Pfizer, which posted $48 billion in revenue last year, could see severe erosion in sales in the coming years from patent expirations on its products including that of its blockbuster Lipitor cholesterol treatment.

The company inked a major deal valued at $68 billion with US rival Wyeth to help shore up profits and has also restructured its operating model around separate units – such as established products including its generic drugs and emerging markets. (See: Pfizer-Wyeth create $68-billion blockbuster deal) 

Pharma companies are increasingly turning their attention towards developing countries as the going gets tough for them in more established markets.

Without disclosing financial terms, Pfizer yesterday announced deals with Aurobindo Pharma Ltd and Claris Lifesciences Ltd that would help it substantially increase its offerings in medicines that have lost patent protection in markets around the world, a fortnight after it filed patent infringement suits against Aurbindo and other Indian generics producers to block them from marketing generic equivalents to its blockbuster pain management drug, Lyrica in US.

US rules for the sale of generic drugs, after the expiry of patent protection to the original manufacturer, allow the first-to-file to challenge the patent of the innovator drug 180 days of marketing exclusivity following the patent expiry. The innovator has to sue the generic company within 45 days of the challenge to get a 30-month stay on final marketing approval.

Other companies against which Pfizer has initiated action include Teva, Sandoz, Actavis, Cobalt Laboratories, Alphapharm Pty Ltd for Lyrica patent violations in US.

The latest Pfizer-Aurobindo deal expands on an existing collaboration between the companies that initiated a move into selling generic versions of other companies' medicines in the US and Europe, in a bid to add $1 billion to its revenue over four years from selling generic medicines.

In March 2009, Pfizer entered into multiple agreements with Aurobindo buying the rights to sell the Indian firm's 75 generic drugs as pills and 12 as injectables in the US and Europe, as part of expanding its 'established products business units' – an arm of the multinational drug firm which focuses on commercialisation of drugs whose market exclusivity and patents have expired.

Under the expanded deal, Pfizer would gain rights to 55 generic pills and five injectale products across 70 emerging markets in Latin America, Eastern Europe, Asia, Africa and the Middle East.

The medicines include anti-infectives, as also drugs for treatment of central nervous system disorders and cardiovascular disease.

According to Jean-Michel Halfon, president of Pizer's emerging markets unit, Halfon, the deal is in line with Pfizer's strategy to expand its presence in emerging markets. Halfon said Pfizer should reach the 2012 revenue goal by maintaining a 4 per cent market share in emerging markets.

The US drugmaker also gains US and European rights to a number of generic pills in the expanded Aurobindo deal. This adds to a larger clutch of medicines to which it gained rights following a deal announced in March with the Indian firm.

With the Claris agreement, Pfizer has acquired rights to 15 injectable generic medicines for pain, infections and other conditions.

Pfizer has prioritised licensing deals in a move to expand its injectables business, where it has relatively few rivals and maintains it has a competitive cost structure.

With the deals, Pfizer now holds rights to off-patent versions of 128 non-Pfizer drugs including 98 pills and 30 injectable medicines.

In the developed world, the drugmaker is planning a $1 billion addition by 2012 for its established products unit, which includes its off-patent medicines. With the deals, the company is looking to add products that will contribute to more than half of that revenue goal.

David Simmons, president of Pfizer's off-patent medicines said in an interview that the world of off-patent medicines is currently being poorly served

He added that the company was making a major drive in that direction to increase the portfolio of high quality products the company produces at affordable prices.