RESUMO
The ATR kinase plays a key role in the DNA damage response by activating essential signaling pathways of DNA damage repair, especially in response to replication stress. Because DNA damage and replication stress are major sources of genomic instability, selective ATR inhibition has been recognized as a promising new approach in cancer therapy. We now report the identification and preclinical evaluation of the novel, clinical ATR inhibitor BAY 1895344. Starting from quinoline 2 with weak ATR inhibitory activity, lead optimization efforts focusing on potency, selectivity, and oral bioavailability led to the discovery of the potent, highly selective, orally available ATR inhibitor BAY 1895344, which exhibited strong monotherapy efficacy in cancer xenograft models that carry certain DNA damage repair deficiencies. Moreover, combination treatment of BAY 1895344 with certain DNA damage inducing chemotherapy resulted in synergistic antitumor activity. BAY 1895344 is currently under clinical investigation in patients with advanced solid tumors and lymphomas (NCT03188965).
Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Morfolinas/administração & dosagem , Morfolinas/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/farmacocinética , Administração Oral , Animais , Antineoplásicos/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/química , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Disponibilidade Biológica , Carboplatina/administração & dosagem , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Inibidores do Citocromo P-450 CYP2C8/química , Inibidores do Citocromo P-450 CYP2C8/farmacologia , Reparo do DNA/efeitos dos fármacos , Cães , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Feminino , Humanos , Camundongos SCID , Microssomos Hepáticos/efeitos dos fármacos , Morfolinas/química , Pirazóis/química , Ratos Wistar , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
AIMS: This programme investigated topical regorafenib, a multikinase inhibitor, in patients with neovascular age-related macular degeneration (nAMD). METHODS: Topical regorafenib was investigated in an open-label, phase IIa/b study in which patients with choroidal neovascularization (CNV) secondary to nAMD received regorafenib (25 µl, 30 mg ml-1 ) three times a day for 12 weeks. The primary endpoint of the phase II/a/b study was mean change in best-corrected visual acuity (BCVA) from baseline to weeks 4 and 12. RESULTS: In nAMD patients (N = 51), mean changes in BCVA were +1.2 [90% confidence interval (CI) -0.61, 2.97] and -2.4 (90% CI -4.18, -0.54) letters at weeks 4 and 12, respectively. Ocular treatment-emergent adverse events (TEAEs) (study eye) were reported in 21 patients by week 12. There was one serious ocular TEAE (visual acuity reduced) that was not drug related. Twenty patients required rescue (intravitreal ranibizumab). CONCLUSIONS: The programme was terminated after phase IIa ended because efficacy was lower than with current nAMD treatments. According to elaborate post hoc analyses, the most likely reason was insufficient exposure in the target compartment (back of the eye).
