Retrospective Comparative Study of Oral Versus Subcutaneous Semaglutide in Patients with Type 2 Diabetes Mellitus
Abstract
1. Introduction
2. Results
2.1. Population Characteristics
2.2. 18-Month Effects of Oral vs. Subcutaneous Semaglutide on Metabolic Parameters and Cardiovascular Risk Factors
2.3. Impact of the Route of Semaglutide Administration on Metabolic Parameters and Cardiovascular Risk Factors: Multivariate Analysis
2.4. Oral vs. Subcutaneous Semaglutide on Metabolic Parameters After Propensity Score Matching
3. Discussion
4. Materials and Methods
4.1. Study Design
4.2. Statistical Analysis
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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| Variable | All Patients (n = 434) | Oral GLP-1RA (n = 232) | scGLP-1RA (n = 202) | p-Value | |
|---|---|---|---|---|---|
| Age (years) | 70 (63–76) | 71 (63.7–77.2) | 69 (62–75) | 0.07 | |
| Sex (n; %) | M | 247/434 (56.9%) | 132/232 (56.9%) | 115/202 (56.9%) | 0.99 |
| F | 187/434 (43.1%) | 100/232 (43.1%) | 87/202 (43.1%) | ||
| Diabetes duration (years) | 13 (7–22) | 12 (6–21) | 15 (8–22) | 0.028 | |
| Baseline HbA1c (%) | 7.4 (6.7–8.1) | 7.3 (6.6–8.1) | 7.5 (6.8–8.1) | 0.253 | |
| Baseline BMI (kg/m2) | 30.9 (27.4–35.5) | 29.1 (26.3–33.6) | 33.4 (29.5–37.6) | <0.0001 | |
| Dose of oral semaglutide (mg) | 3 mg | 25/232 (10.8%) | 25/232 (10.8%) | NA | |
| 7 mg | 90/232 (38.8%) | 90/232 (38.8%) | |||
| 14 mg | 117/232 (50.4%) | 117/232 (50.4%) | |||
| Dose of sc semaglutide (mg) | 0.5 mg | 166/202 (32.7%) | NA | 166/202 (32.7%) | |
| 1 mg | 136/202 (67.3%) | 136/202 (67.3%) | |||
| Monotherapy (Yes) (n; %) | 32/434 (7.4%) | 20/232 (8.6%) | 12/202 (5.9%) | 0.286 | |
| Semaglutide (n; %) | SWITCH | 292/434 (67.3%) | 157/232 (67.7%) | 135/202 (66.8%) | 0.852 |
| ADD-ON | 142/434 (32.7%) | 75/232 (32.3%) | 67/202 (33.2%) | ||
| Metformin (Yes) (n; %) | 306/434 (70.5%) | 148/232 (63.8%) | 158/202 (78.2%) | 0.001 | |
| SGLT2i (Yes) (n; %) | 151/434 (34.8%) | 118/232 (50.9%) | 33/202 (16.3%) | <0.0001 | |
| Insulin (Yes) (n; %) | 143/434 (32.9%) | 78/232 (33.6%) | 65/202 (32.2%) | 0.750 | |
| SU (Yes) (n; %) | 70/434 (16.1%) | 24/232 (10.3%) | 46/202 (22.8%) | 0.001 | |
| Pioglitazone (Yes) (n; %) | 35/434 (8.1%) | 16/232 (6.9%) | 19/202 (9.4%) | 0.338 | |
| Treatment discontinuation (Yes) (n; %) | 73/434 (16.8%) | 60/232 (25.9%) | 13/202 (6.4%) | <0.0001 | |
| Reasons for discontinuation (n, %) | GI adverse events | 21/73 (28.8%) | 18/60 (30.0%) | 3/13 (23.1%) | 0.009 |
| Other adverse events | 24/73 (32.9%) | 20/60 (33.3%) | 4/13 (30.8%) | ||
| Lack of efficacy | 4/73 (5.5%) | 4/60 (6.7%) | 0/13 (0.0%) | ||
| Treatment change | 11/73 (15.1%) | 7/60 (11.7%) | 4/13 (30.7%) | ||
| Injection site reactions | 2/73 (2.7%) | 0/60 (0.0%) | 2/13 (15.4%) | ||
| ND | 11/73 (15.1%) | 11/60 (18.3%) | 0/13 (0.0%) |
| Variable | Oral GLP-1RA (n = 130) | scGLP-1RA (n = 145) | p-Value | |
|---|---|---|---|---|
| Age (years) | 71 (65–77) | 69 (62–75) | 0.131 | |
| Sex (n; %) | M | 79/130 (60.8%) | 81/145 (55.9%) | 0.41 |
| F | 51/130 (39.2%) | 64/145 (44.1%) | ||
| Diabetes duration (years) | 12 (7–21) | 15 (9–23) | 0.013 | |
| Baseline HbA1c (%) | 7.4 (6.8–8.2) | 7.5 (6.9–8.2) | 0.633 | |
| Baseline BMI (kg/m2) | 29.1 (26.2–33.0) | 33.6 (29.8–37.9) | <0.0001 | |
| Dose of oral semaglutide (mg) | 3 mg | 5/130 (3.9%) | NA | |
| 7 mg | 34/130 (26.1%) | |||
| 14 mg | 91/130 (70.0%) | |||
| Dose of subcutaneous semaglutide (mg) | 0.5 mg | NA | 37/145 (25.5%) | |
| 1 mg | 108/145 (74.5%) | |||
| Monotherapy (Yes) (n; %) | 8/130 (6.2%) | 7/145 (4.8%) | 0.629 | |
| Semaglutide (n; %) | SWITCH | 91/130 (70.0%) | 100/145 (69.0%) | 0.852 |
| ADD-ON | 39/130 (30.0%) | 45/145 (31.0%) | ||
| Metformin (Yes) (n; %) | 84/130 (64.6%) | 110/145 (75.9%) | 0.041 | |
| SGLT2i (Yes) (n; %) | 72/130 (55.4%) | 27/145 (18.6%) | <0.0001 | |
| Insulin (Yes) (n; %) | 43/130 (33.1%) | 51/145 (35.2%) | 0.714 | |
| SU (Yes) (n; %) | 18/130 (13.8%) | 39/145 (26.9%) | 0.008 | |
| Pioglitazone (Yes) (n; %) | 10/130 (7.7%) | 13/145 (9.0%) | 0.703 | |
| Treatment discontinuation (Yes) (n; %) | 12/130 (9.2%) | 8/145 (5.5%) | 0.236 |
| Predictive Variable | HbA1c Change | ||
|---|---|---|---|
| β-estimate | 95% CI | p-value | |
| Age | 0.010 | [−0.002;0.021] | 0.091 |
| Sex (Male) | −0.142 | [−0.358;0.074] | 0.197 |
| scGLP-1RA (vs. oral GLP-1RA) | 0.105 | [−0.134; 0.344] | 0.388 |
| Baseline BMI | −0.029 | [−0.048; −0.010] | 0.004 |
| Baseline HbA1c | −0.741 | [−0.818; −0.664] | <0.0001 |
| SGLT2i (yes vs. no) | 0.244 | [0.008; 0.480] | 0.043 |
| Sulphonylureas (yes vs. no) | 0.208 | [−0.067; 0.483] | 0.138 |
| Predictive Variable | BMI Change | ||
| β-estimate | 95% CI | p-value | |
| Age | 0.006 | [−0.026; 0.038] | 0.724 |
| Sex (Male) | 0.722 | [0.108; 1.336] | 0.021 |
| scGLP-1RA (vs. oral GLP-1RA) | −0.440 | [−1.116; 0.235] | 0.200 |
| Baseline BMI | −0.134 | [−0.191; −0.077] | <0.0001 |
| Baseline HbA1c | −0.040 | [−0.253; 0.174] | 0.714 |
| SGLT2i (yes vs. no) | −0.561 | [−1.219; 0.096] | 0.094 |
| Predictive Variable | SBP Change | ||
|---|---|---|---|
| β-estimate | 95% CI | p-value | |
| Age | 0.135 | [−0.068; 0.337] | 0.191 |
| Sex (Male) | −1.291 | [−5.289; 2.707] | 0.524 |
| scGLP-1RA (vs. oral GLP-1RA) | 0.142 | [−4.363; 4.648] | 0.950 |
| Baseline BMI | −0.115 | [−0.499; 0.269] | 0.554 |
| Baseline HbA1c | −0.458 | [−1.878; 0.962] | 0.524 |
| Baseline SBP | −0.737 | [−0.860; −0.614] | <0.0001 |
| SGLT2i (yes vs. no) | −2.192 | [−6.469; 2.085] | 0.313 |
| Predictive Variable | DBP Change | ||
| β-estimate | 95% CI | p-value | |
| Age | −0.070 | [−0.229; 0.089] | 0.384 |
| Sex (Male) | −0.769 | [−3.851; 2.312] | 0.622 |
| scGLP-1RA (vs. oral GLP-1RA) | 3.637 | [0.153; 7.121] | 0.041 |
| Baseline BMI | 0.025 | [−0.269; 0.319] | 0.867 |
| Baseline HbA1c | −0.747 | [−1.844; 0.350] | 0.180 |
| Baseline DBP | −0.798 | [−0.962; −0.633] | <0.0001 |
| SGLT2i (yes vs. no) | 2.249 | [−1.070; 5.567] | 0.182 |
| Predictive Variable | Total Cholesterol Change | ||
| β-estimate | 95% CI | p-value | |
| Age | −0.117 | [−0.628; 0.393] | 0.651 |
| Sex (Male) | −10.244 | [−20.258; −0.230] | 0.045 |
| scGLP-1RA (vs. oral GLP-1RA) | −2.527 | [−13.206; 8.152] | 0.641 |
| Baseline BMI | 0.190 | [−0.705; 1.085] | 0.676 |
| Baseline HbA1c | 4.214 | [1.005; 7.423] | 0.010 |
| Baseline total cholesterol | −0.729 | [−0.835; −0.623] | <0.0001 |
| SGLT2i (yes vs. no) | −15.490 | [−25.955; −5.025] | 0.004 |
| Predictive Variable | Triglyceride Change | ||
| β-estimate | 95% CI | p-value | |
| Age | 0.170 | [−0.719; 1.059] | 0.706 |
| Sex (Male) | 18.279 | [0.702; 35.856] | 0.042 |
| scGLP-1RA (vs. oral GLP-1RA) | 7.052 | [−11.704; 25.807] | 0.459 |
| Baseline BMI | 1.128 | [−0.451; 2.707] | 0.160 |
| Baseline HbA1c | 3.393 | [−2.412; 9.197] | 0.250 |
| Baseline triglycerides | −0.830 | [−0.858; −0.801] | <0.0001 |
| SGLT2i (yes vs. no) | −5.815 | [−24.390; 12.760] | 0.538 |
| Predictive Variable | LDL Cholesterol Change | ||
| β-estimate | 95% CI | p-value | |
| Age | −0.525 | [−0.968; −0.081] | 0.021 |
| Sex (Male) | −1.661 | [−10.596; 7.275] | 0.714 |
| scGLP-1RA (vs. oral GLP-1RA) | 0.946 | [−8.423; 10.315] | 0.842 |
| Baseline BMI | −0.042 | [−0.824; 0.740] | 0.916 |
| Baseline HbA1c | 2.800 | [−0.508; 6.109] | 0.097 |
| Baseline LDL cholesterol | −0.749 | [−0.882; −0.616] | <0.0001 |
| SGLT2i (yes vs. no) | −12.849 | [−22.462; −3.236] | 0.009 |
| Variable | Oral GLP-1RA (n = 55) | scGLP-1RA (n = 55) | p-Value | |
|---|---|---|---|---|
| Age (years) | 69 (64–77) | 71 (67–76) | 0.36 | |
| Sex (n; %) | M | 35/55 (63.6%) | 38/55 (69.1%) | 0.545 |
| F | 20/55 (36.4%) | 17/55 (30.9%) | ||
| Diabetes duration (years) | 14 (8–24) | 15 (9–25) | 0.51 | |
| Baseline HbA1c (%) | 7.1 (6.5–8.4) | 7.6 (6.8–8.1) | 0.272 | |
| Baseline BMI (kg/m2) | 31.4 (28.4–35.3) | 32 (28.8–35.5) | 0.763 | |
| Dose of oral semaglutide (mg) | 3 mg | 3/55 (5.5%) | NA | |
| 7 mg | 12/55 (21.8%) | |||
| 14 mg | 40/55 (72.7%) | |||
| Dose of subcutaneous semaglutide (mg) | 0.5 mg | NA | 13/55 (23.6%) | |
| 1 mg | 42/55 (76.4%) | |||
| Monotherapy (Yes) (n; %) | 5/55 (9.1%) | 4/55 (7.3%) | 0.728 | |
| Semaglutide (n; %) | SWITCH | 40/55 (72.7%) | 40/55 (72.7%) | 1 |
| ADD-ON | 15/55 (23.7%) | 15/55 (27.3%) | ||
| Metformin (Yes) (n; %) | 33/55 (60.0%) | 37/55 (67.3%) | 0.428 | |
| SGLT2i (Yes) (n; %) | 30/55 (54.5%) | 13/55 (23.6%) | 0.001 | |
| Insulin (Yes) (n; %) | 21/55 (38.2%) | 19/55 (34.5%) | 0.692 | |
| SU (Yes) (n; %) | 5/55 (9.1%) | 16/55 (29.1%) | 0.008 | |
| Pioglitazone (Yes) (n; %) | 3/55 (5.5%) | 5/55 (9.1%) | 0.463 | |
| Treatment discontinuation (Yes) (n; %) | 6/55 (10.9%) | 3/55 (5.5%) | 0.297 |
| Predictive Variable | HbA1c Change | ||
|---|---|---|---|
| β-estimate | 95% CI | p-value | |
| Age | 0.006 | [−0.012;0.025] | 0.504 |
| Sex (Male) | −0.261 | [−0.622;0.099] | 0.153 |
| scGLP-1RA (vs. oral GLP-1RA) | 0.284 | [−0.073; 0.641] | 0.118 |
| Baseline HbA1c | −0.714 | [−0.843; −0.585] | <0.0001 |
| SGLT2i (yes) | 0.523 | [0.165; 0.880] | 0.004 |
| Sulphonylureas (yes) | 0.540 | [0.100; 0.980] | 0.016 |
| Predictive Variable | BMI Change | ||
| β-estimate | 95% CI | p-value | |
| Age | 0.001 | [−0.044; 0.048] | 0.943 |
| Sex (Male) | 0.489 | [−0.363; 1.342] | 0.257 |
| scGLP-1RA (vs. oral GLP-1RA) | 0.163 | [−0.690; 1.016] | 0.704 |
| Baseline BMI | −0.062 | [−0.149; −0.025] | 0.160 |
| SGLT2i (yes vs. no) | −0.762 | [−1.621; 0.096] | 0.081 |
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Toffoli, B.; Michieletto, M.; Bernardi, S.; Candido, R. Retrospective Comparative Study of Oral Versus Subcutaneous Semaglutide in Patients with Type 2 Diabetes Mellitus. Int. J. Mol. Sci. 2026, 27, 4694. https://doi.org/10.3390/ijms27114694
Toffoli B, Michieletto M, Bernardi S, Candido R. Retrospective Comparative Study of Oral Versus Subcutaneous Semaglutide in Patients with Type 2 Diabetes Mellitus. International Journal of Molecular Sciences. 2026; 27(11):4694. https://doi.org/10.3390/ijms27114694
Chicago/Turabian StyleToffoli, Barbara, Matteo Michieletto, Stella Bernardi, and Riccardo Candido. 2026. "Retrospective Comparative Study of Oral Versus Subcutaneous Semaglutide in Patients with Type 2 Diabetes Mellitus" International Journal of Molecular Sciences 27, no. 11: 4694. https://doi.org/10.3390/ijms27114694
APA StyleToffoli, B., Michieletto, M., Bernardi, S., & Candido, R. (2026). Retrospective Comparative Study of Oral Versus Subcutaneous Semaglutide in Patients with Type 2 Diabetes Mellitus. International Journal of Molecular Sciences, 27(11), 4694. https://doi.org/10.3390/ijms27114694

