Recent Considerations in the Application of RAPTA-C for Cancer Treatment and Perspectives for Its Combination with Immunotherapies

The organometallic ruthenium(II) [Ru(arene)Cl2PTA] PTA - 1,3,5-triaza-7-phosphaadamantane compound, RAPTA-C, represents an innovative anti-cancer therapeutic and a better-tolerated alternative to platinum (Pt)-based chemotherapeutic drugs in the treatment of cancer. RAPTA-C exhibits anti-metastatic, anti-angiogenic, and anti-tumoral activities through protein and histone-deoxyribonucleic acid alterations. In comparison to other ruthenium-based drugs, which have been recently evaluated in clinical trials, RAPTA-C is strikingly competitive, especially when administered in combination with other targeted drugs. In this review, the uniqueness of RAPTA-C as an anti-cancer chemotherapeutic compared to metal-based drugs under clinical evaluation and those approved by the Food and Drug Administration is emphasized; specifically, comparing the application of RAPTA-C to platinum-based drugs, for example, cisplatin and oxaliplatin, as well as to prominent ruthenium-based compounds, such as NAMI-A imidazolium-trans-tetrachloro(dimethylsulfoxide) imidazoleruthenium(III) and trans-[tetrachlorobis (1Hindazole) ruthenate(III)] (KP1019)/(N)KP1339 (N)KP1339 - sodium. Additionally, the possible correlation between RAPTA-C and immune response modulation, as well as potential applications of RAPTA-C in combination with immune therapeutic regimens, is highlighted.