From evidence to practice: Insights from the GWTG-HF Registry on the Applicability of FDA Labeling for Dapagliflozin in Heart Failure with Reduced Ejection Fraction

Aaysha Cader, MD, MRCP

Sodium-glucose co-transporter-2 (SGLT-2) inhibitors continue to amaze the world of cardiovascular pharmacotherapeutics. Initially developed as anti-diabetic agents, SGLT-2 inhibitors have demonstrated a wide range of benefits across various patient subsets, most notably those with heart failure.

The landmark Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF) trial, a phase 3, placebo-controlled trial the results of which were published in November 2019, demonstrated that the SGLT-2 inhibitor dapagliflozin reduced mortality and worsening heart failure events, and improved health-related quality of life among patients with heart failure with reduced ejection fraction (HFrEF), regardless of the presence or absence of diabetes.1

Based on these DAPA-HF trial results, in May 2020, dapagliflozin was the first SGLT-2 inhibitor approved by the US Food and Drug Administration (FDA) for HFrEF.2 However, as previous registries have shown, many novel evidence-based therapies are either delayed or not optimally utilized in practice. 3,4 Thus, in order to determine the proportion of eligible candidates for the initiation of dapagliflozin and define potential barriers to therapeutic optimization, an analysis of the American Heart Association (AHA)’s The Get With The Guidelines®–Heart Failure (GWTG-HF) registry was undertaken by Vaduganathan and colleagues. This blog is a summary of the results of this analysis, part of TRANSLATE-HF research platform, the results of which were presented at AHA Scientific Sessions 2020, with simultaneous publication in  JAMA Cardiology.5

The GWTG-HF registry: This a large contemporary hospital-based quality improvement registry including a total of 586,580 patients from 529 sites across the United States.

Population of interest: After exclusion criteria were applied, the primary study cohort for this analysis included 154,714 patients hospitalized with HFrEF at 406 sites between January 2014 – September 2019. As with DAPA-HF, the focus was on chronic HFrEF (≤40%) and treatment eligibility of patients based on discharge parameters during the transition to ambulatory care.

Treatment candidates for Dapagligflozin: The FDA label excluded patients with type 1 diabetes and chronic kidney disease (i.e. estimated glomerular filtration rate [eGFR]<30 mL/min/1.73 m2 and dialysis). When this FDA label was applied to patients in the above cohort, 81.1% would be candidates for dapagliflozin, with similar proportions across all study years (range 80.4-81.7%). When analyzed for 355 sites with ≥10 hospitalizations (enrolling 154,522 patients), the median proportion of FDA label candidates was similar, at 81.1%.

Eligibility according to diabetic status: Notably, the proportion of eligible patients for dapagliflozin was higher among those withOUT a history of or new diagnosis of diabetes, as compared with those with type 2 diabetes (85.5% vs. 75.6%).

Reasons for not meeting FDA label: The predominant reason for ineligibility for dapagliflozin in this cohort was an eGFR<30 mL/min/1.73 m2 at discharge; this was more frequent among diabetics (23.9%) than non-diabetics (14.3%). Other reasons were far less frequent: 3.2% were ineligible due to chronic dialysis and only 0.02% due to type 1 diabetes.

Especially in terms of ineligibility for Dapagliflozin reported in this publication, it is important to note that this data analysis was undertaken between April 1st to June 30th, 2020. More compelling data from two other pivotal SGLT-2 trials reported after DAPA-HF are likely to further extend SGLT-2 inhibitor treatment indications to patients with more severe CKD. DAPA CKD (Dapagliflozin and Prevention of Adverse Outcomes in Chronic Kidney Disease6 evaluated patients with albuminuric chronic kidney disease with eGFR down to as low as 25mL/min/1.73 m2 and EMPEROR-Reduced7 evaluated patients with HFrEF with eGFR as low as 20mL/min/1.73 m2.

Differences between DAPA-HF Trial Participants vs. FDA Label Candidates in GWTG-HF: Participants in DAPA-HF were younger, less often women, and less often Black compared with participants in GWTG-HF, underscoring the need for greater representation of older adults, women, racial/ethnic minority groups, and those with multiple comorbidities in clinical trials relative to reference usual care (i.e. registry) populations. GWTG-HF registry participants had lower left ventricular EF and eGFR; however, a history of myocardial infarction and percutaneous coronary intervention) were more prevalent among DAPA-HF participants.  The overall prevalence of diabetes was similar between both cohorts (44.1%  in GWTG-HF registry vs 45% in DAPA-HF population). There was a lower use of evidence-based HF medical therapies among GWTG-HF participants, but higher use of implantable-cardioverter defibrillators. Most other clinical characteristics were qualitatively similar between the two groups

Conclusions & implications: A lag from clinical trial to clinical practice is not uncommon for most novel pharmacotherapeutics. However, data from this large, contemporary US hospitalized HF registry show that 4 out of 5 patients with HFrEF, irrespective of type 2 diabetes status are candidates for initiation of dapagliflozin at hospital discharge, supporting broad generalizability to practice. This represents a potential opportunity for in-hospital implementation of evidence-based medical therapies and treatment optimization of stable chronic HFrEF, pending data on safety and efficacy of SGLT2 inhibitors in acute HF (NCT04363697, NCT04298229, NCT04157751).

References

  1. McMurray JJV, Solomon SD, Inzucchi SE, et al. Dapagliflozin in patients with heart failure and reduced ejection fraction. N Engl J Med. 2019;381(21):1995-2008.
  2. US Food and Drug Administration. FDA approves new treatment for a type of heart failure. Available at: https://www.fda.gov/news-events/press-announcements/fda-approves-new-treatment-type-heart-failure. Accessed on December 1, 2020.
  3. Greene SJ, Fonarow GC, DeVore AD, et al. Titration of Medical Therapy for Heart Failure With Reduced Ejection Fraction. J Am Coll Cardiol. 2019;73(19):2365-83.
  4. Greene SJ, Butler J, Albert NM, et al. Medical Therapy for Heart Failure With Reduced Ejection Fraction: The CHAMP-HF Registry. J Am Coll Cardiol. 2018;72(4):351-66.
  5. Vaduganathan M, Greene SJ, Zhang S, et al. Applicability of US Food and Drug Administration Labeling for Dapagliflozin to Patients With Heart Failure With Reduced Ejection Fraction in US Clinical Practice: The Get With the Guidelines-Heart Failure (GWTG-HF) Registry. JAMA Cardiol. 2020 Nov 13:e205864. doi: 10.1001/jamacardio.2020.5864
  6. Heerspink HJL, Stefánsson BV, Correa-Rotter R. Dapagliflozin in Patients with Chronic Kidney Disease. N Engl J Med. 2020 Oct 8;383(15):1436-1446. doi: 10.1056/NEJMoa2024816. Epub 2020 Sep 24. PMID: 32970396.
  7. Packer M, Anker SD, Butler J, et al. Cardiovascular and renal outcomes with empagliflozin in heart failure. N Engl J Med. 2020;383:1413-24. 32865377.