Mumbai: Ranga Iyer, managing director of the Mumbai-listed Wyeth Ltd, resigned on Monday after a board restructuring at the Indian arm of US drug maker Wyeth.

Moving on: Ranga Iyer, 56, who spent 29 years with Wyeth, says he hasn’t yet decided his next move. Ashesh Shah/Mint

However, Pfizer and Wyeth will continue to operate separately in India, a Pfizer spokesperson said in an emailed response on Monday.

“I haven’t yet decided my next move," said Iyer, 56, who spent 29 years with the firm and is vice-president of the Organisation of Pharmaceutical Producers of India, an industry body that represents foreign drug makers in India.

Wyeth’s shares on Monday declined 1.31% on the Bombay Stock Exchange to close at Rs745 each. The exchange’s benchmark Sensex index closed 0.42% down at 16,740.50 points. Wyeth holds a 57.15% stake in its Indian unit. Wyeth is the sixth largest pharmaceutical multinational firm in India by sales, with a revenue of Rs404 crore in the fiscal year ended 31 March.