Aetna Inc., health insurance major, is considering the sale of its pharmacy benefits management unit.

Sources close to the development informed that Medco Health Solutions Inc. and CVS Caremark Corp. are the forerunners in the race of potential buyers.

Prescription-drug programs are handled by pharmacy-benefit managers for pharmacies.

Price negotiations with pharmacies are also done by Pharmacy-benefit managers.

The industry of pharmacy-benefit has been in the process of consolidation.

It was also informed that Express Scripts Inc., which recently acquired NextRx pharmacy-benefits business by for 4.68 billion dollars, may also take interest in Aetna's pharmacy benefits management unit.

Aetna, which is the 3rd largest insurer in terms of members, had taken aback Wall Street in June by hacking its 2009 profit forecast.

As per analysts' April-estimates the sale of pharmacy-benefit business could fetch Aetna as much as 2 billion dollars.

However, Aetna could not be contacted for comment.