veliparib (ABT-888)

The "immune+/replication+" showed sensitivity to pembrolizumab (OR = 10.192, p < 0.001) and veliparib/carboplatin (OR = 5.184, p = 0.006), while "immune-/replication-" responded poorly to pembrolizumab (OR = 0.086, p < 0.001). Additionally, "immune+/replication-" had the best distant recurrence-free survival (DRFS), whereas "immune-/replication+" had the worst (log-rank p = 6 × 10-4, HR = 5.45). By linking imaging heterogeneity directly to molecular subtypes and therapeutic response, this framework provides a robust, non-invasive surrogate for genomic profiling and a strategic tool for personalized neoadjuvant therapy selection.

Interestingly, HCT116RPDD cells exhibited greater sensitivity to γ-ray irradiation and the nicotinamide phosphoribosyltransferase (NAMPT) inhibitor FK866 than the parental HCT116 cells, yet showed comparable sensitivity to 5-FU, cisplatin, and PARP inhibitors olaparib, talazoparib, and veliparib. Furthermore, we observed that HCT116RPDD cells tended to maintain slightly higher levels of intracellular NAD+/NADH and ATP compared to parental HCT116 cells. These findings suggest that cancer cells employ a mechanism to regulate NAD+ and ATP levels, thereby avoiding cell death from intracellular PAR accumulation through coordinated PARP-PARG regulation.

Notably, senaparib showed superior PFS efficacy compared to veliparib and niraparib. PARPi showed efficacy in improving PFS as maintenance therapy for newly diagnosed advanced OC, although no OS advantage was observed. PROSPERO (CRD420251020275).

ER10 values for talazoparib, olaparib rucaparib, ABT888 and niraparib were 1.5, 1.8, 2.8, 1.4, and 1.4, respectively. When the p21 gene was knocked down, both the decrease in mitochondrial membrane potential and senescence level were attenuated, suggesting that p21 is involved in senescence induction after γ-irradiation combined with talazoparib treatment. Taken together, we showed that PARP inhibitor talazoparib treatment in combination with γ-irradiation causes cellular senescence in lung cancer cells, involving p21 function.

P1, N=44, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Nov 2025 --> Nov 2026

P1, N=66, Completed, National Cancer Institute (NCI) | Active, not recruiting --> Completed

P2, N=38, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Oct 2025 --> Oct 2026

P1, N=81, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Oct 2025 --> Oct 2026

P1/2, N=64, Completed, Georgetown University | Unknown status --> Completed

Observed treatment efficacy and toxic effects varied across PARP inhibitor regimens; for example, the risk ratio for any recurrence or death in the overall study group ranged from 0.53 (95% CI, 0.40-0.70) for senaparib to 0.83 (95% CI, 0.68-1.00) for olaparib, while the risk ratio for high-grade adverse events ranged from 1.15 (95% CI, 0.64-2.06) for veliparib to 4.73 (95% CI, 2.77-8.07) for niraparib. In this study, no subgroup showed an association between first-line PARP inhibitor maintenance therapy in advanced-stage EOC and improved OS, and findings suggest that the consistency of associated PFS benefits may vary, particularly in homologous recombination proficient and BRCA wild type tumors. Variability in efficacy and toxic effects across subgroups and PARP inhibitor regimens underscores the importance of individualized treatment decisions.

P1/2, N=88, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Aug 2025 --> Aug 2026

PARPi renders cells hypersensitive to end of range high LET proton irradiation. The potential enhanced proton radiosensitization should be considered during clinical trial design with efforts to limit high physical dose and high LET overlap within normal tissues. Planning techniques that increase the LET within tumors warrants further investigation in combination with PARPi as a novel strategy to overcome therapeutic resistance.