Comparative Pharmacology
Head-to-head clinical analysis: ATMEKSI versus CIALIS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ATMEKSI versus CIALIS.
ATMEKSI vs CIALIS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
ATMEKSI (atazanavir/cobicistat) is a fixed-dose combination of atazanavir, an HIV-1 protease inhibitor that inhibits viral protease, preventing cleavage of viral polyproteins and resulting in immature non-infectious virions, and cobicistat, a pharmacokinetic enhancer that inhibits CYP3A, increasing atazanavir exposure.
Phosphodiesterase-5 (PDE5) inhibitor; increases cGMP levels, causing smooth muscle relaxation and vasodilation in the corpus cavernosum, enhancing erectile function.
1.5 mg/kg IV every 4 weeks
Tadalafil 10 mg or 20 mg orally as needed at least 30 minutes before sexual activity; maximum dosing frequency once daily. Alternative: 2.5 mg or 5 mg once daily for daily use.
None Documented
None Documented
Terminal elimination half-life is 12 hours; renally impaired patients have prolonged half-life up to 24 hours.
The terminal elimination half-life of tadalafil is approximately 17.5 hours in healthy subjects, which supports once-daily dosing for erectile dysfunction and once-daily use for benign prostatic hyperplasia. This long half-life distinguishes it from other PDE5 inhibitors.
Primarily renal (80% unchanged) and biliary/fecal (15% as metabolites).
Following oral administration, tadalafil is predominantly eliminated by hepatic metabolism. The metabolites are excreted mainly in feces (approximately 61% of the dose) and to a lesser extent in urine (approximately 36% of the dose). No unchanged parent drug is detected in urine.
Category C
Category C
PDE5 Inhibitor
PDE5 Inhibitor