Evofosfamide for the treatment of human papillomavirus-negative head and neck squamous cell carcinoma

Evofosfamide (TH-302) is a clinical-stage hypoxia-activated prodrug of a DNA-crosslinking nitrogen mustard that has potential utility for human papillomavirus (HPV) negative head and neck squamous cell carcinoma (HNSCC), in which tumor hypoxia limits treatment outcome. We report the preclinical efficacy, target engagement, preliminary predictive biomarkers and initial clinical activity of evofosfamide for HPV-negative HNSCC. Evofosfamide was assessed in 22 genomically characterized cell lines and 7 cell line-derived xenograft (CDX), patient-derived xenograft (PDX), orthotopic, and syngeneic tumor models. Biomarker analysis used RNA sequencing, whole-exome sequencing, and whole-genome CRISPR knockout screens. Five advanced/metastatic HNSCC patients received evofosfamide monotherapy (480 mg/m2 qw × 3 each month) in a phase 2 study. Evofosfamide was potent and highly selective for hypoxic HNSCC cells. Proliferative rate was a predominant evofosfamide sensitivity determinant and a proliferation metagene correlated with activity in CDX models. Evofosfamide showed efficacy as monotherapy and with radiotherapy in PDX models, augmented CTLA-4 blockade in syngeneic tumors, and reduced hypoxia in nodes disseminated from an orthotopic model. Of 5 advanced HNSCC patients treated with evofosfamide, 2 showed partial responses while 3 had stable disease. In conclusion, evofosfamide shows promising efficacy in aggressive HPV-negative HNSCC, with predictive biomarkers in development to support further clinical evaluation in this indication.

Effect of acid-suppressive therapy on narrow band imaging findings in gastroesophageal reflux disease: a pilot study

Standard endoscopy is an insensitive test for gastroesophageal reflux disease (GERD). Narrow band imaging (NBI) endoscopy enhances visualization of the distal esophagus. NBI patterns like intrapapillary capillary loop (IPCL) dilatation, tortuosity, and increased number; microerosions; increased vascularity at the squamocolumnar junction (SCJ); ridge-villous pattern below the SCJ; and presence of columnar islands in the distal esophagus have been suggested as features of GERD. We evaluated the effect of proton pump inhibitor (PPI) therapy on NBI findings in GERD patients. Patients prospectively underwent NBI upper endoscopy before and after PPI therapy. NBI findings were recorded at each endoscopy. Twenty-one patients with GERD symptoms (mean age 60.0 years; males 90.5%; white 90.5%) were studied. After PPI therapy, there was a significant reduction in the proportion of patients with the following NBI features: IPCL tortuosity (90% vs. 4.8%, P < 0.0001), dilated IPCLs (86% vs. 9.5%, P < 0.0001), and increased vascularity at the SCJ (43% vs. 9.5%, P= 0.0082). PPI led to healing of all microerosions (71% vs. 0%, P < 0.0001) and disappearance of ridge-villous patterns below the SCJ (14% vs. 0%, P < 0.0001). There was no significant change in the proportion of patients with increased numbers of IPCLs pre- and post-PPI therapy (71% vs. 48%, P= 0.09) or columnar islands in the distal esophagus (38% vs. 29%, P= 0.31). In patients with GERD symptoms, NBI features suggestive of GERD respond to PPI; suggesting these features are truly acid-mediated. These findings need to be confirmed by randomized controlled trials.