A large annuity manufacturer has changed the investment portfolios available with its variable annuities.

Jackson National Life Insurance Company, Lansing, Mich., a unit of Prudential P.L.C., London, says it has added a number of new investment options managed by well-known outside advisors.

The company also has upgraded the joint option on 2 of its guaranteed minimum withdrawal benefits and made those benefits available to members of employer-sponsored retirement plans that use Jackson National variable annuities as funding vehicles.

The company has added a 5% premium credit option for premium payments received during the first contract year.