Mumbai, Nov 17 : The key Indian equity indices hit fresh record highs on Tuesday tracking a positive global trend after pharma giant Moderna announced that its vaccine has shown more than 94 per cent effectiveness in preliminary data from the company's ongoing study. Moderna on Monday said that its experimental vaccine is 94.5 per cent effective in preventing Covid-19, boosting hopes of the economy emerging from a year of pandemic-induced downturn. Sensex crossed the 44,000 mark and touched a record high of 44,161.16 points. Around 9.45 a.m., it was trading at 43,921.55, higher by 313.78 points or 0.65 per cent from its previous close of 43,637.98. Nifty50 was trading at 12,855.75, higher by 75.50 points or 0.59 per cent from its previous close. It has recorded an all-time high of 12,934.05 points. Healthy buying was witnessed in banking, finance and metal stocks. The top gainers on the Sensex so far were Tata Steel, IndusInd Bank and HDFC Bank. HCL Technologies, Bajaj Auto and Infosys were the major losers so far. The announcement by Moderna led to a rally in the US stock market on Monday. The announcement came just a week after Pfizer Inc had announced 90 per cent efficacy of its vaccine. Taken together, these two vaccines are firmly on course to seek emergency use authorisation from the US Food and Drug Administration if results hold out in the final study results due soon. /IANS