Overview of Clinical Trials of Dapagliflozin Tablets in Adults with Type 2 Diabetes Mellitus
Dapagliflozin tablet has been studied in adult patients as monotherapy, in combination with metformin, sulfonylurea (glimepiride), compared to a sulfonylurea (glipizide). Dapagliflozin tablet has also been studied in adult patients with type 2 diabetes mellitus and moderate renal impairment.
Treatment with dapagliflozin tablets as monotherapy and in combination with metformin, glimepiride, produced statistically significant improvements in mean change from baseline at Week 24 in HbA1c compared to control. Reductions in HbA1c were seen across subgroups including gender, age, race, duration of disease, and baseline body mass index (BMI).
Monotherapy
A total of 840 treatment-naive adult patients with inadequately controlled type 2 diabetes mellitus participated in 2 placebo-controlled trials to evaluate the safety and efficacy of monotherapy with dapagliflozin tablets.
In one monotherapy trial, a total of 558 treatment-naive patients with inadequately controlled diabetes participated in a 24-week trial (NCT00528372). Following a 2-week diet and exercise placebo lead-in period, 485 patients with HbA1c ≥7% and ≤10% were randomized to dapagliflozin tablet 5 mg or dapagliflozin tablet 10 mg once daily in either the morning (QAM, main cohort) or evening (QPM), or placebo.
At Week 24, treatment with dapagliflozin tablet 10 mg QAM provided significant improvements in HbA1c and the fasting plasma glucose (FPG) compared with placebo (see Table 7).
Table 7: Results at Week 24 (LOCF*) in a Placebo-Controlled Trial of Dapagliflozin Tablets Monotherapy in Adults with Type 2 Diabetes Mellitus (Main Cohort AM Doses) Efficacy Parameter | Dapagliflozin 10 mg N=70† | Dapagliflozin 5 mg N=64† | Placebo N=75† |
HbA1c (%) |
Baseline (mean) | 8.0 | 7.8 | 7.8 |
Change from baseline (adjusted mean‡) | −0.9 | −0.8 | −0.2 |
Difference from placebo (adjusted mean‡) (95% CI) | −0.7§ (−1.0, −0.4) | −0.5 (−0.8, −0.2) | |
Percent of patients achieving HbA1c <7% adjusted for baseline | 50.8%¶ | 44.2%¶ | 31.6% |
FPG (mg/dL) |
Baseline (mean) | 166.6 | 157.2 | 159.9 |
Change from baseline (adjusted mean‡) | −28.8 | −24.1 | −4.1 |
Difference from placebo (adjusted mean‡) (95% CI) | −24.7§ (−35.7, −13.6) | −19.9 (−31.3, −8.5) | |
* LOCF: last observation (prior to rescue for rescued patients) carried forward. |
† All randomized patients who took at least one dose of double-blind trial medication during the short-term double-blind period. |
‡ Least squares mean adjusted for baseline value. |
§ p-value <0.0001 versus placebo. Sensitivity analyses yielded smaller estimates of treatment difference with placebo. |
¶ Not evaluated for statistical significance as a result of the sequential testing procedure for the secondary endpoints. |
Initial Combination Therapy with Metformin XR
A total of 1236 treatment-naive adult patients with inadequately controlled type 2 diabetes mellitus (HbA1c ≥7.5% and ≤12%) participated in 2 active-controlled trials of 24-week duration to evaluate initial therapy with dapagliflozin tablet 5 mg or 10 mg in combination with metformin extended-release (XR) formulation.
In one trial (NCT00859898), 638 patients randomized to 1 of 3 treatment arms following a 1-week lead-in period received: dapagliflozin tablet 10 mg plus metformin XR (up to 2,000 mg per day), dapagliflozin tablet 10 mg plus placebo, or metformin XR (up to 2,000 mg per day) plus placebo. Metformin XR dose was up-titrated weekly in 500 mg increments, as tolerated, with a median dose achieved of 2,000 mg.
The combination treatment of dapagliflozin tablet 10 mg plus metformin XR provided statistically significant improvements in HbA1c and FPG compared with either of the monotherapy treatments and statistically significant reduction in body weight compared with metformin XR alone (see Table 8 and Figure 2). Dapagliflozin tablet 10 mg as monotherapy also provided statistically significant improvements in FPG and statistically significant reduction in body weight compared with metformin alone and was non-inferior to metformin XR monotherapy in lowering HbA1c.
Table 8: Results at Week 24 (LOCF*) in an Active-Controlled Trial of Dapagliflozin Tablet Initial Combination Therapy with Metformin XR
Efficacy Parameter | Dapagliflozin 10 mg + Metformin XR N=211† | Dapagliflozin 10 mg N=219† | Metformin XR N=208† |
HbA1c (%) |
Baseline (mean) | 9.1 | 9.0 | 9.0 |
Change from baseline (adjusted mean‡) | −2.0 | −1.5 | −1.4 |
Difference from dapagliflozin (adjusted mean‡) (95% CI) | −0.5§ (−0.7, −0.3) | | |
Difference from metformin XR (adjusted mean‡) (95% CI) | −0.5§ (−0.8, −0.3) | 0.0¶ (−0.2, 0.2) | |
Percent of patients achieving HbA1c <7% adjusted for baseline | 46.6%# | 31.7% | 35.2% |
FPG (mg/dL) |
Baseline (mean) | 189.6 | 197.5 | 189.9 |
Change from baseline (adjusted mean‡) | −60.4 | −46.4 | −34.8 |
Difference from dapagliflozin (adjusted mean‡) (95% CI) | −13.9§ (−20.9, −7.0) | | |
Difference from metformin XR (adjusted mean‡) (95% CI) | −25.5§ (−32.6, −18.5) | −11.6# (−18.6, −4.6) | |
Body Weight (kg) |
Baseline (mean) | 88.6 | 88.5 | 87.2 |
Change from baseline (adjusted mean‡) | −3.3 | −2.7 | −1.4 |
Difference from metformin XR (adjusted mean‡) (95% CI) | −2.0§ (−2.6, −1.3) | −1.4§ (−2.0, −0.7) | |
* LOCF: last observation (prior to rescue for rescued patients) carried forward.
† All randomized patients who took at least one dose of double-blind trial medication during the short-term double-blind period.
‡ Least squares mean adjusted for baseline value.
§ p-value <0.0001.
¶ Non-inferior versus metformin XR.
# p-value <0.05.
Figure 2: Adjusted Mean Change from Baseline Over Time in HbA1c (%) in a 24-Week Active-Controlled Trial of Dapagliflozin Tablet Initial Combination Therapy with Metformin XR
In a second trial (NCT00643851), 603 patients were randomized to 1 of 3 treatment arms following a 1-week lead-in period: dapagliflozin tablet 5 mg plus metformin XR (up to 2,000 mg per day), dapagliflozin tablet 5 mg plus placebo, or metformin XR (up to 2,000 mg per day) plus placebo. Metformin XR dose was up-titrated weekly in 500 mg increments, as tolerated, with a median dose achieved of 2,000 mg.
The combination treatment of dapagliflozin tablet 5 mg plus metformin XR provided statistically significant improvements in HbA1c and FPG compared with either of the monotherapy treatments and statistically significant reduction in body weight compared with metformin XR alone (see Table 9).
Table 9: Results at Week 24 (LOCF*) in an Active-Controlled Trial of Dapagliflozin Tablet Initial Combination Therapy with Metformin XR
Efficacy Parameter | Dapagliflozin 5 mg + Metformin XR N=194† | Dapagliflozin 5 mg N=203† | Metformin XR N=201† |
HbA1c (%) |
Baseline (mean) | 9.2 | 9.1 | 9.1 |
Change from baseline (adjusted mean‡) | −2.1 | −1.2 | −1.4 |
Difference from dapagliflozin (adjusted mean‡) (95% CI) | −0.9§ (−1.1, −0.6) | | |
Difference from metformin XR (adjusted mean‡) (95% CI) | −0.7§ (−0.9, −0.5) | | |
Percent of patients achieving HbA1c <7% adjusted for baseline | 52.4%¶ | 22.5% | 34.6% |
FPG (mg/dL) |
Baseline (mean) | 193.4 | 190.8 | 196.7 |
Change from baseline (adjusted mean‡) | −61.0 | −42.0 | −33.6 |
Difference from dapagliflozin (adjusted mean‡) (95% CI) | −19.1§ (−26.7, −11.4) | | |
Difference from metformin XR (adjusted mean‡) (95% CI) | −27.5§ (−35.1, −19.8) | | |
Body Weight (kg) | | | |
Baseline (mean) | 84.2 | 86.2 | 85.8 |
Change from baseline (adjusted mean‡) | −2.7 | −2.6 | −1.3 |
Difference from metformin XR (adjusted mean‡) (95% CI) | −1.4§ (−2.0, −0.7) | | |
* LOCF: last observation (prior to rescue for rescued patients) carried forward.
† All randomized patients who took at least one dose of double-blind trial medication during the short-term double-blind period.
‡ Least squares mean adjusted for baseline value.
§ p-value <0.0001.
¶ p-value <0.05.
Add-On Combination Therapy with Other Antidiabetic Agents
Add-On Combination Therapy with a Sulfonylurea
A total of 597 adult patients with type 2 diabetes mellitus and inadequate glycemic control (HbA1c ≥7% and ≤10%) were randomized in this 24-week, placebo-controlled trial to evaluate dapagliflozin tablets in combination with glimepiride (a sulfonylurea) (NCT00680745).
Patients on at least half the maximum recommended dose of glimepiride as monotherapy (4 mg) for at least 8 weeks lead-in were randomized to dapagliflozin tablet 5 mg, dapagliflozin tablet 10 mg, or placebo in addition to glimepiride 4 mg per day. Down-titration of glimepiride to 2 mg or 0 mg was allowed for hypoglycemia during the treatment period; no up-titration of glimepiride was allowed.
In combination with glimepiride, dapagliflozin tablet 10 mg provided statistically significant improvement in HbA1c, FPG, and 2-hour PPG, and statistically significant reduction in body weight compared with placebo plus glimepiride at Week 24 (see Table 12). Statistically significant (p<0.05 for both doses) mean changes from baseline in systolic blood pressure relative to placebo plus glimepiride were −2.8 mmHg and −3.8 mmHg with dapagliflozin tablets 5 mg and 10 mg plus glimepiride, respectively.
Table 12: Results of 24-Week (LOCF*) Placebo-Controlled Trials of Dapagliflozin Tablets in Combination with Antidiabetic Agent
| Efficacy Parameter | Dapagliflozin 10 mg | Dapagliflozin 5 mg | Placebo |
|---|
In Combination with Sulfonylurea (Glimepiride) |
Intent-to-Treat Population | N=151† | N=142† | N=145† |
HbA1c (%) |
Baseline (mean) | 8.1 | 8.1 | 8.2 |
Change from baseline (adjusted mean‡) | −0.8 | −0.6 | −0.1 |
Difference from placebo (adjusted mean‡) (95% CI) | −0.7§ (−0.9, −0.5) | −0.5§ (−0.7, −0.3) | |
Percent of patients achieving HbA1c <7% adjusted for baseline | 31.7%§ | 30.3%§ | 13.0% |
FPG (mg/dL) |
Baseline (mean) | 172.4 | 174.5 | 172.7 |
Change from baseline (adjusted mean‡) | −28.5 | −21.2 | −2.0 |
Difference from placebo (adjusted mean‡) (95% CI) | −26.5§ (−33.5, −19.5) | −19.3§ (−26.3, −12.2) | |
2-hour PPG¶(mg/dL) |
Baseline (mean) | 329.6 | 322.8 | 324.1 |
Change from baseline (adjusted mean‡) | −60.6 | –54.5 | −11.5 |
Difference from placebo (adjusted mean‡) (95% CI) | −49.1§ (−64.1, −34.1) | −43.0§ (–58.4, −27.5) | |
Body Weight (kg) |
Baseline (mean) | 80.6 | 81.0 | 80.9 |
Change from baseline (adjusted mean‡) | −2.3 | −1.6 | −0.7 |
Difference from placebo (adjusted mean‡) (95% CI) | −1.5§ (−2.2, −0.9) | −0.8§ (−1.5, −0.2) | |
* LOCF: last observation (prior to rescue for rescued patients) carried forward.
† Randomized and treated patients with baseline and at least 1 post-baseline efficacy measurement.
‡ Least squares mean adjusted for baseline value based on an ANCOVA model.
§ p-value <0.0001 versus placebo.
¶ 2-hour PPG level as a response to a 75-gram oral glucose tolerance test (OGTT).
Use in Adults with Type 2 Diabetes Mellitus and Moderate Renal Impairment
Dapagliflozin was assessed in two placebo-controlled trials of adult patients with type 2 diabetes mellitus and moderate renal impairment.
Patients with type 2 diabetes mellitus and an eGFR between 45 to less than 60 mL/min/1.73 m2 inadequately controlled on current diabetes therapy participated in a 24-week, double-blind, placebo-controlled clinical trial (NCT02413398). Patients were randomized to either dapagliflozin tablets 10 mg or placebo, administered orally once daily. At Week 24, dapagliflozin provided statistically significant reductions in HbA1c compared with placebo (Table 13).
Table 13: Results at Week 24 of Placebo-Controlled Trial for Dapagliflozin tablets in Adults with Type 2 Diabetes Mellitus and Renal Impairment (eGFR 45 to less than 60 mL/min/1.73 m2) | | Dapagliflozin 10 mg | Placebo |
|---|
* Least squares mean adjusted for baseline value; at Week 24, HbA1c was missing for 5.6% and 6.8% of individuals treated with dapagliflozin and placebo, respectively. Retrieved dropouts, i.e., observed HbA1c at Week 24 from subjects who discontinued treatment, were used to impute missing values in HbA1c. † p-value =0.008 versus placebo. |
Number of patients: | N=160 | N=161 |
HbA1c (%) |
Baseline (mean) | 8.3 | 8.0 |
Change from baseline (adjusted mean*) | -0.4 | -0.1 |
Difference from placebo (adjusted mean*) (95% CI) | -0.3† (-0.5, -0.1) | |
Pediatric use information is approved for AstraZeneca AB’s Farxiga® (dapagliflozin) Tablets. However, due to AstraZeneca AB’s marketing exclusivity rights, this drug product is not labeled with that information.