Cancer treatment faces significant challenges, necessitating innovative approaches to predict and enhance drug efficacy. Computational models, particularly advanced machine learning methods, have shown promise in customizing drug response predictions and improving patient outcomes. However, predicting synergistic drug combinations remains complex due to the vast number of potential interactions and the limitations of both data availability and traditional research methodologies. In response, our study introduces SynSimPred, a computational approach that leverages cell line similarities, gene expression, mutations, dependencies, and copy number variations to predict drug synergy scores. SynSimPred employs a suite of sophisticated regression methodologies to navigate the complex interplay between these biological characteristics and their impact on drug efficacy. A key component of our research involved a detailed case study where SynSimPred predicted the synergistic and antagonistic interactions of drug pairs such as Vinblastine and Veliparib, and Deforolimus and Dactolisib, demonstrating its practical utility and accuracy in real-world scenarios. We rigorously evaluated SynSimPred against leading methods including DeepSynergy, HypergraphSynergy, and SynPred, across two comprehensive datasets, O'NEIL and ALMANAC. Our evaluations, using metrics such as MSE, Precision, F-Measure, and Accuracy, demonstrate that SynSimPred consistently outperforms existing models, establishing it as a frontrunner in the field of predictive methodologies for cancer treatment.