In patients with prior exposure to PDE5 inhibitors, increasing the number of sessions of low-intensity shockwave therapy was associated with improving outcomes.
An additive efficacy benefit was observed with an increase in the number of low-intensity shockwave therapy (LiST) sessions received in patients with low-to-moderate erectile dysfunction (ED) and prior exposure to PDE5 inhibitors (PDE5-Is), according to a pooled analysis presented during the 2020 European Association of Urology (EAU) Virtual Congress.1
The improvement in International Index of Erectile Function-Erectile Function (IIEF-EF) scores between baseline and 6 months’ follow-up was significantly higher (P = .0022) among patients with prior PDEF-I treatment receiving 18 sessions of LiST compared with those receiving fewer sessions (6 or 12).
The 18-session cohort was also the only group in which the patient’s initial IIEF-EF score under PDEF-I therapy was not significantly higher than their IIEF-EF score at 6-months’ post-LiST (23.1 versus 22.4, respectively; P = .43).
“The efficacy of 18 LiST sessions (5000 shockwaves/session; energy flux density [EFD] = .05 mJ/mm2) seems to approach the efficacy offered under the maximum dose of PDE5-Is,” said lead study author Ioannis Mykoniatis, MD, MSc, 1st Department Of Urology, Aristotle University of Thessaloniki School of Medicine, Thessaloniki, Greece. “Nevertheless, randomized head-to-head comparison trials between these 2 ED treatment methods are strongly needed to provide more solid scientific data.”
The researchers had a two-fold purpose for undertaking the study. They wanted to examine whether increasing the number of LiST sessions enhanced the efficacy of the treatment in patients with ED. If this proved to be the case, they wanted to compare this efficacy in a group of PDE5-I–treated patients to the pre-LiST initial efficacy the same patients had under PDE5-Is.
The study was a pooled analysis of data from patients who underwent 3 different numbers of LiST sessions: 6, 12, or 18. The data were obtained from 2 prior studies conducted by the same research group. The first trial included patients with vasculogenic ED who responded to PDE5-Is.2 Patients were randomized to receive LiST once or twice a week for 6 weeks. Patients who completed 6-month follow-up were then eligible to receive at an additional 6 sessions.
In the second trial, the researchers were comparing LiST with an EFD level of 0.05 mJ/mm2 versus an EFD level of 0.10 mJ/mm2 in patients with ED3. Patients on the trial had vasculogenic ED and prior PDE5-I use. All patients received 12 treatment sessions, at 2 or 3 sessions per week.
The pooled analysis presented during the EAU congress included 21 patients who had received 6 LiST sessions, 84 who had received 12 sessions, and 18 who had received 18 sessions. All were previously treated with PDE5-Is and underwent a 4-week washout period prior to starting LiST. All patients received an EFD level of 0.05 ml/mm2.
The 6-month increase in IIEF-EF scores compared with the baseline measurement right before LiST was 3.1, 5.1, and 7.2, among those receiving 6, 12, and 18 sessions, respectively. In the 6-session group, the IIEF-EF score under PDEF-Is was 23.5, compared to the 6-month LiST follow-up score of 19.3. In the 12-session cohort, the scores were 24 versus 21.9 respectively. However, as mentioned, in the 18-session group, the scores were highly similar at 23.1 under PDEF-Is compared with 22.4 at 6 months’ post-LiST.
Mykoniatis explained some of the limitations of his group’s analysis, including that the 2 randomized trials from which the data were pulled were not comparing the efficacy of LiST versus PDE5-Is in ED as their primary end point. Another limitation was that lack of uniformity in the type, frequency, and time period among the patients’ use of PDE5-Is. The third limitation was the relatively small patient population, particularly in the groups receiving either 6 or 18 LiST sessions.
Following his presentation, Mykoniatis was asked by a moderator which patients with ED were ideal for receiving shockwave therapy.
“The latest guidelines say shockwave therapy would be an option for patients with mild-to-moderate ED. For the patients with severe ED who do not respond to PDE5-Is, I do not think these patients are the proper patients to treat with shockwave,” Mykoniatis explained.
1. Mykoniatis I, Kalyvianakis D, Kapoteli P, et al. Can low intensity shockwaves therapy compete the efficacy of PDE5is? A pooled data analysis from 2 randomized clinical trials. 2020 European Association of Urology Virtual Congress. July 17-26, 2020. Abstract 494.
2. Kalyvianakis D, Memmos E, Mykoniatis I, et al. Low-Intensity Shockwave Therapy for Erectile Dysfunction: A Randomized Clinical Trial Comparing 2 Treatment Protocols and the Impact of Repeating Treatment. J Sex Med. 2018;15(3):334-345. doi: 10.1016/j.jsxm.2018.01.003
3. Kalyvianakis D, Mykoniatis I, Memmos E, et al. Low-intensity shockwave therapy (LiST) for erectile dysfunction: a randomized clinical trial assessing the impact of energy flux density (EFD) and frequency of sessions. Int J Impot Res. 2020;32(3):329-337. doi: 10.1038/s41443-019-0185-0