(Reuters) - CVC Capital Partners [CVC.UL] and other private equity owners are exploring options for generic drugmaker Alvogen, including a sale, which could be valued at about $4 billion, Bloomberg reported on Tuesday.

Alvogen's controlling shareholders have held talks with Shanghai Pharmaceuticals Holding Co for the sale of Alvogen's U.S. business, Bloomberg said, citing people familiar with the matter. bloom.bg/2ypxMEx

The drugmaker will keeps its Asian and central European operations, Bloomberg reported.

According to the report, Alvogen’s owners may also have talks with other international buyers.

European private equity fund CVC and Singaporean sovereign wealth fund Temasek had bought a controlling stake in Alvogen in 2015. reut.rs/2xuyXFY

Shanghai Pharmaceuticals was earlier planning to tie up with a consortium to make an offer for German generics drugmaker Stada Arzneimittel, which fell apart in May.

A CVC spokesman declined to comment. Alvogen was not immediately available for comment. Reuters was unable to immediately reach Shanghai Pharma for comment.