H4 to H1-B Transfer

[Vikramdce]

Hi All,

I am working in H1-B visa in USA and My wife currently has H1-B visa from her company in India

Her Visa is stamped and valid till Sept 2015 ( She has never travelled to USA before her visa got stamped in Oct 2014 )

Her current employer is not providing her any opporunity even though her Visa is stamped
can she come to USA in H4 Visa then search job and convert the H4 to H1-B or she has to file for new H1-B again after coming to USA ?

Please suggest


Thanks
Vikram