Once-daily and on-demand tadalafil have similar efficacy for ED
A once-daily dose of the selective phosphodiesterase 5 (PDE5) inhibitor tadalafil was as effective as an on-demand or as-needed (pro re nata [PRN]) regimen for erectile dysfunction (ED), according to a meta-analysis.
“[O]ur study suggests that tadalafil once a day [OAD] could be used as an alternative to tadalafil [PRN] … In clinical practice … dosing regimen [should be offered] on the basis of individual characteristics and patient preference,” said the researchers.
Researchers evaluated 1,534 participants from six randomized trials using the International Index of Erectile Function (IIEF) scores and Sexual Encounter Profile (SEP), a journal evaluating an individual’s sexual encounters. SEP questions used in particular were SEP-2, which evaluates ability to penetrate, and SEP-3, which pertains to the length of time the erection lasted for a successful intercourse. [Urol Int 2017;doi:10.1159/000477496]
Overall analysis of the IIEF domain scores revealed no significant difference between OAD and PRN regimens (overall pooled estimated weighted mean differences [WMD], 0.97, 95 percent confidence interval [CI], -0.37 to 2.32; p=0.16).
Tadalafil OAD was superior to PRN for SEP-2 (overall pooled WMD, 10.32, 95 percent CI, 3.16–17.48; p=0.005) and SEP-3 (overall pooled WMD, 11.07, 95 percent CI, 2.57–19.56; p=0.01).
Adverse events associated with tadalafil use (ie, headache, dyspepsia, flushing, backache, and myalgia) were relatively rare (2.7 percent [OAD] vs 2.1 percent [PRN]), and were mostly mild and well tolerated.
The lower incidence of headache and flushing in the OAD vs PRN regimen was attributed to a possible association to peak drug plasma concentration, which was much lower in the OAD regimen than the PRN regimen.
The researchers underscored the probable impact of tadalafil dosing on psychological issues which, in turn, may eventually influence sexual performance and quality of life.
“In theory, a much longer effective plasma concentration could be maintained with [OAD] dosing regimen than with [PRN], allowing patients to feel ready for sexual intercourse at any time, and enabling them to separate drug intake from the act of sexual intercourse,” they said.
Although patients favoured OAD over PRN, both regimens were effective and well tolerated. However, selecting the optimal regimen might be complicated due to factors such as ED aetiology, drug efficacy, and adverse events, previous ED medications, and/or economic conditions, said the researchers.