UPDATE 1-Australia's Sigma/Metcash mull joint Symbion bid

(Adds CEO comments, shares)

SYDNEY, April 22 (Reuters) - Australia's Sigma Pharmaceuticals Ltd (SIP.AX: Quote, Profile, Research, Stock Buzz) and grocery wholesaler Metcash Ltd (MTS.AX: Quote, Profile, Research, Stock Buzz) are in talks over a joint bid for assets being sold by Primary Health Care Ltd (PRY.AX: Quote, Profile, Research, Stock Buzz), both companies said on Tuesday.

After its A$2.7 billion takeover of Symbion Health Ltd SYB.AX ended a year-long battle for control, Primary wants to sell the Symbion pharmacy and consumer business which private equity groups had earlier offered around A$1 billion ($943 million) for.

"Metcash and Sigma are investigating the possibility of jointly bidding for Symbion's consumer brands and pharmaceutical wholesaling assets," Metcash Chief Executive Andrew Reitzer said.

"The pharmaceutical industry's characteristics have changed since we last examined its opportunities, making it more attractive," he said.

Primary, which has said it has received expressions of interest from international and domestic parties, is expected to start accepting formal bids in May.

Private equity firm Archer Capital has said it expressed interest in the whole business while Sigma only wants the consumer unit, which is Australia's largest distributor of vitamin supplements.

A tie-up with Metcash, which could take on the pharmacy unit, could allow it to better compete with bidders wanting to buy the lot.

"We've been discussing with various potential partners," Elmo de Alwis, managing director of Sigma Pharmaceuticals, told Reuters on Tuesday.