Are there clinical trials comparing VED therapy to medication or penile rehabilitation protocols after prostate cancer surgery?
Executive summary
Clinical studies of penile rehabilitation after radical prostatectomy exist but solid, large randomized trials comparing vacuum erection device (VED) therapy directly against medication-only or standardized rehabilitation protocols are scarce; reviews note some small randomized trials and mixed results for VED plus drugs versus controls [1] [2]. Major systematic reviews conclude that high-quality, long-term randomized evidence comparing VED alone to PDE5 inhibitors, injections, or combined protocols is limited and the optimal program remains unsettled [2] [3].
1. The promise and the evidence: why VED is part of rehab programs
Clinicians include VEDs in penile rehabilitation because the device artificially induces erections that increase penile oxygenation and may reduce cavernous fibrosis after nerve injury from prostate surgery — a physiologic rationale repeated across reviews and specialty summaries [4] [5]. Several clinical reports and smaller trials have shown short-term improvements in erectile function scores and penile length preservation when a VED is used early and frequently after surgery [6] [1].
2. What clinical trials exist — small randomized studies, not definitive head-to-heads
There are randomized trials involving VEDs, and trials testing nightly PDE5 inhibitors, but large, definitive head‑to‑head randomized trials that pit VED therapy alone against medication-only regimens or against a standardized multimodal rehabilitation protocol are lacking in the literature reviewers surveyed [1] [2]. For example, Köhler and colleagues randomized 28 men to early daily VED versus delayed on‑demand use, and other small randomized and nonrandomized series report benefit at 3–6 months, but sample sizes and follow-up vary [1] [6].
3. Reviews: mixed results and the call for better trials
Systematic reviews and narrative syntheses repeatedly conclude that clinical studies show conflicting results regarding long‑term erectile function recovery and that “solid prospective randomized trials” assessing long‑term benefits of PDE5 inhibitors, intracavernosal injections, or VEDs are still lacking [2] [3]. Authors stress that while preclinical data support rehabilitation, clinical outcomes are heterogeneous and methodology (timing, dose, compliance) differs across studies [2].
4. Typical study designs and endpoints you’ll see in the literature
Trials and observational series tend to vary: some test nightly PDE5 inhibitors (e.g., sildenafil nightly for 36 weeks) and others use daily VED sessions (e.g., 10 minutes/day for 5 months); endpoints include International Index of Erectile Function (IIEF) scores, return of spontaneous erections, and stretched penile length [3] [6]. Meta‑level reviewers note dropout and adherence problems that complicate interpretation [1] [7].
5. Clinical practice vs. evidence — why VEDs remain common
Urology clinics and patient resources continue to recommend combined approaches — oral PDE5 inhibitors, intracavernosal injections, and VEDs — because they can be complementary and some nonrandomized series and smaller RCTs report improved early outcomes and penile length preservation with combined use [8] [5]. Professional guidance acknowledges the evidence gap but favors individualized, early rehabilitation strategies while calling for better trials [8] [9].
6. What’s missing from current reporting — the specific gap you asked about
Available sources repeatedly state that few trials directly compare VED therapy alone versus medication-only regimens or versus standardized penile‑rehab protocols in adequately powered, long-term randomized designs; reviewers identify this as an unresolved question and recommend further RCTs [2] [1]. In short: comparative effectiveness trials of VED-alone versus other single or combined modalities are limited or small-scale [2].
7. How to interpret the current evidence if you’re a patient or clinician
Interpret current findings as suggestive rather than conclusive: VEDs have physiologic rationale and some trial-level evidence for short-term benefits and penile length preservation, but long-term superiority over medications or of any single protocol is unproven in large RCTs [4] [2]. Discuss realistic goals, adherence challenges, and the option of combined therapy with your surgeon or sexual-health specialist [8] [7].
Limitations and transparency: this analysis synthesizes the provided literature and systematic reviews; available sources do not mention any large, contemporary randomized trials conclusively comparing VED-alone to medication-only or to a single standardized rehabilitation protocol in adequately powered, long-term studies [2] [1].