Siemens-backed ViewRay has postponed a $64m initial public offering that would have been used to help commercialise its radiation therapy system.

ViewRay, a US-based radiation therapy technology developer backed by industrial equipment maker Siemens, has postponed its initial public offering on Nasdaq.

The company did not reveal an updated timeline for the flotation or stated a reason for the move in the SEC filing revealing the postponement. ViewRay filed for a $69m IPO in February 2015 but subsequently revised the figure down to $64.4m the following month.

ViewRay markets an MRI-guided radiation therapy system dubbed MRIdian that simultaneously produces images of…