¹Department of Pharmaceutical Technology, Faculty of Pharmacy, Erzincan Binali Yıldırım University, 24002, Erzincan, Turkey DOI : 10.29228/jrp.215 Corneal neovascularization (CNV) is a serious ocular surface disease that causes the cornea to lose its transparent structure. It is a difficult disease to treat, so different drugs and different carrier systems are tried in the treatment of the disease. One of these methods is the combined application of metformin HCl (MHL) with a fluoroquinolone group antibiotic. The aim of this study is to load MHL with low permeability into a drug delivery system that can prolong the residence time on the ocular surface. In this context, different in situ gel formulations were produced by using poloxamer, a thermosensitive polymer, together with hydroxypropylmethylcellulose, a natural viscosity increaser. In situ gels were evaluated for clarity, pH, gelation temperature, and rheological behaviors and selected two formulation. After loading MHL and moxifloxacin HCl (MOX) into these two formulations, it was determined that they were clear, had a pH of around 7, a gelling temperature of 34-35 °C, and showed pseudoplastic flow. However, drug loading capacities were found to be over 97%.When in vitro release studies were examined, it was determined that both MHL and MOX released for at least six hours. The results showed that the combination of PF127 and HPMC has potential as an in situ gelling systems for ocular delivery of MHL and MOX. Keywords : Metformin HCl; in situ gel; ocular drug delivery; moxifloxacin HCl; hydroxypropylmethylcellulose