The antibiotics pharmaceutical maker Optimer Pharmaceuticals Inc has been the subject of interest from GlaxoSmithKline Plc and Astellas Pharma Inc of Japan. This comes after an increase in share values from the last four years.

The maker of Dificid the antibiotic can garner as much as US$1 billion during an auction. This was confirmed by anonymous sources as the discussions are private. Other possible suitors include Cubist Pharmaceuticals Inc and AstraZeneca Plc.

With the purchase of Optimer, these drugmakers would be generating more revenue in hospitals because Dificid is able to treat intestinal infections in patients confined in the hospitals. The Jersey City based drug company is attractive to other drug firms as it has an existing distribution network as well as utilize the purchaser's network to sell and deliver the product.

Share values of Optimer rose by 19% to US$13.91 per share, increasing the enterprise value of the firm to US$666 million.