X0101 EFFECT 33 LIVE 2008-08-15 0000950137-08-009026 485APOS 0000826732 CALAMOS INVESTMENT TRUST/IL 033-19228 S000022429 Calamos Evolving World Growth Fund C000064540 Class R S000022429 Calamos Evolving World Growth Fund C000064541 Class A S000022429 Calamos Evolving World Growth Fund C000064542 Class B S000022429 Calamos Evolving World Growth Fund C000064543 Class C S000022429 Calamos Evolving World Growth Fund C000064544 Class I