ZURICH, Dec 27 (Reuters) - Swiss drugs regulator Swissmedic said on Monday it approved Ronapreve, an antibody treatment jointly developed by Roche and Regeneron (REGN.O), to treat COVID-19 patients. "In this procedure, no data on efficacy against the Omicron variant were submitted," Swissmedic said in a statement. The antibody treatment was already authorised for prescription in Switzerland under COVID-19 Ordinance 3 since April 15, Swissmedic said.