AZD-5305 is a highly selective PARP1 inhibitor developed for the treatment of cancers, particularly those with homologous recombination deficiencies such as BRCA mutations. It is designed to maximize tumor cell killing through synthetic lethality while minimizing toxicity to healthy cells by sparing PARP2 inhibition. This selectivity may reduce side effects commonly seen with broader PARP inhibitors, such as hematological toxicity and gastrointestinal issues.

It is being investigated in clinical trials for solid tumors, including breast, ovarian, prostate, and pancreatic cancers. Its potential use in combination with other agents like DNA-damaging chemotherapy or immune checkpoint inhibitors is also under exploration to enhance anti-tumor efficacy. Additionally, AZD-5305 demonstrates good blood-brain barrier penetration, offering potential for treating central nervous system tumors. Due to its targeted mechanism, AZD-5305 holds promise for improving therapeutic outcomes in patients with PARP-sensitive tumors.