Sales of blockbuster cholesterol and impotence drugs helped boost Pfizer's profits 30 per cent in the second quarter, the world's biggest drug producer said yesterday, meeting Wall Street expectations.

But Pfizer - which employs about 1,500 people in Cork and Dublin - gave a coded warning about one of the most promising new drugs in its pipeline, saying it may delay seeking US approval for its experimental inhaled insulin medicine, Exubera, amid concerns about safety and long-term effectiveness.

New York-based Pfizer, which merged with drug giant Warner-Lambert last summer, said it earned $1.89 billion, or 30 cents per share, compared with $1.44 billion, or 23 cents per share in the year-ago quarter.

Analysts expected the company to earn 29 cents to 31 cents per share, with an average estimate of 29 cents, according to research firm Thomson Financial/First Call.