The new analysis of dapagliflozin, a diabetes drug, suggests it may cut heart failure risk dramatically for people who carry rare genetic variants tied to cardiomyopathy, based on data from a large randomized trial. Researchers examined over 12,000 adults with type 2 diabetes and elevated cardiovascular risk, focusing on roughly 121 carriers of potentially harmful inherited variants. Results showed a much bigger reduction in heart failure hospitalization among variant carriers compared with noncarriers, though experts advise caution because of sample size and the secondary nature of the analysis.
Researchers mined the DECLARE-TIMI 58 trial to see whether the SGLT2 inhibitor dapagliflozin could do more than control glucose. The trial dataset included more than 12,000 adults with type 2 diabetes and higher cardiovascular risk, giving investigators the chance to study outcomes across genetic subgroups. About 121 participants carried inherited gene variants that have been linked to cardiomyopathy.
When researchers compared outcomes, dapagliflozin reduced hospitalizations for heart failure in both carriers and noncarriers, but the magnitude differed markedly. The reduction was roughly eight times stronger in people carrying the genetic variants compared with those without them. That striking difference is what has clinicians intrigued and cautious at the same time.
Among carriers who had no prior history of heart failure, the contrast was particularly sharp: 12.8% developed heart failure on placebo, while none of the carriers given dapagliflozin experienced heart-failure events during follow-up. The median follow-up was 4.2 years, long enough to pick up meaningful differences in clinical events. Those numbers hint that early treatment in genetically at-risk people could prevent progression to symptomatic disease.
Shinwan Kany’s comments capture the shift this could represent for preventive cardiology. “Historically, identifying a genetic variant for cardiomyopathy mostly meant telling a patient they were at high risk and not having a specific preventive therapy to offer,” he said in a press release. “These data show we do have tools to lower risk in these individuals.”
Outside experts praised the finding as provocative and worthy of follow-up, while warning it is not yet practice-changing. “These findings are very encouraging because they suggest we may be entering an era where heart failure prevention becomes more precise and more genetically informed,” Andrew Freeman, MD, a cardiologist at National Jewish Health, told Fox News Digital. He emphasized that the result generates hypotheses that need confirmation in dedicated studies.
Freeman also urged restraint about immediate clinical rollouts. “This should be viewed as an exciting hypothesis-generating finding, not yet a practice-changing mandate for all patients with these genetic variants,” Freeman cautioned. The trial-based analysis is helpful for spotting signals, but it cannot replace a randomized trial designed specifically to test prevention in genetically defined groups.
Clinicians will note that SGLT2 inhibitors already have a proven track record for cardiovascular and kidney protection across broad patient groups. The class of drugs has repeatedly reduced heart failure hospitalizations in people with diabetes, chronic kidney disease, and established heart failure. What this analysis adds is the possibility of an even larger benefit in a genetically selected subgroup.
The study has limitations that matter for interpretation and for patients weighing treatment options. The number of variant carriers was small, which raises the risk that random variation inflated the observed effect size. Because the genetic subgroup analysis was conducted within a larger trial, the findings are best seen as a signal that needs targeted confirmation.
That confirmation would ideally come from trials or registries designed to recruit people identified by genetic screening, so researchers can test whether early SGLT2 inhibitor therapy prevents the onset of heart failure. Meanwhile, decisions about starting medications should be individualized and discussed with a clinician, especially for people with personal or family histories of cardiovascular disease. Preventive cardiology is evolving, and genetics may soon play a larger role in shaping who gets early therapy and why.
