The primary objective of the Phase 3 AFFIRM study is to evaluate the effect of a one-time intracoronary infusion of the Generx product candidate [Ad5FGF-4] on the change from baseline to Month 6 in Exercise Tolerance Test (ETT) duration. The patient population consists of individuals with refractory angina (CCS Class III or IV), who are no longer responsive to maximally tolerated medical therapy for angina, who are not candidates for standard mechanical interventions (stents and bypass surgery), and who have angina-limited exercise capacity.