The vote, originally due to take place on Wednesday, was delayed to give shareholders more time to consider the increased offer from Santiago-based CFR.
CFR last week raised its takeover bid for South Africa's second-largest drug maker by 1.6 percent to 12.8 billion rand in cash and stock, in an attempt to win over
Adcock's top shareholder, the state-run pension fund.
The fate of the rare Chile-South Africa tie-up is in doubt because the state-owned Public Investment Corporation, which owns about 19 per cent of Adcock, has rejected CFR's sweetened bid saying it wants all cash.
CFR, in turn, has accused the fund of protectionism.
CFR's attempt to enter fast-growing Africa is also jeopardised by a rival offer from South African conglomerate Bidvest, which has gone straight to shareholders with a cash bid for nearly a third of Adcock.
CFR needs approval from shareholders holding 75 per cent of
Adcock for the deal to go through. More than 68 per cent of shareholders voting at a meeting in suburban Johannesburg on Wednesday agreed to the postponement.
The vote is now likely to be held around the end of January, Adcock and CFR have said.