New Delhi, July 7 : The Union Health Ministry has asked all the states to strengthen their vigil so that black marketing of Covid-19 drug Remdesivir is prevented. The Directorate General of Health Services under the Health Ministry has written to the Drug Controllers of the states to prevent sale of Remdesivir above MRP. The Central Drugs Standard Control Organisation has given approval for the manufacturing and marketing of Remdesivir to Cipla, Hetro and Mylan. The DGHS said that it has received a letter from LocalCircles routed through the Health Ministry, raising concerns over black marketing and overpricing of Remdesivir by certain unscrupulous persons. "In view of the above, you are requested to instruct your enforcement officials to keep strict vigil on the matter to prevent black marketing and sale of Remdesivir injection above the MRP," the DGHS said in the letter to the states. /IANS