Ranbaxy shares gained 5.1 per cent to hit an all-time high in the trading session on Wednesday ahead of the company's merger with Sun Pharmaceutical Industries.
Trading in Ranbaxy shares will be suspended from April 6 due to amalgamation with Sun Pharmaceutical Industries.
On similar lines, stocks of Sun Pharmaceutical Industries gained 4.3 per cent.
Morgan Stanley said Sun Pharma is preparing for the transition to the next level.
Generic Nexium and hydroxychloroquine by Ranbaxy and Elepsia and Latanoprost drug by Sun Pharma unit Sun Pharma Advanced Research Co may provide good upside, it further said.
The investment bank maintained Sun Pharma among its best ideas and raised the target to Rs 1,241 from Rs 995.