Which of the following modifications differentiate tenecteplase from alteplase?

Tenecteplase differentiates from alteplase due to point mutations that significantly enhance its pharmacological properties. These mutations lead to changes in the amino acid sequence of the protein, which in turn alters its structure and function. Specifically, the modifications allow tenecteplase to have a longer half-life, greater specificity for fibrin, and increased resistance to inhibition by plasminogen activator inhibitor-1 (PAI-1). As a result, tenecteplase can provide more effective thrombolysis in certain clinical settings, such as ST-segment elevation myocardial infarction (STEMI), with the advantage of being administered as a single bolus injection. This differentiation underscores the importance of minor genetic modifications in enhancing therapeutic efficacy and convenience in drug administration.