The Serum Institute of India (SII) on Saturday broke its silence over the pricing of its Covid-19 vaccine 'Covishield' and said that it is the most affordable vaccine available in the market today.SII, which manufactures the AstraZeneca vaccine Covishield at its Pune facility, said that the initial prices were kept very low globally as it was based on advance funding given by the countries for at-risk vaccine manufacturing.The initial supply price of the vaccine for all government immunisation programmes, including in India, was the lowest, it said."The price of the vaccine is still lower than a lot of other medical treatment and essentials required to treat Covid-19 and other life-threatening diseases," Adar C. Poonawalla, Chief Executive Officer, SII, said in a statement.The company also said that only a limited portion of Sll's volume will be sold to private hospitals at Rs 600 per dose.Earlier this week, the company had announced that Covishield will be sold at Rs 400 per dose to the state governments and Rs 600 to the private hospitals.The Indian biotechnology and pharmaceuticals company announced the new prices after the government allowed vaccination for all persons above the age of 18 years from May 1 onwards.