International Journal of Drug Delivery Technology
Volume 15, Issue 2

RP-HPLC-Based Stability-Indicating Analytical Method for Concurrent Determination of Finasteride and Tadalafil: Development and ValidationTop of FormBottom of Form

Palanisamy M1*, Dantinapalli V L S2, Elumalai S2, Syed M A3

*1Department of Chemistry, Acharya Nagarjuna University, Namburu, Guntur district, Andhra Pradesh, India

2Department of Chemistry, Raffles University, Neemrana, Alwar, Rajasthan 301705, India

3Senior Scientist, Analytical R&D (AR&D), LRF Pharma Pvt Ltd in Hyderabad, India 

Received: 12th Apr, 2025; Revised: 25th, May, 2025; Accepted: 12th Jun, 2025; Available Online: 25th Jun, 2025 

ABSTRACT

A stability-indicating RP-HPLC method was developed for the simultaneous estimation of Finasteride and Tadalafil using a Symmetry C18 column and an Acetonitrile:0.1% TEA buffer (pH 2.5, 20:80) mobile phase. Detection at 257 nm, flow rate of 1.0 mL/min, and 6-minute runtime ensured effective separation. The method showed linearity from 12.5–75 µg/mL with R² > 0.999, precision with %RSD < 2%, and LOD/LOQ values of 0.60 µg/mL and 2.00 µg/mL. Assay results for the marketed formulation (ENTADFI) showed 100.0% and 100.2% for Finasteride and Tadalafil, respectively. Forced degradation studies confirmed that Finasteride and Tadalafil were susceptible to degradation under acid, alkali, and oxidative conditions, with maximum degradation observed under acidic (14.0%) and oxidative (14.7%) stress for Finasteride, and under alkali (10.8%) and reduction (14.6%) for Tadalafil. Minimal degradation was seen under thermal and hydrolytic conditions

Keywords: Finasteride, Tadalafil, RP-HPLC, Method, Validation, ICH, Forced degradation

How to cite this article: Mylsamy Palanisamy, Venkata Lakshamana Sagar Dantinapalli, Selvaraja Elumalai, Mastan Ali Syed. RP-HPLC-Based Stability-Indicating Analytical Method for Concurrent Determination of Finasteride and Tadalafil: Development and Validation. International Journal of Drug Delivery Technology. 2025;15(2):649-55. doi: 10.25258/ijddt.15.2.35

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