Sildenafil,
does it really help with Improved six-minute walk capacity and reduced clinical worsening in pulmonary arterial hypertension?
research showsSildenafil improves six-minute walk capacity in pulmonary arterial hypertension but is rated C with 55 points. SUPER-1 randomized 278 participants, treated 277, and included 266 in the primary efficacy analysis. The 20-mg placebo-corrected estimate of +45 m (99% CI 21 to 70) exceeds the approximately 33-m meaningful difference from Mathai 2012, but the lower limit of 21 m does not. PACES found +28.8 m (95% CI 13.9 to 43.8), and both pivotal trials belonged to the Pfizer program.
ads claimPromotion can expand improved walking distance into cure or guaranteed survival. The best-established scope is short-term exercise capacity in symptomatic pulmonary arterial hypertension, not pulmonary hypertension of every cause.
Useful facts when choosing a product
- SUPER-1 tested sildenafil 20, 40, and 80 mg three times daily; approved dosing and prescribing vary by country and clinical context.
- Mathai et al. 2012 estimated the six-minute walk minimal important difference in pulmonary arterial hypertension at approximately 33 m.
- Verdict 629, which is B with 79 points, concerns erectile dysfunction; verdict 1017, which is D with 30 points, concerns exercise performance in healthy people.
What the research actually shows
Galiè 2005 SUPER-1 randomized 278 participants, 277 received at least one dose, and 266 entered the actual primary walking analysis. The primary 12-week six-minute walk endpoint succeeded at every sildenafil dose. Simonneau 2008 PACES randomized 267 participants, 265 received treatment, and 256 contributed postbaseline walking data after nine without such data were excluded. The placebo-adjusted walk effect was +28.8 m, and clinical worsening was 6.2% versus 19.5% (P=0.002). Wang 2014 synthesized four trials and 545 participants, finding +31.3 m and RR 0.39 for clinical worsening. Verdict 629, which is B with 79 points, concerns erectile dysfunction, while verdict 1017, which is D with 30 points, concerns exercise in healthy people.
Why this is classified as C (55)
Six-minute walk distance is itself a patient-important treatment goal, and the SUPER-1 point estimate exceeded the approximately 33-m threshold. The lower confidence limit did not, however, and both SUPER-1 and PACES were Pfizer-program trials, so manufacturer-only confirmation and magnitude uncertainty give C with 55 points.
Counterpoint. Effect varies by cause, functional class, and background therapy; PACES specifically tested add-on treatment to epoprostenol.
Rejudgment record. Cross-check applied — Improvement in the patient-important six-minute walk outcome, tempered because SUPER-1 and PACES were both Pfizer development-program trials and the confidence interval crosses the meaningful-change estimate
| Endpoint | P | Patient-reported treatment goal - the symptom is the goal |
| Replication | R1 | Single confirmatory trial |
| Independence | I0 | Evidence comes only from manufacturer studies |
| Effect size | E+ | Meets the clinically important threshold |
The scoring table and the verdict agree (C).
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Improved six-minute walk distance | C | The +45-m estimate exceeded about 33 m, but the 99% confidence lower limit of 21 m did not. |
| Improved WHO functional class | C | Every dose improved functional class versus placebo in SUPER-1, within the manufacturer program. |
| Reduced clinical worsening | C | PACES found 6.2% versus 19.5% in a Pfizer-sponsored add-on trial to epoprostenol. |
Cross-check — Codex and Claude
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Galiè N et al. 2005 (SUPER-1) | Multicenter randomized double-blind placebo-controlled trial | 266 | Pfizer Global Research and Development | Change in six-minute walk distance at 12 weeks | Placebo-corrected effect was +45 m with 20 mg (99% CI 21 to 70); all doses achieved P<0.001 and the primary endpoint succeeded. | Pivotal confirmatory trial |
| Simonneau G et al. 2008 (PACES) | Randomized double-blind placebo-controlled add-on trial to epoprostenol | 256 | Pfizer | Change in six-minute walk distance at 16 weeks | Placebo-adjusted effect +28.8 m (95% CI 13.9 to 43.8); clinical worsening 6.2% versus 19.5%, P=0.002. | Replication in a separate clinical setting |
Receipt — 3 References
All 3 cited sources were verified for existence at the original page (as of 2026-07-24).
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-24 · Corrections: none
Cite this verdict
[Chamgap] Sildenafil x walking capacity and clinical worsening in pulmonary arterial hypertension — Evidence Grade C·55. 3 cited sources checked. Source: https://chamgap.com/en/verdicts/heart/sildenafil-pulmonary-arterial-hypertension-walking-clinical-worsening/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.