BUDAPEST, Jan 20 (Reuters) - Hungarian drug maker Richter and its partner Actavis on Tuesday said a Phase III trial had positive results in anti-psychotic drug Cariprazine's effects to prevent relapse for schizophrenia patients.

Treatment with Cariprazine was associated with a 55 percent reduction in the risk of relapse versus placebo, the companies said in a statement posted on the Budapest Stock Exchange web site.

(Reporting by Marton Dunai; editing by Jason Neely)