CHICAGO, Dec 24 (Reuters) - Chinese vaccine maker Sinovac Biotech Ltd (SVA.A: Quote, Profile, Research) said on Monday its vaccine for the H5N1 strain of bird flu produced positive results in a Phase II study that assessed its ability to produce an immune response. Preliminary results from a clinical trial of the H5N1 whole viron vaccine, conducted by Beijing Centers for Disease Control and Prevention, showed varying degrees of immune response in three different doses, Sinovac said.

The vaccine produced no serious adverse reactions among the 402 volunteers, who ranged in age from 18 to 60, the company said.

Another study, a Phase I clinical trial of the split H5N1 vaccine, found that version of the vaccine was safe for use in children, adults and the elderly, Sinovac said.

(Reporting by Susan Kelly, editing by Maureen Bavdek)