RPL554 + tiotropium + olodaterol

A triple combination therapy consisting of **RPL554**, **tiotropium**, and **olodaterol** investigated for the treatment of Chronic Obstructive Pulmonary Disease (COPD). **RPL554** is an inhaled dual inhibitor of phosphodiesterase 3 (PDE3) and phosphodiesterase 4 (PDE4), developed for its anti-inflammatory and bronchodilatory effects. **Tiotropium** is a long-acting muscarinic antagonist (LAMA) that relaxes airway smooth muscle by blocking muscarinic M3 receptors, reducing cholinergic bronchoconstriction. **Olodaterol** is a long-acting beta2-adrenergic agonist (LABA) that activates beta2-adrenergic receptors, leading to bronchodilation via increased cAMP levels in airway smooth muscle cells. The combination is designed to provide additive or synergistic bronchodilation and anti-inflammatory effects for maintenance therapy in COPD patients[1][2][3][6][4].