Further analyses from the cardiovascular outcome trial of the sodium-glucose transporter 2 inhibitor ertugliflozin in patients with type 2 diabetes helped better define positive effects the drug had on preserving renal function, and also gave a tantalizing hint that this drug, and hence possibly the entire SGLT2 inhibitor drug class, may benefit patients with heart failure with reduced ejection fraction.
Dr. Melanie Davies
But the underlying problem for ertugliflozin (Steglatro) – first seen when results from the VERTIS CV trial initially came out in June 2020 at the annual meeting of the American Diabetes Association – was that, while the trial met its primary endpoint of proving noninferiority to placebo for the combined endpoint of cardiovascular death, nonfatal MI, or nonfatal stroke, treatment with ertugliflozin showed no suggestion of benefit, compared with placebo for reducing this endpoint, producing a nonsignificant 3% relative cut in the combined rate of these adverse events, compared with placebo treatment.
‘Somewhat disappointing’ trial performance
Overall, results from VERTIS CV with ertugliflozin were “somewhat disappointing,” commented Melanie J. Davies, MD, who was not involved with the study and chaired a session at the virtual annual meeting of the European Association for the Study of Diabetes that reviewed the main results, put them into perspective, and added a few new exploratory analyses.
Although the results from 8,246-patient VERTIS CV (Evaluation of Ertugliflozin Efficacy and Safety Cardiovascular Outcomes Trial) put ertugliflozin in the same league as other drugs from its class for safety, “we do not see the significant benefits observed in many of the previous cardiovascular outcomes trials” for other drugs in the SGLT2 inhibitor class, specifically canagliflozin (Invokana), dapagliflozin (Farxiga), and empagliflozin (Jardiance), Dr. Davies said in an interview. The upshot, for at least the time being, is that ertugliflozin “is unlikely to receive a label for any new indications,” she predicted. In contrast, the other drugs in the class have, for example, received a U.S. labeled indication to reduce cardiovascular death (empagliflozin) or major cardiovascular disease events (canagliflozin) in adults with type 2 diabetes (T2D) and cardiovascular disease, or to reduce heart failure hospitalizations (dapagliflozin).
The main results from VERTIS CV, posted online in the New England Journal of Medicine after the EASD session, showed a single significant outcome difference between treatment with ertugliflozin and placebo over a median of 3.0 years of follow-up from among 10 reported secondary outcomes: a 30% relative reduction (a 1.1% absolute reduction) in the rate of hospitalization for heart failure, the sole criterion in the report by which ertugliflozin matched the benefits of the other SGLT2 inhibitors.
But the prespecified design of VERTIS CV called for a hierarchical sequence of secondary analyses. The statistically significant noninferiority of the primary endpoint allowed calculation of the initial secondary endpoint, a reduction in the combined rate of cardiovascular death or hospitalization for heart failure. Ertugliflozin treatment cut this outcome by a relative 12%, compared with placebo, a difference that was not significant.
This neutral finding brought to a stop further statistical testing of any of the other secondary endpoints, including impact on hospitalization for heart failure by itself. It also guaranteed that no beneficial effect inferred from the trial’s data would qualify for statistical validity, making it unlikely that ertugliflozin would gain any new label indications from these results. The drug carries a U.S. label that is limited to providing glycemic control.