Repurposing FDA approved drugs as radiosensitizers for treating hypoxic prostate cancer

Abstract Background The presence of hypoxia is a poor prognostic factor in prostate cancer and the hypoxic tumor microenvironment promotes radioresistance. There is potential for drug radiotherapy combinations to improve the therapeutic ratio. We aimed to investigate whether hypoxia-associated genes could be used to identify FDA approved drugs for repurposing for the treatment of hypoxic prostate cancer. Methods Hypoxia associated genes were identified and used in the connectivity mapping software QUADrATIC to identify FDA approved drugs as candidates for repurposing. Drugs identified were tested in vitro in prostate cancer cell lines (DU145, PC3, LNCAP). Cytotoxicity was investigated using the sulforhodamine B assay and radiosensitization using a clonogenic assay in normoxia and hypoxia. Results Menadione and gemcitabine had similar cytotoxicity in normoxia and hypoxia in all three cell lines. In DU145 cells, the radiation sensitizer enhancement ratio (SER) of menadione was 1.02 in normoxia and 1.15 in hypoxia. The SER of gemcitabine was 1.27 in normoxia and 1.09 in hypoxia. No radiosensitization was seen in PC3 cells. Conclusion Connectivity mapping can identify FDA approved drugs for potential repurposing that are linked to a radiobiologically relevant phenotype. Gemcitabine and menadione could be further investigated as potential radiosensitizers in prostate cancer

Randomised phase III trial of the hypoxia modifier nimorazole added to radiotherapy with benefit assessed in hypoxic head and neck cancers determined using a gene signature (NIMRAD)

Background Tumour hypoxia is an adverse prognostic factor in head and neck squamous cell carcinoma (HNSCC). We assessed whether patients with hypoxic HNSCC benefited from the addition of nimorazole to definitive intensity-modulated radiotherapy (IMRT). Methods NIMRAD was a phase III, multi-centre, placebo controlled, double-anonymized trial in patients with HNSCC unsuitable for concurrent platinum chemotherapy or cetuximab with definitive IMRT (NCT01950689). Patients were randomized 1:1 to receive IMRT (65 Gy in 30 fractions over 6 weeks) plus nimorazole (1.2 g/m2 daily, prior to IMRT) or placebo. The primary endpoint was freedom from loco-regional progression (FFLRP) in patients with hypoxic tumours, defined as greater than or equal to the median tumour hypoxia score of the first 50 patients analysed (≥0.079), using a validated 26-gene signature. The planned sample size was 340 patients allowing for signature generation in 85%, assumed HR 0.50 for nimorazole effectiveness in the hypoxic group, and requiring 66 loco-regional failures to have 80% power in a two-tail log-rank test at the 5% significance level. Results 338 patients were randomised by 19 UK centres from May 2014 to May 2019, with a median follow-up of 3.1 years (95%CI 2.9-3.4). Hypoxia scores were available for 286 (85%). The median patient age was 73 years (range: 44-88, IQR: 70-76). There were 36 (25.9%) loco-regional failures in the hypoxic group, where nimorazole + IMRT did not improve FFLRP (adjusted HR 0.72; 95% CI 0.36-1.44; p=0.35), or overall survival (adjusted HR 0.96; 0.53-1.72; p=0.88) compared with placebo + IMRT. Similarly, nimorazole + IMRT did not improve FFLRP or OS in the whole population. In total (n=338), 73% of patients allocated nimorazole adhered to the drug for ≥50% of IMRT fractions. Nimorazole + IMRT caused more acute nausea compared with placebo + IMRT (CTCAE v4.0 G1+2: 56.6% vs 42.4%, G3: 10.1% vs 5.3%, respectively; p<0.05). Conclusions Addition of the hypoxia modifier nimorazole to IMRT for locally advanced HNSCC in older and less fit patients did not improve loco-regional control or survival

Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry

IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes