The present disclosure provides a polyolefin-based composition made from or containing (A) a first grafted polyolefin composition, (B) a second grafted polyolefin composition made from or containing a first metallocene-catalyzed linear low density polyethylene grafted with an unsaturated monomer, (C) a second metallocene-catalyzed linear low density polyethylene composition, (D) a Ziegler-Natta-catalyzed linear low density polyethylene composition, (E) an elastomeric composition made from or containing (i) an elastomeric ethylene copolymer and (ii) an ethylene-propylene elastomer, and (F) a tackifier composition. Optionally, the polyolefin-based composition may be further made from or contain an additives composition. The polymeric composition is suitable for use as a tie-layer adhesive composition.