Farxiga Does Not Have Evidence for Treating Pulmonary Hypertension
Farxiga (dapagliflozin) is not indicated for and has not demonstrated benefit in pulmonary arterial hypertension (PAH). The drug's proven benefits are specifically for heart failure (both reduced and preserved ejection fraction) and chronic kidney disease, but these conditions are fundamentally different from primary pulmonary hypertension.
What the Evidence Shows
FDA-Approved Indications
The FDA label for Farxiga 111 makes no mention of pulmonary hypertension as an indication. The approved uses are limited to:
- Heart failure with reduced or preserved ejection fraction
- Type 2 diabetes mellitus
- Chronic kidney disease
Clinical Guidelines Are Silent
Current cardiovascular guidelines 233444 extensively discuss SGLT2 inhibitors for heart failure and cardiorenal protection but do not recommend them for pulmonary arterial hypertension. One guideline 5 explicitly lists "isolated right heart failure or pulmonary hypertension" as an area of uncertainty where benefits remain unproven.
Research Evidence Shows Mixed and Mostly Negative Results
Animal studies demonstrate no benefit or harm:
- A 2021 rat study 6 found dapagliflozin had no protective effect on experimental pulmonary arterial hypertension, showing no improvement in pulmonary vascular remodeling, right ventricular hypertrophy, or survival
- The authors concluded that "human trials with dapagliflozin for PAH or RV failure should be cautious"
Human studies show only indirect effects through left heart disease:
- One small Japanese study 7 (78 patients with type 2 diabetes) showed dapagliflozin reduced exercise-induced pulmonary pressures, but this was secondary to improved left ventricular filling pressures, not a direct effect on pulmonary vasculature
- A 2024 hemodynamic study 8 in HFpEF patients similarly showed improved pulmonary artery compliance during exercise, but again this was correlated with reductions in pulmonary capillary wedge pressure (left heart pressures), not primary pulmonary vascular effects
- A 2025 randomized trial 9 comparing dapagliflozin plus sildenafil versus dapagliflozin alone in heart failure with pulmonary hypertension found no additional benefit from adding sildenafil, suggesting dapagliflozin's effects are limited to the left heart
The Critical Distinction: PH-LHD vs PAH
This is where clinical context matters enormously:
Pulmonary hypertension due to left heart disease (PH-LHD) may improve with dapagliflozin because the drug treats the underlying left heart failure, which secondarily reduces pulmonary pressures. Studies 108 support this mechanism.
Primary pulmonary arterial hypertension (PAH) is a distinct disease of the pulmonary vasculature itself. Current PAH treatment algorithms 11 focus on four pathways: endothelin-1, nitric oxide, prostacyclin, and bone morphogenetic protein signaling. SGLT2 inhibitors do not target any of these pathways and have no established role in PAH management.
Clinical Bottom Line
If your patient has:
- Primary PAH: Do not use Farxiga. Stick to established PAH therapies (endothelin receptor antagonists, phosphodiesterase-5 inhibitors, prostacyclin analogs, soluble guanylate cyclase stimulators)
- Pulmonary hypertension secondary to left heart failure: Farxiga is indicated for the heart failure itself 233, and any improvement in pulmonary pressures is a welcome secondary benefit, not the primary therapeutic target
- Right heart failure without left heart disease: Evidence is insufficient; this remains an area of uncertainty 5
Common Pitfall to Avoid
Do not confuse the proven benefits of SGLT2 inhibitors in heart failure (which may have associated pulmonary hypertension) with efficacy in treating pulmonary hypertension as a primary disease entity. The animal data 6 showing no direct pulmonary vascular benefit should give pause before extrapolating heart failure trial results to PAH populations.