Comparative Pharmacology
Head-to-head clinical analysis: ENTADFI versus REVATIO.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ENTADFI versus REVATIO.
ENTADFI vs REVATIO
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination of a 5α-reductase inhibitor (finasteride) and a phosphodiesterase 5 inhibitor (tadalafil). Finasteride inhibits type II 5α-reductase, preventing conversion of testosterone to dihydrotestosterone, reducing prostate growth. Tadalafil inhibits PDE5, increasing cGMP in smooth muscle, causing relaxation of the prostate and bladder neck.
REVATIO (sildenafil) is a phosphodiesterase type 5 (PDE5) inhibitor. By inhibiting PDE5, it increases cyclic guanosine monophosphate (cGMP) levels in pulmonary vascular smooth muscle, leading to vasodilation and reduced pulmonary vascular resistance.
5 mg orally once daily.
20 mg orally three times daily, administered 4-6 hours apart.
None Documented
None Documented
Finasteride: terminal half-life ~6-8 hours (range 4-12 h) in young adults, 8 hours in elderly. Tadalafil: terminal half-life ~17.5 hours (range 11-28 h), supporting once-daily dosing.
Terminal elimination half-life ~4 hours (range 3-5 hours) in steady state; similar in pulmonary arterial hypertension patients.
ENTADFI (finasteride 5 mg and tadalafil 5 mg) is a fixed-dose combination. Finasteride is excreted 57% in feces (as metabolites) and 39% in urine (<1% as unchanged). Tadalafil is excreted primarily as metabolites, with 61% in feces and 36% in urine; <0.001% of dose is excreted unchanged in urine.
Primarily hepatic metabolism (CYP3A4) to N-desmethyl sildenafil (active). Renal excretion accounts for ~80% as metabolites; ~13% fecal.
Category C
Category C
5-Alpha Reductase Inhibitor and PDE5 Inhibitor
PDE5 Inhibitor