The present invention is directed to novel substituted 2,4,8-trisubstituted 8H-pyrido[2,3-d]pyrimidin-7-one containing compounds, compositions, and use in therapy as CSBP/RK/p38 kinase inhibitors of Formulas (V) and (Va) wherein inter alia, G5 and G6 are nitrogen and CH, provided that only one of G5 or G6 is nitrogen and the other is CH; R1 is C(Z)N(R10′)(CR10R20)vRb, C(Z)O(CR10R20)vRb, N(R10′)C(Z)(CR10R20)vRb, N(R10′)C(Z)N(R10′)(CR10R20)vRb, or N(R10′)OC(Z)(CR10R20)vRb; R1′ is independently selected at each occurrence from halogen, C1-4 alkyl, halo-substituted-C1-4 alkyl, cyano, nitro, (CR10R20)v′NRdRd′, (CR10R20)v′C(O)R12, SR5, S(O)R5, S(O)2R5, or (CR10R20)v′OR13; Rb is hydrogen, C1-10 alkyl, C3-7 cycloalkyl, C3-7 cycloalkyl C1-10 alkyl, aryl, arylC1-10alkyl, heteroaryl, heteroarylC1-10 alkyl, heterocyclic, or heterocyclylC1-10 alkyl moiety, which moieties, excluding hydrogen, may all be optionally substituted; X is R2, OR2′, S(O)mR2′, (CH2)n′N(R10′)S(O)mR2′, (CH2)n′N(R10′)C(O)R2′, (CH2)n′NR4R14, (CH2)n′N(R2′)(R2″), or N(R10′)RhNH—C(═N—CN)NRqRq′; and R3 is a C1-10 alkyl, C3-7 cycloalkyl, C3-7 cycloalkyl C1-10 alkyl, aryl, arylC1-10 alkyl, heteroaryl, heteroarylC1-10 alkyl, heterocyclic or a heterocyclylC1-10 alkyl moiety, and wherein each of these moieties may be optionally substituted.