-1 analogue alone for any amount of time.

RESULTS

The mean weight loss among patients prescribed GLP-1 analogue monotherapy at 12 months was 11.42 kg, SD 9.95 (9.6% TBWL). There was no significant difference between these two treatment strategies overall (HR 0.88, 95% CI 0.68 to 1.14, p = 0.35). However, when stratified by response to initial GLP analogue therapy, the addition of bupropion/naltrexone was associated with a statistically significant reduction in weight in both the responder (4.3% TBWL (p < 0.01)) and non-responder groups (4.0% TBWL (p < 0.01)).

CONCLUSIONS

GLP-1 analogues are an effective treatment for weight loss, and the addition of bupropion/naltrexone is associated with greater weight loss including in patients who are initially non-responsive to GLP-1 analogues.

Application of the Estimand Framework to Anesthesia Trials

SUMMARY

Events occurring after randomization, such as use of rescue medication, treatment discontinuation, or death, are common in randomized trials. These events can change either the existence or interpretation of the outcome of interest. However, appropriate handling of these intercurrent events is often unclear. The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) E9(R1) addendum introduced the estimand framework, which aligns trial objectives with the design, conduct, statistical analysis, and interpretation of results. This article describes how the estimand framework can be used in anesthesia trials to precisely define the treatment effect to be estimated, key attributes of an estimand, common intercurrent events in anesthesia trials with strategies for handling them, and use of the estimand framework in a hypothetical anesthesia trial on postoperative delirium. When planning anesthesia trials, clearly defining the estimand is vital to ensure that what is being estimated is clearly understood, is clinically relevant, and helps answer the clinical questions of interest.

Cost-effectiveness of weight-management pharmacotherapies in Canada: a societal perspective

OBJECTIVES

This study aimed to assess the cost-effectiveness of weight-management pharmacotherapies approved by Canada Health, i.e., orlistat, naltrexone 32 mg/bupropion 360 mg (NB-32), liraglutide 3.0 mg and semaglutide 2.4 mg as compared to the current standard of care (SoC).

METHODS

Analyses were conducted using a cohort with a mean starting age 50 years, body mass index (BMI) 37.5 kg/m2, and 27.6% having type 2 diabetes. Using treatment-specific changes in surrogate endpoints from the STEP trials (BMI, glycemic, blood pressure, lipids), besides a network meta-analysis, the occurrence of weight-related complications, costs, and quality-adjusted life-years (QALYs) were projected over lifetime.

RESULTS

From a societal perspective, at a willingness-to-pay (WTP) threshold of CAD 50 000 per QALY, semaglutide 2.4 mg was the most cost-effective treatment, at an incremental cost-utility ratio (ICUR) of CAD 31 243 and CAD 29 014 per QALY gained versus the next best alternative, i.e., orlistat, and SoC, respectively. Semaglutide 2.4 mg extendedly dominated other pharmacotherapies such as NB-32 or liraglutide 3.0 mg and remained cost-effective both under a public and private payer perspective. Results were robust to sensitivity analyses varying post-treatment catch-up rates, longer treatment durations and using real-world cohort characteristics. Semaglutide 2.4 mg was the preferred intervention, with a likelihood of 70% at a WTP threshold of CAD 50 000 per QALY gained. However, when the modeled benefits of weight-loss on cancer, mortality, cardiovascular disease (CVD) or osteoarthritis surgeries were removed simultaneously, orlistat emerged as the best value for money compared with SoC, with an ICUR of CAD 35 723 per QALY gained.

CONCLUSION

Semaglutide 2.4 mg was the most cost-effective treatment alternative compared with D&E or orlistat alone, and extendedly dominated other pharmacotherapies such as NB-32 or liraglutide 3.0 mg. Results were sensitive to the inclusion of the combined benefits of mortality, cancer, CVD, and knee osteoarthritis.

Efficacy and safety of once weekly semaglutide 2·4 mg for weight management in a predominantly east Asian population with overweight or obesity (STEP 7): a double-blind, multicentre, randomised controlled trial

BACKGROUND

Data on the benefits of the once weekly GLP-1 receptor agonist semaglutide 2·4 mg for weight management in people from east Asia are insufficient. The objective of this study was to determine the efficacy and safety of once weekly semaglutide 2·4 mg versus placebo for weight management in a predominantly east Asian adult population.

METHODS

This randomised phase 3a, double-blind multicentre controlled trial (STEP 7) recruited participants from 23 hospitals and trial centres in China, Hong Kong, Brazil, and South Korea. Adults with overweight or obesity, with or without type 2 diabetes, were randomly assigned (2:1) to receive a subcutaneous injection of either semaglutide 2·4 mg or placebo once a week for 44 weeks, plus a diet and physical activity intervention. Randomisation was done in blocks of six with an interactive web response system and was stratified by diagnosis of type 2 diabetes. Participants, investigators, and the trial sponsor were masked to treatment allocation until after database lock. Primary endpoints were percentage change in mean bodyweight and proportion of participants having reached a weight reduction of at least 5% of bodyweight from baseline to week 44. Safety was assessed in all participants who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT04251156, and is now complete.

FINDINGS

From Dec 8, 2020, to Aug 23, 2022, 448 participants were screened, of whom 375 were randomly assigned to either the semaglutide 2·4 mg group (n=249) or the placebo group (n=126). Estimated mean percentage change in bodyweight from baseline to week 44 was -12·1% (SE 0·5) with semaglutide 2·4 mg versus -3·6% (0·7) with placebo (estimated treatment difference -8·5 percentage points [95% CI -10·2 to -6·8]; p<0·0001). At week 44, the proportion of participants who lost 5% or more of their bodyweight was higher in the semaglutide 2·4 mg group than in the placebo group (203/238 [85%] vs 36/116 [31%]); odds ratio 13·1 (95% CI 7·4-23·1; p<0·0001). Adverse events were reported by 231 (93%) of 249 participants in the semaglutide 2·4 mg group and 108 (86%) of 126 participants in the placebo group, the most common of which were gastrointestinal disorders (168/249, 67% vs 45/126, 36%).

INTERPRETATION

The results of this study support the use of semaglutide 2·4 mg for weight management in people of east Asian ethnicity with overweight or obesity and with or without type 2 diabetes.

FUNDING

Novo Nordisk.

TRANSLATIONS

For the Mandarin, Portuguese and South Korean translations of the abstract see Supplementary Materials section.

Anti-obesity effect of Neoagaro-oligosaccharides with overweight and obese subjects: a 16-week, randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

This trial aimed to evaluate the anti-obesity effects and safety of Neoagaro-oligosaccharides (NAOs) in humans in a 16 week, randomized, double-blind, placebo-controlled clinical trial.

METHODS

One hundred overweight or obese subjects with a body mass index of 23 to 34.9 kg/m2 and a percent body fat of > 25% for males or > 30% for females were enrolled. NAOs or placebo products were administered at 3 g (twice a day, four capsules once) each for 16 weeks. Efficacy and safety biomarkers were measured before and after intervention.

RESULTS

After 16 weeks of intervention, the group administered with NAOs had statistically significant decreases in visceral fat area and visceral-subcutaneous fat area ratio compared to the placebo group. The NAOs group suppressed the increase in weight and BMI compared to the placebo group, which was significant between groups. High-density lipoprotein- cholesterol was increased in the group administered with NAOs, which showed a significant trend compared to the placebo group. Clinical changes were not observed for any safety biomarkers.

CONCLUSIONS

These results suggest that NAOs have a beneficial effect on obesity. Thus, NAOs could be used as an anti-obesity supplement without side effects.

TRIAL REGISTRATION

cris.nih.go.kr: (KCT0006640, 07/10/2021).

Oral semaglutide 50 mg taken once per day in adults with overweight or obesity (OASIS 1): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

We assessed the efficacy and safety of the oral glucagon-like peptide-1 analogue, semaglutide 50 mg, taken once per day versus placebo for the treatment of overweight or obesity in adults without type 2 diabetes.

METHODS

This randomised, double-blind, placebo-controlled, phase 3, superiority trial enrolled adults with a BMI of at least 30 kg/m2, or at least 27 kg/m2 with bodyweight-related complications and comorbidities, without type 2 diabetes. The trial was done at 50 outpatient clinics in nine countries across Asia, Europe, and North America. Participants were randomly allocated (1:1) via an interactive web-response system to oral semaglutide escalated to 50 mg, or visually matching placebo, once per day for 68 weeks, plus lifestyle intervention. Group assignment was masked for participants, investigators, and those assessing outcomes. Coprimary endpoints were the percentage change in bodyweight and whether participants reached a bodyweight reduction of at least 5% at week 68 for oral semaglutide 50 mg versus placebo, assessed regardless of treatment discontinuation or use of other bodyweight-lowering therapies (an intention-to-treat analysis). Safety was assessed in participants who received at least one dose of trial drug. This trial, registered with ClinicalTrials.gov (NCT05035095), is now complete.

FINDINGS

From Sept 13 to Nov 22, 2021, 709 participants were screened, of whom 667 were randomly assigned to oral semaglutide 50 mg (n=334) or placebo (n=333). The estimated mean bodyweight change from baseline to week 68 was -15·1% (SE 0·5) with oral semaglutide 50 mg versus -2·4% (0·5) with placebo (estimated treatment difference -12·7 percentage points, 95% CI -14·2 to -11·3; p<0·0001). More participants reached bodyweight reductions of at least 5% (269 [85%] of 317 vs 76 [26%] of 295; odds ratio [OR] 12·6, 95% CI 8·5 to 18·7; p<0·0001), 10% (220 [69%] vs 35 [12%]; OR 14·7, 9·6 to 22·6), 15% (170 [54%] vs 17 [6%]; OR 17·9, 10·4 to 30·7), and 20% (107 [34%] vs 8 [3%]; OR 18·5, 8·8 to 38·9) at week 68 with oral semaglutide 50 mg versus placebo. Adverse events were more frequent with oral semaglutide 50 mg (307 [92%] of 334) than with placebo (285 [86%] of 333). Gastrointestinal adverse events (mostly mild to moderate) were reported in 268 (80%) participants with oral semaglutide 50 mg and 154 (46%) with placebo.

INTERPRETATION

In adults with overweight or obesity without type 2 diabetes, oral semaglutide 50 mg once per day led to a superior and clinically meaningful decrease in bodyweight compared with placebo.

FUNDING

Novo Nordisk.

Treatment with GLP-1 receptor agonists is associated with significant weight loss and favorable headache outcomes in idiopathic intracranial hypertension

BACKGROUND

In idiopathic intracranial hypertension (IIH), sustained weight loss is the main pillar in modifying disease course, whereby glucagon-like peptide-1 receptor agonists (GLP-1-RAs) could present an attractive treatment option.

METHODS

In this open-label, single-center, case-control pilot study, patients with IIH (pwIIH) and a body mass index (BMI) of ≥ 30 kg/m² were offered to receive a GLP-1-RA (semaglutide, liraglutide) in addition to the usual care weight management (UCWM). Patients electing for UCWM only served as a control group matched for age-, sex- and BMI (1:2 ratio). The primary endpoint was the percentage weight loss at six months (M6) compared to baseline. Secondary endpoints included the rate of patients with a weight loss of ≥ 10%, monthly headache days (MHD), the rate of patients with a ≥ 30% and ≥ 50% reduction in MHD, visual outcome parameters, and adverse events (AEs).

RESULTS

We included 39 pwIIH (mean age 33.6 years [SD 8.0], 92.3% female, median BMI 36.3 kg/m² [IQR 31.4-38.3]), with 13 patients being treated with GLP-1-RAs. At M6, mean weight loss was significantly higher in the GLP-1-RA group (-12.0% [3.3] vs. -2.8% [4.7]; p < 0.001). Accordingly, weight loss of ≥ 10% was more common in this group (69.2% vs. 4.0%; p < 0.001). Median reduction in MHD was significantly higher in the GLP-1-RA group (-4 [-10.5, 0.5] vs. 0 [-3, 1]; p = 0.02), and the 50% responder rate was 76.9% vs. 40.0% (p = 0.04). Visual outcome parameters did not change significantly from baseline to M6. Median reduction in acetazolamide dosage was significantly higher in the GLP-1-RA group (-16.5% [-50, 0] vs. 0% [-25, 50]; p = 0.04). AEs were mild or moderate and attributed to gastrointestinal symptoms in 9/13 patients. None of the AEs led to premature treatment discontinuation.

CONCLUSIONS

This open-label, single-center pilot study suggests that GLP-1-RAs are an effective and safe treatment option for achieving significant weight loss with a favorable effect on headache, leading to reduced acetazolamide dosage in pwIIH.

Two-year effect of semaglutide 2.4 mg on control of eating in adults with overweight/obesity: STEP 5

OBJECTIVE

This study evaluated the effect of once-weekly semaglutide 2.4 mg on 2-year control of eating.

METHODS

In STEP 5, adults with overweight/obesity were randomized 1:1 to semaglutide 2.4 mg or placebo, plus lifestyle modification, for 104 weeks. A 19-item Control of Eating Questionnaire was administered at weeks 0, 20, 52, and 104 in a subgroup of participants. P values were not controlled for multiplicity.

RESULTS

In participants completing the Control of Eating Questionnaire (semaglutide, n = 88; placebo, n = 86), mean body weight changes were -14.8% (semaglutide) and -2.4% (placebo). Scores significantly improved with semaglutide versus placebo for Craving Control and Craving for Savory domains at weeks 20, 52, and 104 (p < 0.01); for Positive Mood and Craving for Sweet domains at weeks 20 and 52 (p < 0.05); and for hunger and fullness at week 20 (p < 0.001). Improvements in craving domain scores were positively correlated with reductions in body weight from baseline to week 104 with semaglutide. At 104 weeks, scores for desire to eat salty and spicy food, cravings for dairy and starchy foods, difficulty in resisting cravings, and control of eating were significantly reduced with semaglutide versus placebo (all p < 0.05).

CONCLUSIONS

In adults with overweight/obesity, semaglutide 2.4 mg improved short- and longer-term control of eating associated with substantial weight loss.

Semaglutide improves cardiometabolic risk factors in adults with overweight or obesity: STEP 1 and 4 exploratory analyses

AIMS

Evaluate the effects of once-weekly subcutaneous semaglutide 2.4 mg on cardiometabolic risk factors in people with overweight/obesity without diabetes in the STEP 1 and 4 trials.

MATERIALS AND METHODS

STEP 1 and 4 were phase III, 68-week, placebo-controlled trials of once-weekly semaglutide 2.4 mg combined with lifestyle intervention; STEP 4 had a 20-week semaglutide run-in and 48-week randomized withdrawal period. Participants had a body mass index ≥30 kg/m2 or ≥27 kg/m2 with one or more weight-related comorbidity, without diabetes. Pre-specified endpoints were changes in waist circumference, systolic/diastolic blood pressure (SBP/DBP), lipids, fasting plasma glucose (FPG), fasting serum insulin and antihypertensive/lipid-lowering medication use. Post-hoc assessments included non-high-density lipoprotein (HDL) cholesterol, homeostatic model assessment of insulin resistance (HOMA-IR; STEP 1 only), atherosclerotic cardiovascular disease (ASCVD) risk (American College of Cardiology/American Heart Association algorithm; STEP 1 only) and cardiometabolic risk factors by weight loss achieved (<5%, 5% to <10%, 10% to <15%, or ≥15%) (STEP 1 only).

RESULTS

Of the 1961 participants in STEP 1 and 803 in STEP 4, most had one or more complication/comorbidity at baseline, with dyslipidaemia and hypertension most prevalent. In STEP 1, reductions in waist circumference, SBP, DBP, FPG, fasting serum insulin, lipids and HOMA-IR were greater with semaglutide versus placebo (p ≤ .001). Reductions in SBP, non-HDL cholesterol, low-density lipoprotein cholesterol and FPG were generally greater with semaglutide than placebo within weight-loss categories. Non-significant ASCVD risk reductions were observed with semaglutide versus placebo (p > .05). In STEP 4, improvements in waist circumference, SBP, FPG, fasting serum insulin and lipids during the semaglutide run-in (week 0-20) were maintained over week 20-68 with continued semaglutide, but deteriorated following the switch to placebo (p < .001 [week 20-68]). Net reductions in antihypertensive/lipid-lowering medication use occurred with semaglutide versus placebo (both trials).

CONCLUSIONS

Semaglutide may improve cardiometabolic risk factors and reduce antihypertensive/lipid-lowering medication use versus placebo in adults with overweight/obesity without diabetes. These potential benefits were not maintained after treatment discontinuation.

CLINICALTRIALS

GOV NUMBERS

STEP 1 NCT03548935, STEP 4 NCT03548987.

Semaglutide for the treatment of overweight and obesity: A review

Obesity is a chronic, relapsing disease associated with multiple complications and a substantial morbidity, mortality and health care burden. Pharmacological treatments for obesity provide a valuable adjunct to lifestyle intervention, which often achieves only limited weight loss that is difficult to maintain. The Semaglutide Treatment Effect in People with obesity (STEP) clinical trial programme is evaluating once-weekly subcutaneous semaglutide 2.4 mg (a glucagon-like peptide-1 analogue) in people with overweight or obesity. Across STEP 1, 3, 4 and 8, semaglutide 2.4 mg was associated with mean weight losses of 14.9%-17.4% in individuals with overweight or obesity without type 2 diabetes from baseline to week 68; 69%-79% of participants achieved ≥10% weight loss with semaglutide 2.4 mg (vs. 12%-27% with placebo) and 51%-64% achieved ≥15% weight loss (vs. 5%-13% with placebo). In STEP 5, mean weight loss was -15.2% with semaglutide 2.4 mg versus -2.6% with placebo from baseline to week 104. In STEP 2 (individuals with overweight or obesity, and type 2 diabetes), mean weight loss was -9.6% with semaglutide 2.4 mg versus -3.4% with placebo from baseline to week 68. Improvements in cardiometabolic risk factors, including high blood pressure, atherogenic lipids and benefits on physical function and quality of life were seen with semaglutide 2.4 mg. The safety profile of semaglutide 2.4 mg was consistent across trials, primarily gastrointestinal adverse events. The magnitude of weight loss reported in the STEP trials offers the potential for clinically relevant improvement for individuals with obesity-related diseases.

Effects of once-weekly semaglutide 2.4 mg on C-reactive protein in adults with overweight or obesity (STEP 1, 2, and 3): Exploratory analyses of three randomised, double-blind, placebo-controlled, phase 3 trials

BACKGROUND

Inflammation is a key driver of atherosclerotic cardiovascular disease. C-reactive protein (CRP), an established biomarker of inflammation, is commonly elevated in people with overweight/obesity.

METHODS

STEP 1, 2, and 3 were 68-week, placebo-controlled trials of semaglutide for weight management in participants with overweight/obesity, with (STEP 2) or without (STEP 1 and 3) type 2 diabetes. Change in serum CRP from baseline to week 68 was assessed as a prespecified secondary endpoint for semaglutide 2.4 mg versus placebo (STEP 1, 2, and 3) and versus semaglutide 1.0 mg (STEP 2). Post hoc assessments included change in CRP by baseline characteristics (bodyweight, body mass index [BMI], glycaemic status, CRP concentration); change in CRP-defined cardiovascular risk category (<1 [low], 1-3 [intermediate], and >3 mg/L [high]); and correlation between change in CRP and change in bodyweight, waist circumference, fasting serum insulin (STEP 1 and 3), fasting plasma glucose, and homeostatic model assessment of insulin resistance (HOMA-IR).

FINDINGS

The trials took place from June through November 2018 (STEP 1 and 2) and from August 2018 to April 2020 (STEP 3). In all trials, semaglutide 2.4 mg reduced CRP at week 68 versus placebo (estimated treatment difference [ETD; 95% CI] -44% [-49 to -39] in STEP 1, -39% [-46 to -30] in STEP 2, and -48% [-55 to -39] in STEP 3; all p < 0.05). In STEP 2, CRP reductions were greater with semaglutide 2.4 mg (-49%) than with 1.0 mg (-42%) but the difference did not reach statistical significance (ETD [95% CI] -12% [-23 to 1]; p = 0.06). Reductions in CRP occurred in parallel with bodyweight loss and were consistent regardless of baseline BMI/bodyweight/glycaemic status. More semaglutide-treated participants had reductions in CRP-defined cardiovascular risk versus those on placebo. Reductions in CRP were positively correlated with reductions in bodyweight, waist circumference, fasting plasma glucose, fasting serum insulin, and HOMA-IR (data not shown).

INTERPRETATION

In people with overweight/obesity, once-weekly semaglutide 2.4 mg and 1.0 mg reduced CRP concentration irrespective of baseline BMI/bodyweight/glycaemic status compared with placebo. These data suggest a potential anti-inflammatory role of semaglutide in obesity.

FUNDING

Novo Nordisk.

Once-Weekly Semaglutide in Adolescents with Obesity

BACKGROUND

A once-weekly, 2.4-mg dose of subcutaneous semaglutide, a glucagon-like peptide-1 receptor agonist, is used to treat obesity in adults, but assessment of the drug in adolescents has been lacking.

METHODS

In this double-blind, parallel-group, randomized, placebo-controlled trial, we enrolled adolescents (12 to <18 years of age) with obesity (a body-mass index [BMI] in the 95th percentile or higher) or with overweight (a BMI in the 85th percentile or higher) and at least one weight-related coexisting condition. Participants were randomly assigned in a 2:1 ratio to receive once-weekly subcutaneous semaglutide (at a dose of 2.4 mg) or placebo for 68 weeks, plus lifestyle intervention. The primary end point was the percentage change in BMI from baseline to week 68; the secondary confirmatory end point was weight loss of at least 5% at week 68.

RESULTS

A total of 201 participants underwent randomization, and 180 (90%) completed treatment. All but one of the participants had obesity. The mean change in BMI from baseline to week 68 was -16.1% with semaglutide and 0.6% with placebo (estimated difference, -16.7 percentage points; 95% confidence interval [CI], -20.3 to -13.2; P<0.001). At week 68, a total of 95 of 131 participants (73%) in the semaglutide group had weight loss of 5% or more, as compared with 11 of 62 participants (18%) in the placebo group (estimated odds ratio, 14.0; 95% CI, 6.3 to 31.0; P<0.001). Reductions in body weight and improvement with respect to cardiometabolic risk factors (waist circumference and levels of glycated hemoglobin, lipids [except high-density lipoprotein cholesterol], and alanine aminotransferase) were greater with semaglutide than with placebo. The incidence of gastrointestinal adverse events was greater with semaglutide than with placebo (62% vs. 42%). Five participants (4%) in the semaglutide group and no participants in the placebo group had cholelithiasis. Serious adverse events were reported in 15 of 133 participants (11%) in the semaglutide group and in 6 of 67 participants (9%) in the placebo group.

CONCLUSIONS

Among adolescents with obesity, once-weekly treatment with a 2.4-mg dose of semaglutide plus lifestyle intervention resulted in a greater reduction in BMI than lifestyle intervention alone. (Funded by Novo Nordisk; STEP TEENS ClinicalTrials.gov number, NCT04102189.).

Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial

The STEP 5 trial assessed the efficacy and safety of once-weekly subcutaneous semaglutide 2.4 mg versus placebo (both plus behavioral intervention) for long-term treatment of adults with obesity, or overweight with at least one weight-related comorbidity, without diabetes. The co-primary endpoints were the percentage change in body weight and achievement of weight loss of ≥5% at week 104. Efficacy was assessed among all randomized participants regardless of treatment discontinuation or rescue intervention. From 5 October 2018 to 1 February 2019, 304 participants were randomly assigned to semaglutide 2.4 mg (n = 152) or placebo (n = 152), 92.8% of whom completed the trial (attended the end-of-trial safety visit). Most participants were female (236 (77.6%)) and white (283 (93.1%)), with a mean (s.d.) age of 47.3 (11.0) years, body mass index of 38.5 (6.9) kg m-2 and weight of 106.0 (22.0) kg. The mean change in body weight from baseline to week 104 was -15.2% in the semaglutide group (n = 152) versus -2.6% with placebo (n = 152), for an estimated treatment difference of -12.6 %-points (95% confidence interval, -15.3 to -9.8; P < 0.0001). More participants in the semaglutide group than in the placebo group achieved weight loss ≥5% from baseline at week 104 (77.1% versus 34.4%; P < 0.0001). Gastrointestinal adverse events, mostly mild-to-moderate, were reported more often with semaglutide than with placebo (82.2% versus 53.9%). In summary, in adults with overweight (with at least one weight-related comorbidity) or obesity, semaglutide treatment led to substantial, sustained weight loss over 104 weeks versus placebo. NCT03693430.

Changes in Glucose Metabolism and Glycemic Status With Once-Weekly Subcutaneous Semaglutide 2.4 mg Among Participants With Prediabetes in the STEP Program

OBJECTIVE

This analysis of 3,375 adults with overweight/obesity across the Semaglutide Treatment Effect in People with obesity (STEP) 1, 3, and 4 trials evaluated whether more participants with prediabetes had normoglycemia after 68 weeks' treatment with once-weekly semaglutide 2.4 mg plus lifestyle intervention versus placebo and assessed changes in glucose metabolism in participants with prediabetes.

RESEARCH DESIGN AND METHODS

STEP 1, 3, and 4 were phase 3, 68-week, randomized, placebo-controlled, multinational trials; STEP 4 had a 20-week semaglutide run-in and 48-week randomized period. Analyses included changes (week 0-68; before the washout period) in glycemic status (prespecified: STEP 1 and 3; post hoc: STEP 4), and in HbA1c, fasting plasma glucose (FPG), and HOMA insulin resistance (HOMA-IR) among participants with prediabetes (post hoc).

RESULTS

Significantly more participants with baseline (week 0) prediabetes (n = 1,536) had normoglycemia at week 68 with semaglutide versus placebo (STEP 1, 84.1% vs. 47.8%; STEP 3, 89.5% vs. 55.0%; STEP 4, 89.8% vs. 70.4%; all P < 0.0001). Fewer participants with baseline normoglycemia had prediabetes at week 68 with semaglutide versus placebo (STEP 1, 2.9% vs. 10.9%; STEP 3, 3.2% vs. 5.8%; STEP 4, 1.1% vs. 5.0%). Semaglutide resulted in greater improvements in HbA1c, FPG, and HOMA-IR than placebo among participants with baseline prediabetes (all P < 0.01).

CONCLUSIONS

STEP 1, 3, and 4 collectively provide a robust assessment of the effects of semaglutide on glucose metabolism and prediabetes in a large cohort of adults with overweight/obesity while on treatment. Among participants with baseline prediabetes, 68 weeks' treatment with semaglutide versus placebo led to significant improvements in glucose metabolism and a higher likelihood of normoglycemia.

Incorporating estimands into clinical trial statistical analysis plans

BACKGROUND

International Council for Harmonisation (ICH) E9 Statistical Principles for Clinical Trials was developed as a consensus guidance document to encourage worldwide harmonization of the principles of statistical methodology in clinical trials. Addendum E9 (R1) clarified and extended ICH E9 with a focus on estimands and sensitivity analyses. Since the release of E9 (R1), clinical trial protocols have included estimands, but there is variation in how they are presented. Statistical analysis plans (SAPs) are increasingly becoming publicly available (e.g. posting on ClinicalTrials.gov) and present an opportunity to link estimands with planned analyses to present the alignment of trial objectives, design, conduct, and analysis.

METHODS

A table format was used to create a template for inclusion in SAPs that satisfies ICH E9 (R1) guidance to align statistical analysis to the estimand. The template provides a consistent structure for presentation of estimands and the associated analysis, and is applicable to a wide range of trial designs. We illustrate use of the template with a hypothetical clinical trial in HIV-1.

RESULTS

The estimand-to-analysis table template starts with the study objective describing the clinical question of interest as written in the trial protocol. The remainder of the table describes each attribute of the estimand (treatment, target population, variable, intercurrent events, and population-level summary) in the left column (ESTIMAND), while the right column describes how each attribute will be handled using the data collected in the clinical trial (ANALYSIS). The template was applied to a hypothetical, early-phase single-arm trial, modeled after a pediatric trial in HIV, where the objective was to determine the safety of a new antiretroviral drug as part of a combination antiretroviral treatment regimen in the pediatric population. Three intercurrent events were illustrated in the table: death, premature treatment discontinuation before 24 weeks, and pregnancy. An estimand-to-analysis table from a grant application that addresses the primary objective of a placebo-controlled randomized trial is also presented to demonstrate an alternative usage.

CONCLUSION

We found the template to be useful in study design, providing a snapshot of the objective, target population, potential intercurrent events, analysis plan, and considerations for missing data in one place and facilitating discussion among stakeholders. The proposed standardized presentation of estimand attributes and analysis considerations in SAPs will provide guidance to SAP authors and consistency across studies to facilitate reviews.

Semaglutide once a week in adults with overweight or obesity, with or without type 2 diabetes in an east Asian population (STEP 6): a randomised, double-blind, double-dummy, placebo-controlled, phase 3a trial

BACKGROUND

Semaglutide 2·4 mg once weekly has been investigated for weight management in global populations. Differences exist between Asian and non-Asian populations in terms of body composition and definitions of obesity. In the Semaglutide Treatment Effect in People with obesity (STEP) 6 trial, we assessed the effect of semaglutide versus placebo for weight management in adults from east Asia with obesity, with or without type 2 diabetes.

METHODS

This randomised, double-blind, double-dummy, placebo-controlled, phase 3a superiority trial was done at 28 outpatient clinics in Japan and South Korea. Eligible participants were adults (aged ≥18 years in South Korea; ≥20 years in Japan) with a BMI of at least 27·0 kg/m² with two or more weight-related comorbidities or a BMI of 35·0 kg/m² or more with one or more weight-related comorbidity (one comorbidity had to be either hypertension, dyslipidaemia, or, in Japan only, type 2 diabetes) who had at least one self-reported unsuccessful dietary attempt to lose bodyweight. Participants were randomly assigned (4:1:2:1) to once-weekly subcutaneous semaglutide 2·4 mg or matching placebo, or semaglutide 1·7 mg or matching placebo, plus lifestyle recommendations for 68 weeks. Data for the placebo groups were pooled in statistical analyses. The primary endpoints were percentage change in bodyweight from baseline at week 68 and the proportion of participants who had achieved a reduction of at least 5% of baseline bodyweight at week 68. Change in abdominal visceral fat area was assessed as a supportive secondary endpoint using computed tomography scanning in a subset of participants. Efficacy outcomes were assessed in the full analysis set, which included all randomly assigned participants according to the intention-to-treat principle. Safety was assessed in all participants who received at least one dose of the study drug. This trial was registered with ClinicalTrials.gov, NCT03811574.

FINDINGS

Between Jan 21, 2019 and June 4, 2019, 437 participants were screened, of whom 401 were randomly assigned to semaglutide 2·4 mg (n=199), semaglutide 1·7 mg (n=101), or placebo (n=101) and included in the intention-to-treat analysis. Estimated mean change in bodyweight from baseline to week 68 was -13·2% (SEM 0·5) in the semaglutide 2·4 mg group and -9·6% (0·8) in the semaglutide 1·7 mg group versus -2·1% (0·8) in the placebo group (estimated treatment difference [ETD] -11·1 percentage points [95% CI -12·9 to -9·2] for semaglutide 2·4 mg vs placebo; -7·5 percentage points [95% CI -9·6 to -5·4] for semaglutide 1·7 mg vs placebo; both p<0·0001). At week 68, a larger proportion of participants had achieved a 5% or higher reduction in baseline bodyweight in the semaglutide 2·4 mg group (160 [83%] of 193 participants) and semaglutide 1·7 mg group (71 [72%] of 98 participants) than in the placebo group (21 [21%] of 100 participants); odds ratio [OR] 21·7 [95% CI 11·3 to 41·9] for semaglutide 2·4 mg vs placebo; OR 11·1 [95% CI 5·5 to 22·2] for semaglutide 1·7 mg vs placebo; both p<0·0001). Abdominal visceral fat area was reduced by 40·0% (SEM 2·6) among participants in the semaglutide 2·4 mg group and 22·2% (3·7) among participants in the semaglutide 1·7 mg group versus 6·9% (3·8) in the placebo group (ETD -33·2% [95% CI -42·1 to -24·2] for semaglutide 2·4 mg vs placebo; -15·3% [95% CI -25·6 to -4·9] for semaglutide 1·7 mg vs placebo). 171 (86%) of 199 participants in the semaglutide 2·4 mg group, 82 (82%) of 100 participants in the semaglutide 1·7 mg group, and 80 (79%) of 101 participants in the placebo group reported adverse events. Gastrointestinal disorders, which were mostly mild to moderate, were reported in 118 (59%) of 199 participants in the semaglutide 2·4 mg group, 64 (64%) of 100 participants in the semaglutide 1·7 mg group, and 30 (30%) of 101 participants in the placebo group. Adverse events leading to trial product discontinuation occurred in five (3%) of 199 participants in the semaglutide 2·4 mg group, three (3%) of 100 participants in the semaglutide 1·7 mg group, and one (1%) of 101 participants in the placebo group.

INTERPRETATION

Adults from east Asia with obesity, with or without type 2 diabetes, given semaglutide 2·4 mg once a week had superior and clinically meaningful reductions in bodyweight, and greater reductions in abdominal visceral fat area compared with placebo, representing a promising treatment option for weight management in this population.

FUNDING

Novo Nordisk.

TRANSLATIONS

For the Korean and Japanese translations of the abstract see Supplementary Materials section.

Effect of Weekly Subcutaneous Semaglutide vs Daily Liraglutide on Body Weight in Adults With Overweight or Obesity Without Diabetes: The STEP 8 Randomized Clinical Trial

IMPORTANCE

Phase 3 trials have not compared semaglutide and liraglutide, glucagon-like peptide-1 analogues available for weight management.

OBJECTIVE

To compare the efficacy and adverse event profiles of once-weekly subcutaneous semaglutide, 2.4 mg, vs once-daily subcutaneous liraglutide, 3.0 mg (both with diet and physical activity), in people with overweight or obesity.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, open-label, 68-week, phase 3b trial conducted at 19 US sites from September 2019 (enrollment: September 11-November 26) to May 2021 (end of follow-up: May 11) in adults with body mass index of 30 or greater or 27 or greater with 1 or more weight-related comorbidities, without diabetes (N = 338).

INTERVENTIONS

Participants were randomized (3:1:3:1) to receive once-weekly subcutaneous semaglutide, 2.4 mg (16-week escalation; n = 126), or matching placebo, or once-daily subcutaneous liraglutide, 3.0 mg (4-week escalation; n = 127), or matching placebo, plus diet and physical activity. Participants unable to tolerate 2.4 mg of semaglutide could receive 1.7 mg; participants unable to tolerate 3.0 mg of liraglutide discontinued treatment and could restart the 4-week titration. Placebo groups were pooled (n = 85).

MAIN OUTCOMES AND MEASURES

The primary end point was percentage change in body weight, and confirmatory secondary end points were achievement of 10% or more, 15% or more, and 20% or more weight loss, assessed for semaglutide vs liraglutide at week 68. Semaglutide vs liraglutide comparisons were open-label, with active treatment groups double-blinded against matched placebo groups. Comparisons of active treatments vs pooled placebo were supportive secondary end points.

RESULTS

Of 338 randomized participants (mean [SD] age, 49 [13] years; 265 women [78.4%]; mean [SD] body weight, 104.5 [23.8] kg; mean [SD] body mass index, 37.5 [6.8]), 319 (94.4%) completed the trial, and 271 (80.2%) completed treatment. The mean weight change from baseline was -15.8% with semaglutide vs -6.4% with liraglutide (difference, -9.4 percentage points [95% CI, -12.0 to -6.8]; P < .001); weight change with pooled placebo was -1.9%. Participants had significantly greater odds of achieving 10% or more, 15% or more, and 20% or more weight loss with semaglutide vs liraglutide (70.9% of participants vs 25.6% [odds ratio, 6.3 {95% CI, 3.5 to 11.2}], 55.6% vs 12.0% [odds ratio, 7.9 {95% CI, 4.1 to 15.4}], and 38.5% vs 6.0% [odds ratio, 8.2 {95% CI, 3.5 to 19.1}], respectively; all P < .001). Proportions of participants discontinuing treatment for any reason were 13.5% with semaglutide and 27.6% with liraglutide. Gastrointestinal adverse events were reported by 84.1% with semaglutide and 82.7% with liraglutide.

CONCLUSIONS AND RELEVANCE

Among adults with overweight or obesity without diabetes, once-weekly subcutaneous semaglutide compared with once-daily subcutaneous liraglutide, added to counseling for diet and physical activity, resulted in significantly greater weight loss at 68 weeks.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04074161.

Efficacy and safety of semaglutide for weight management: evidence from the STEP program

Obesity is a global health challenge. It is a multifactorial, complex, and progressive disease associated with various health complications and increased mortality. Lifestyle modifications are central to weight management but may be insufficient to maintain clinically meaningful weight loss. Pharmacotherapies are recommended as an adjunct to lifestyle interventions to induce and sustain clinically meaningful weight loss and reduce the risk of comorbidities in appropriate patients. Glucagon-like peptide-1 is an incretin metabolic hormone responsible for a range of physiological effects, including glucose and appetite regulation. Several glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been approved for the treatment of type 2 diabetes since 2005 including exenatide (short- and extended-release), lixisenatide, liraglutide, dulaglutide, albiglutide, and semaglutide. Of these, semaglutide (subcutaneous) and liraglutide are currently US Food and Drug Administration (FDA)-approved for chronic weight management in patients with or without diabetes. The phase 3 Semaglutide Treatment Effect in People with obesity (STEP) program was designed to investigate the effect of semaglutide versus placebo on weight loss, safety, and tolerability in adults with overweight or obesity. Following the submission of the results of the STEP 1-4 trials, the FDA approved once-weekly subcutaneous semaglutide 2.4 mg for chronic weight management in people with overweight or obesity in April 2021. Data from the program demonstrated that semaglutide (2.4 mg once weekly) achieved significant and sustained weight loss, together with improvements in cardiometabolic risk factors compared with placebo, and was generally well tolerated, with a safety profile consistent with other GLP-1RAs. The most common adverse events reported in STEP 1-5 were gastrointestinal events, which were transient, mild-to-moderate in severity, and typically resolved without permanent treatment discontinuation. This article reviews the data from STEP 1-5 and highlights clinically relevant findings for primary care providers.

Semaglutide 2.4 Mg for the Management of Overweight and Obesity: Systematic Literature Review and Meta-Analysis

PURPOSE

Semaglutide has demonstrated safe and effective weight loss for overweight and obesity, including participants with concomitant type 2 diabetes mellitus (T2DM), in randomized placebo-controlled trials (RCTs). We conducted a systematic literature review (SLR) and network meta-analyses (NMA) to compare weekly semaglutide 2.4 mg with pharmacological comparators for weight management in overweight or obesity.

METHODS

The SLR was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. NMAs were performed to compare weight change for semaglutide 2.4 mg with comparators using data identified in the SLR. The populations of interest were total population, normal glucose tolerance, non-T2DM, pre-diabetes, and T2DM. Included outcomes were weight change from baseline (CFB, %) at 52 weeks and proportion of participants losing ≥5% baseline fasting body weight at 12 weeks (at full therapeutic dose).

RESULTS

The SLR identified 108 RCTs examining non-surgical interventions, of which 41 were considered for inclusion in the NMAs. In all populations, semaglutide 2.4 mg was associated with a greater percentage weight CFB with 52 weeks of treatment versus all available comparators. In all populations, semaglutide was associated with a higher likelihood of participants losing ≥5% of baseline fasting body weight at 12 weeks versus all available comparators.

CONCLUSION

In NMA, semaglutide 2.4 mg demonstrated effective weight loss (≥5%) in the total population and all subpopulations of glucose tolerance versus active comparators. Semaglutide is an effective treatment that may address unmet need in the management of overweight and obesity.

Gastrointestinal tolerability of once-weekly semaglutide 2.4 mg in adults with overweight or obesity, and the relationship between gastrointestinal adverse events and weight loss

AIM

We evaluated gastrointestinal (GI) adverse events (AEs) with once-weekly semaglutide 2.4 mg in adults with overweight or obesity and their contribution to weight loss (WL).

MATERIALS AND METHODS

AE analyses pooled data from the Semaglutide Treatment Effect in People With Obesity (STEP) 1-3 trials for participants randomized to 68 weeks of semaglutide 2.4 mg (n = 2117) or placebo (n = 1262). WL was analysed by presence/absence of GI AEs. Mediation analysis estimated WL effects mediated by and unrelated to GI AEs. GI tolerability with semaglutide 2.4 mg maintenance and cessation after dose escalation was evaluated using STEP 4 data among 803 participants tolerating 20 weeks of semaglutide run-in.

RESULTS

GI AEs were more common with semaglutide 2.4 mg than placebo, with most frequently nausea (43.9% vs. 16.1% of participants), diarrhoea (29.7% vs. 15.9%), vomiting (24.5% vs. 6.3%) and constipation (24.2% vs. 11.1%). Most GI AEs with semaglutide were non-serious (99.5% of AEs), mild-to-moderate (98.1%), transient and occurred most frequently during/shortly after dose escalation. Few semaglutide-treated participants (4.3%) permanently discontinued treatment for GI AEs. In STEP 1-3, mean WL with semaglutide 2.4 mg was similar in participants without (9.6%-17.1%) versus with GI AEs (11.4%-17.7%). Consistent with this observation, mediation analysis found that GI AEs contributed little to semaglutide-induced WL: of the additional 7.6%-14.4% WL with semaglutide versus placebo, <1 percentage point was mediated by GI AEs. In STEP 4, semaglutide 2.4 mg maintenance was well tolerated.

CONCLUSIONS

GI AEs were more common with semaglutide 2.4 mg than placebo, but typically mild-to-moderate and transient. Semaglutide-induced WL was largely independent of GI AEs.

Estimands-a Basic Element for Clinical Trials. Part 29 of a Series on Evaluation of Scientific Publications

BACKGROUND

Clinical trials are of central importance for the evaluation and comparison of treatments. The transparency and intelligibility of the treatment effect under investigation is an essential matter for physicians, patients, and health-care authorities. The estimand framework has been introduced because many trials are deficient in this respect.

METHODS

Introduction, definition, and application of the estimand framework on the basis of an example and a selective review of the literature.

RESULTS

The estimand framework provides a systematic approach to the definition of the treatment effect under investigation in a clinical trial. An estimand consists of five attributes: treatment, population, variable, population-level summary, and handling of intercurrent events. Each of these attributes is defined in an interdisciplinary discussion during the trial planning phase, based on the clinical question being asked. Special attention is given to the handling of intercurrent events (ICEs): these are events-e.g., discontinuation or modification of treatment or the use of emergency medication-that can occur once the treatment has begun and might affect the possibility of observing the endpoints or their interpretability. There are various strategies for the handling of ICEs; these can, for example, also reflect the existing intentionto- treat (ITT) principle. Per-protocol analyses, in contrast, are prone to bias and cannot be represented in a sensible manner by an estimand, although they may be performed as a supplementary analysis. The discussion of potential intercurrent events and how they should appropriately be handled in view of the aim of the trial must already take place in the planning phase.

CONCLUSION

Use of the estimand framework should make it easier for both physicians and patients to understand what trials reveal about the efficacy of treatment, and to compare the results of different trials.

Once-weekly cagrilintide for weight management in people with overweight and obesity: a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial

BACKGROUND

Natural amylin is a pancreatic hormone that induces satiety. Cagrilintide is a long-acting amylin analogue under investigation for weight management. We assessed the dose-response relationship of cagrilintide regarding the effects on bodyweight, safety, and tolerability.

METHODS

We conducted a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial at 57 sites including hospitals, specialist clinics, and primary care centres in ten countries (Canada, Denmark, Finland, Ireland, Japan, Poland, Serbia, South Africa, the UK, and the USA). Eligible participants were adults aged at least 18 years without diabetes, with a body-mass index of at least 30 kg/m² or at least 27 kg/m² with hypertension or dyslipidaemia. Participants were randomly assigned (6:1) to subcutaneous self-injections of once-weekly cagrilintide (0·3, 0·6, 1·2, 2·4, or 4·5 mg), once-daily liraglutide 3·0 mg, or volume-matched placebo (for six placebo groups). The trial had a 26-week treatment period, including a dose-escalation period of up to 6 weeks, and a 6-week follow-up period without treatment. Participants and investigators were masked to the assigned study treatment with respect to active versus pooled placebo treatment, but not to different active treatments. The primary endpoint was the percentage change in bodyweight from baseline to week 26, assessed in all randomly assigned participants according to the trial product estimand (assuming all participants were adherent to treatment) and to the treatment policy estimand (regardless of adherence to treatment). Safety was assessed in all participants who received at least one dose of randomised treatment. This trial is registered with ClinicalTrials.gov, NCT03856047, and is closed to new participants.

FINDINGS

Between March 1 and Aug 19, 2019, we randomly assigned 706 participants to cagrilintide 0·3-4·5 mg (100-102 per dose group), 99 to liraglutide 3·0 mg, and 101 to placebo. Permanent treatment discontinuation (n=73 [10%]) occurred similarly across treatment groups, mostly due to adverse events (n=30 [4%]). In total, 29 participants (4%) withdrew from the trial. According to the trial product estimand, mean percentage weight reductions from baseline were greater with all doses of cagrilintide (0·3-4·5 mg, 6·0%-10·8% [6·4-11·5 kg]) versus placebo (3·0% [3·3 kg]; estimated treatment difference range 3·0%-7·8%; p<0·001). Weight reductions were also greater with cagrilintide 4·5 mg versus liraglutide 3·0 mg (10·8% [11·5 kg] vs 9·0% [9·6 kg]; estimated treatment difference 1·8%, p=0·03). Similar weight loss reductions were observed with the treatment policy estimand. The most frequent adverse events were gastrointestinal disorders (eg, nausea, constipation, and diarrhoea) and administration-site reactions. More participants receiving cagrilintide 0·3-4·5 mg had gastrointestinal adverse events compared with placebo (41%-63% vs 32%), primarily nausea (20%-47% vs 18%).

INTERPRETATION

Treatment with cagrilintide in people with overweight and obesity led to significant reductions in bodyweight and was well tolerated. The findings support the development of molecules with novel mechanisms of action for weight management.

FUNDING

Novo Nordisk A/S.

Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight in Adults With Overweight or Obesity: The STEP 3 Randomized Clinical Trial

Importance

Weight loss improves cardiometabolic risk factors in people with overweight or obesity. Intensive lifestyle intervention and pharmacotherapy are the most effective noninvasive weight loss approaches.

Objective

To compare the effects of once-weekly subcutaneous semaglutide, 2.4 mg vs placebo for weight management as an adjunct to intensive behavioral therapy with initial low-calorie diet in adults with overweight or obesity.

Design, Setting, and Participants

Randomized, double-blind, parallel-group, 68-week, phase 3a study (STEP 3) conducted at 41 sites in the US from August 2018 to April 2020 in adults without diabetes (N = 611) and with either overweight (body mass index ≥27) plus at least 1 comorbidity or obesity (body mass index ≥30).

Interventions

Participants were randomized (2:1) to semaglutide, 2.4 mg (n = 407) or placebo (n = 204), both combined with a low-calorie diet for the first 8 weeks and intensive behavioral therapy (ie, 30 counseling visits) during 68 weeks.

Main Outcomes and Measures

The co-primary end points were percentage change in body weight and the loss of 5% or more of baseline weight by week 68. Confirmatory secondary end points included losses of at least 10% or 15% of baseline weight.

Results

Of 611 randomized participants (495 women [81.0%], mean age 46 years [SD, 13], body weight 105.8 kg [SD, 22.9], and body mass index 38.0 [SD, 6.7]), 567 (92.8%) completed the trial, and 505 (82.7%) were receiving treatment at trial end. At week 68, the estimated mean body weight change from baseline was -16.0% for semaglutide vs -5.7% for placebo (difference, -10.3 percentage points [95% CI, -12.0 to -8.6]; P < .001). More participants treated with semaglutide vs placebo lost at least 5% of baseline body weight (86.6% vs 47.6%, respectively; P < .001). A higher proportion of participants in the semaglutide vs placebo group achieved weight losses of at least 10% or 15% (75.3% vs 27.0% and 55.8% vs 13.2%, respectively; P < .001). Gastrointestinal adverse events were more frequent with semaglutide (82.8%) vs placebo (63.2%). Treatment was discontinued owing to these events in 3.4% of semaglutide participants vs 0% of placebo participants.

Conclusions and Relevance

Among adults with overweight or obesity, once-weekly subcutaneous semaglutide compared with placebo, used as an adjunct to intensive behavioral therapy and initial low-calorie diet, resulted in significantly greater weight loss during 68 weeks. Further research is needed to assess the durability of these findings.

Trial Registration

ClinicalTrials.gov Identifier: NCT03611582.

Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance in Adults With Overweight or Obesity: The STEP 4 Randomized Clinical Trial

IMPORTANCE

The effect of continuing vs withdrawing treatment with semaglutide, a glucagon-like peptide 1 receptor agonist, on weight loss maintenance in people with overweight or obesity is unknown.

OBJECTIVE

To compare continued once-weekly treatment with subcutaneous semaglutide, 2.4 mg, with switch to placebo for weight maintenance (both with lifestyle intervention) in adults with overweight or obesity after a 20-week run-in with subcutaneous semaglutide titrated to 2.4 mg weekly.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, 68-week phase 3a withdrawal study conducted at 73 sites in 10 countries from June 2018 to March 2020 in adults with body mass index of at least 30 (or ≥27 with ≥1 weight-related comorbidity) and without diabetes.

INTERVENTIONS

A total of 902 participants received once-weekly subcutaneous semaglutide during run-in. After 20 weeks (16 weeks of dose escalation; 4 weeks of maintenance dose), 803 participants (89.0%) who reached the 2.4-mg/wk semaglutide maintenance dose were randomized (2:1) to 48 weeks of continued subcutaneous semaglutide (n = 535) or switched to placebo (n = 268), plus lifestyle intervention in both groups.

MAIN OUTCOMES AND MEASURES

The primary end point was percent change in body weight from week 20 to week 68; confirmatory secondary end points were changes in waist circumference, systolic blood pressure, and physical functioning (assessed using the Short Form 36 Version 2 Health Survey, Acute Version [SF-36]).

RESULTS

Among 803 study participants who completed the 20-week run-in period (with a mean weight loss of 10.6%) and were randomized (mean age, 46 [SD, 12] years; 634 [79%] women; mean body weight, 107.2 kg [SD, 22.7 kg]), 787 participants (98.0%) completed the trial and 741 (92.3%) completed treatment. With continued semaglutide, mean body weight change from week 20 to week 68 was -7.9% vs +6.9% with the switch to placebo (difference, -14.8 [95% CI, -16.0 to -13.5] percentage points; P < .001). Waist circumference (-9.7 cm [95% CI, -10.9 to -8.5 cm]), systolic blood pressure (-3.9 mm Hg [95% CI, -5.8 to -2.0 mm Hg]), and SF-36 physical functioning score (2.5 [95% CI, 1.6-3.3]) also improved with continued subcutaneous semaglutide vs placebo (all P < .001). Gastrointestinal events were reported in 49.1% of participants who continued subcutaneous semaglutide vs 26.1% with placebo; similar proportions discontinued treatment because of adverse events with continued semaglutide (2.4%) and placebo (2.2%).

CONCLUSIONS AND RELEVANCE

Among adults with overweight or obesity who completed a 20-week run-in period with subcutaneous semaglutide, 2.4 mg once weekly, maintaining treatment with semaglutide compared with switching to placebo resulted in continued weight loss over the following 48 weeks.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03548987.

Semaglutide 2·4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial

BACKGROUND

This trial assessed the efficacy and safety of the GLP-1 analogue once a week subcutaneous semaglutide 2·4 mg versus semaglutide 1·0 mg (the dose approved for diabetes treatment) and placebo for weight management in adults with overweight or obesity, and type 2 diabetes.

METHODS

This double-blind, double-dummy, phase 3, superiority study enrolled adults with a body-mass index of at least 27 kg/m² and glycated haemoglobin 7-10% (53-86 mmol/mol) who had been diagnosed with type 2 diabetes at least 180 days before screening. Patients were recruited from 149 outpatient clinics in 12 countries across Europe, North America, South America, the Middle East, South Africa, and Asia. Patients were randomly allocated (1:1:1) via an interactive web-response system and stratified by background glucose-lowering medication and glycated haemoglobin, to subcutaneous injection of semaglutide 2·4 mg, or semaglutide 1·0 mg, or visually matching placebo, once a week for 68 weeks, plus a lifestyle intervention. Patients, investigators, and those assessing outcomes were masked to group assignment. Coprimary endpoints were percentage change in bodyweight and achievement of weight reduction of at least 5% at 68 weeks for semaglutide 2·4 mg versus placebo, assessed by intention to treat. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT03552757 and is closed to new participants.

FINDINGS

From June 4 to Nov 14, 2018, 1595 patients were screened, of whom 1210 were randomly assigned to semaglutide 2·4 mg (n=404), semaglutide 1·0 mg (n=403), or placebo (n=403) and included in the intention-to-treat analysis. Estimated change in mean bodyweight from baseline to week 68 was -9·6% (SE 0·4) with semaglutide 2·4 mg vs -3·4% (0·4) with placebo. Estimated treatment difference for semaglutide 2·4 mg versus placebo was -6·2 percentage points (95% CI -7·3 to -5·2; p<0·0001). At week 68, more patients on semaglutide 2·4 mg than on placebo achieved weight reductions of at least 5% (267 [68·8%] of 388 vs 107 [28·5%] of 376; odds ratio 4·88, 95% CI 3·58 to 6·64; p<0·0001). Adverse events were more frequent with semaglutide 2·4 mg (in 353 [87·6%] of 403 patients) and 1·0 mg (329 [81·8%] of 402) than with placebo (309 [76·9%] of 402). Gastrointestinal adverse events, which were mostly mild to moderate, were reported in 256 (63·5%) of 403 patients with semaglutide 2·4 mg, 231 (57·5%) of 402 with semaglutide 1·0 mg, and 138 (34·3%) of 402 with placebo.

INTERPRETATION

In adults with overweight or obesity, and type 2 diabetes, semaglutide 2·4 mg once a week achieved a superior and clinically meaningful decrease in bodyweight compared with placebo.

FUNDING

Novo Nordisk.