ORLANDO – a post hoc analysis of data from the EXSCEL trial suggested.
Sharon Worcester/MDedge News
Dr. Lindsay Clegg
The findings are consistent with those from published cardiovascular outcomes trials (CVOTs) of sodium-glucose transporter 2 (SGLT2) inhibitors other than dapagliflozin, real-world data, and findings from non-CVOTs of dapagliflozin, Lindsay Clegg, PhD, reported in a late-breaking poster at the annual scientific sessions of the American Diabetes Association.
In EXSCEL – a CVOT of once-weekly treatment with the glucagonlike peptide–1 receptor agonist exenatide added to usual care in patients with type 2 diabetes mellitus – 10% of patients took an SGLT2 inhibitor, and about half of those took dapagliflozin. For the current analysis, the effects of all SGLT2 inhibitors and dapagliflozin alone were evaluated in EXSCEL patients who received placebo.
“Just looking at that placebo data, we wanted to ask what the impact of SGLT2 inhibition was on the adjudicated cardiovascular events, as well as all-cause death and eGFR [estimated glomerular filtration rate] in this population,” Dr. Clegg, a postdoctoral fellow with the AstraZeneca Quantitative Clinical Pharmacology Group in Gaithersburg, Md., said in an interview.
In two propensity-matched cohorts, including a cohort of 709 SGLT2 inhibitor users and a cohort of 709 non-SGLT2 inhibitor users, SGLT2 inhibitors and dapagliflozin alone were found to numerically decrease the major adverse cardiac event (MACE) hazard ratio, and SGLT2 inhibitors significantly reduced all-cause mortality risk, she explained.
MACE events – a composite endpoint of cardiovascular death, nonfatal MI, or nonfatal stroke – occurred in 28 versus 44 patients in the SGLT2 and non-SGLT2 inhibitor groups, respectively (event rate per 100 patient-years, 3.41 vs. 4.45; adjusted HR, 0.79). Dr. Clegg noted that this hazard ratio is “very consistent with what has been seen in the CVOTs for [the SGLT2 inhibitors] empagliflozin and canagliflozin in literature.”
The corresponding figures for dapagliflozin were 11 versus 22 events (event rate per 100 patient-years, 2.69 vs. 4.54; aHR, 0.55).
“So those weren’t statistically significant, but those point estimates were very similar to literature,” she said.
All-cause mortality events occurred in 14 versus 37 patients in the SGLT2 and non-SGLT2 inhibitor groups, respectively (event rate per 100 patient-years, 1.61 vs. 3.34; aHR, 0.50), and in 7 versus 13 dapagliflozin patients within these groups, respectively (event rate per 100 patient-years, 1.62 vs. 2.42; aHR, 0.66).
The overall SGLT2 inhibitor all-cause mortality findings were very similar to what was seen in CVD-REAL, a real-world evidence trial which looked at cardiovascular outcomes in new users of SGLT-2 inhibitors, and the differences were statistically significant for the treatment effect.
“For dapagliflozin, the numbers were pretty similar as well. Not statistically significant, because the number of subjects was smaller, but similar,” Dr. Clegg said.
“On eGFR looking at renal function ... subjects not using an SGLT2 inhibitor had about a 1 mL/min per year decline, which is what we would expect for this population. At baseline the median eGFR was about 80, so it’s a fairly healthy population, because exenatide isn’t used in people with poor renal function,” she explained.
The effects of SGLT2 inhibitors overall, and dapagliflozin alone, were associated with the statistically significant increase in the eGFR slope over time – an outcome that the Food and Drug Administration now recognizes as a surrogate endpoint for renal outcomes, she added. “And again, that’s very consistent with what was seen for [the SGLT2 inhibitor empagliflozin] in the literature.”
Empagliflozin and canagliflozin (another SGLT2 inhibitor) have been shown to reduce MACE, all-cause mortality, and renal events in CVOTs, and real-world evidence suggests a class effect benefit, but dapagliflozin CVOT data have not yet been published.
“Overall this was a nice dataset where we had these adjudicated events to look at outcomes with SGLT2 inhibitors and with [dapagliflozin] specifically, and what we see is very encouraging and suggestive of a class effect,” she concluded, noting that findings from the ongoing phase 3 DECLARE-TIMI58 dapagliflozin CVOT should be released later this year.
Dr. Clegg is employed by AstraZeneca. She reported having no other disclosures.
SOURCE: Clegg L et al. ADA 2018, Abstract 130-LB.