The study aimed at developing a liquisolid tablet (LST) containing tadalafil (TDL) and dapoxetine(DPX) with improved bioavailability as a potential therapy for male sexual dysfunction. A mixtureof nonvolatile solvents, namely PEG 200 and Labrasol®, was utilized to prepare LSTs that wereassessed for their quality characteristics. The BoxBehnken design (BBD) was employed tostatistically explore the effect of the formulation factors on the quality attributes of LSTs.Furthermore, an in vivo pharmacokinetic study was carried out for the optimized LST incomparison with the marketed tablets on healthy human volunteers. The optimized LST revealedacceptable quality limits with enhanced dissolution for both APIs. The pharmacokineticparameters after oral administration of the optimized LST indicated that the Cmax of TDL in LSTswas 122.61 ng/mL within 2h compared to the marketed tablets, which reached 91.72 ng/mL after3 h, indicating the faster onset of action. The AUC was improved for TDL in LST (4484 vs. 2994ng/mL∙h in the marketed tablet) and DPX in LST (919.633 vs. 794.699 ng/mL∙h in the marketedtablet). This enhancement in bioavailability potentially minimizes the associated side effects andimproves the treatment of male sexual dysfunction, particularly for diabetic patients.

Dr. Fayez Alotaibi has completed his MSc at the age of 40 years from King Abdul Aziz University at

Jeddah, Saudi Arabia and He completed his Mpharm at age of 35 years from Bradford University,

United Kingdom. He is the director for pharmaceutical Services at King Fahd Jeddah General, Saudi

Arabia. He has published more than 3 papers in reputed journals. He is a member of pharmacy

and therapeutic committee. He is a member of morbidity and mortality committee. He is a

member of Quality and Patient Safety Council.