PFIZER, THE world's largest drugmaker, is ending early-stage development of treatments for a range of illnesses, from obesity to heart disease, to focus on more profitable diseases.

The changes will not affect drugs in the last of three stages of testing needed for US approval, including the anti-clot drug Apixaban being developed with Bristol-Myers Squibb, Pfizer said in a memo to employees.

Development will end on at least 11 drugs, including six for obesity and heart disease and three for digestive disorders.

Chief executive Jeffrey Kindler said earlier this year that the New York-based company would focus its $8 billion (€5.69 billion) research budget on cancer, pain, Alzheimer's disease and diabetes.

Pfizer's cholesterol pill, Lipitor, the world's best-selling drug with $12.7 billion in 2007 revenue, is set to lose patent protection in 2011.

Products for cancer and pain are typically more profitable because the makers can charge a higher price and there is less competition. "Alzheimer's disease, diabetes, inflammation/immunology, oncology, pain and psychoses [schizophrenia] are confirmed as our higher priority areas," the company said. "These large markets, with rapidly advancing science, are the areas where Pfizer can take a leading position."

Mr Kindler said Pfizer would consider more acquisitions to fill its pipeline of experimental medicines. Analysts said yesterday the company may consider buying ImClone Systems, the New York maker of cancer drug Erbitux.

ImClone has said it received a $70-a-share bid from a large drugmaker it would not identify.

The memo said Pfizer would also stop early-stage research in anaemia, bone health, liver disease, muscle and some osteoarthritis compounds.

About 20 per cent of its research funding goes towards cancer. The restructuring would not result in facility closures and many employees would be shifted to other areas of research, it said.

Pfizer employs about 2,300 people in Cork and Dublin. - ( Bloomberg)