An apparatus and associated method for forming a filter rod member of a smoking article, such as a cigarette, is provided. The apparatus comprises a rod-forming unit configured to form a continuous supply of a filter material into a continuous cylindrical rod member. An insertion unit is configured to insert an adsorbent material carried by a carrier material into the rod member. The method comprises forming a continuous supply of a filter material into a continuous cylindrical rod member, and inserting an adsorbent material carried by a carrier material into the rod member such that the adsorbent material is disposed within the rod member.