COBRA PZF™ Coronary Stent for Early Healing, Thrombus Inhibition, Endothelialization and Avoiding Long-Term DAPT

TVF defined as cardiac death, target vessel myocardial infarction (MI \[Q wave or non-Q wave, ARC definition\], or clinically driven target vessel revascularization (TVR) by percutaneous or surgical methods within 270 days post-procedure.

Time frame: 270 days

Death from any cause

Time frame: 30 days

Death from any cause

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death from any cause

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death from any cause

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death from any cause

Time frame: 1800 days

Population: The denominator is comprised of all the patients who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Angiographic subset included 115 of the 296 enrolled. Therefore, the overall number of participants analyzed for this outcome measure is 115.

Time frame: 270 days

Population: Angiographic subset of patients

Bleeding Complications: Procedure-related hemorrhagic event that requires a transfusion and/or surgical intervention Vascular Complications: May include pseudo aneurysm, arteriovenous fistula (AVF), peripheral ischemia/nerve injury, and vascular event requiring transfusion or surgical repair

Time frame: 30 days

Composite Endpoint of Cardiac Death or MI (ARC definition)

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Composite Endpoint of Cardiac Death or MI (ARC definition)

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Composite Endpoint of Cardiac Death or MI (ARC definition)

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Composite Endpoint of Cardiac Death and MI (ARC definition)

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death due to any of the following: Acute myocardial infarction Cardiac perforation/pericardial tamponade Arrhythmia or conduction abnormality Cerebrovascular accident within 30 days of the procedure or cerebrovascular accident suspected of being related to the procedure Death due to complication of a cardiac procedure including bleeding, vascular repair, transfusion reaction, or bypass surgery Any death is which a cardiac cause cannot be excluded

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death due to any of the following: Acute myocardial infarction Cardiac perforation/pericardial tamponade Arrhythmia or conduction abnormality Cerebrovascular accident within 30 days of the procedure or cerebrovascular accident suspected of being related to the procedure Death due to complication of a cardiac procedure including bleeding, vascular repair, transfusion reaction, or bypass surgery Any death is which a cardiac cause cannot be excluded

Time frame: 30 days

Death due to any of the following: Acute myocardial infarction Cardiac perforation/pericardial tamponade Arrhythmia or conduction abnormality Cerebrovascular accident within 30 days of the procedure or cerebrovascular accident suspected of being related to the procedure Death due to complication of a cardiac procedure including bleeding, vascular repair, transfusion reaction, or bypass surgery Any death is which a cardiac cause cannot be excluded

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Death due to any of the following: Acute myocardial infarction Cardiac perforation/pericardial tamponade Arrhythmia or conduction abnormality Cerebrovascular accident within 30 days of the procedure or cerebrovascular accident suspected of being related to the procedure Death due to complication of a cardiac procedure including bleeding, vascular repair, transfusion reaction, or bypass surgery Any death is which a cardiac cause cannot be excluded

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

Death due to any of the following: Acute myocardial infarction Cardiac perforation/pericardial tamponade Arrhythmia or conduction abnormality Cerebrovascular accident within 30 days of the procedure or cerebrovascular accident suspected of being related to the procedure Death due to complication of a cardiac procedure including bleeding, vascular repair, transfusion reaction, or bypass surgery Any death is which a cardiac cause cannot be excluded

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

Defined as a percutaneous intervention or surgical bypass of any segment of the target vessel associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis \>= 50% by QCA, or revascularization of a target vessel with diameter stenosis \>=70% by QCA without either angina or a positive functional study.

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention or surgical bypass of any segment of the target vessel associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis \>= 50% by QCA, or revascularization of a target vessel with diameter stenosis \>=70% by QCA without either angina or a positive functional study.

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention or surgical bypass of any segment of the target vessel associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis \>= 50% by QCA, or revascularization of a target vessel with diameter stenosis \>=70% by QCA without either angina or a positive functional study.

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention or surgical bypass of any segment of the target vessel associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis \>= 50% by QCA, or revascularization of a target vessel with diameter stenosis \>=70% by QCA without either angina or a positive functional study.

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as a percutaneous intervention of the target lesion or bypass surgery of the target vessel performed for restenosis or other complication of the target lesion associated with positive functional ischemia study or ischemic symptoms AND an angiographic minimal lumen diameter stenosis of \>= 50% by QCA, or revascularization of a target vessel with a diameter stenosis of \>=70% by QCA without either angina or a positive functional study.

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

Attainment of \<30% final residual stenosis of the target lesion using only the COBRA PzF Coronary Stent System

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Early Stent Thrombosis (ARC Definition) 0-30 days post index procedure

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Relative changes that occur in the percent diameter stenosis of the segment and are provided by the following relationship: % diameter stenosis= (1-\[MLD/Reference diameter\]) x 100

Time frame: 270 days

Population: Angiographic subset included 115 of the 296 enrolled. Therefore, only 115 participants analyzed.

* In-stent and in-Segment minimal lumen diameter obtained immediately after stent implantation and at angiographic assessment at 270 days. * In-stent or in-segment late loss was defined as the difference between minimum lumen diameter (in-stent or in-segment) immediately after implantation and that obtained at angiographic follow-up at 270 days.

Time frame: 270 days

Population: Angiographic subset included 115 of the 296 enrolled. Therefore, the overall number of participants analyzed for this outcome measure is 115.

in-stent neointimal thickness assessed by Optical Coherence Tomography

Time frame: 270 days

Population: OCT subset included 57 of the 296 enrolled. Therefore, the overall number of participants analyzed for this outcome measure is 57.

Stent Thrombosis after 30 days and on or before 360 days

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Stent Thrombosis after 30 days and on or before 270 days

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Stent Thrombosis after 30 days and on or before 180 days

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Attainment of \<30% final residual stenosis of the target lesion using any percutaneous method

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Optical Coherence Tomography assessment of the lumen and stent area after the clinical follow up at 270 days

Time frame: 270 days

Population: OCT subset included only 57 of the 296 participants enrolled. Therefore, only 57 participants analyzed.

Optical Coherence Tomography assessment of the lumen and stent volume after the clinical follow up at 270 days

Time frame: 270 days

Population: OCT subset includes 57 of the 296 enrolled. Therefore, only 57 participants analyzed.

Cardiac death, MI (Q wave and non-Q wave), emergent bypass surgery, or clinically driven target lesion revascularization (TLR) by percutaneous or surgical methods

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Cardiac death, MI (Q wave and non-Q wave), emergent bypass surgery, or clinically driven target lesion revascularization (TLR) by percutaneous or surgical methods

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

Cardiac death, MI (Q wave and non-Q wave), emergent bypass surgery, or clinically driven target lesion revascularization (TLR) by percutaneous or surgical methods

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Cardiac death, MI (Q wave and non-Q wave), emergent bypass surgery, or clinically driven target lesion revascularization (TLR) by percutaneous or surgical methods

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Cardiac death, MI (Q wave and non-Q wave), emergent bypass surgery, or clinically driven target lesion revascularization (TLR) by percutaneous or surgical methods

Time frame: 30 days

Defined as either a Q wave MI (QWMI) or Non-Q wave MI (NQMI). QWMI is defined as development of new, pathological Q waves in 2 or more contiguous leads (as assessed by the Clinical Events Committee) with post-procedure CK-MB levels elevated above normal. NQWMI is defined as any elevation of post-procedure CK-MB to \>=3 times site normal in the absence of pathological Q waves

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as either a Q wave MI (QWMI) or Non-Q wave MI (NQMI). QWMI is defined as development of new, pathological Q waves in 2 or more contiguous leads (as assessed by the Clinical Events Committee) with post-procedure CK-MB levels elevated above normal. NQWMI is defined as any elevation of post-procedure CK-MB to \>=3 times site normal in the absence of pathological Q waves

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as either a Q wave MI (QWMI) or Non-Q wave MI (NQMI). QWMI is defined as development of new, pathological Q waves in 2 or more contiguous leads (as assessed by the Clinical Events Committee) with post-procedure CK-MB levels elevated above normal. NQWMI is defined as any elevation of post-procedure CK-MB to \>=3 times site normal in the absence of pathological Q waves

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as either a Q wave MI (QWMI) or Non-Q wave MI (NQMI). QWMI is defined as development of new, pathological Q waves in 2 or more contiguous leads (as assessed by the Clinical Events Committee) with post-procedure CK-MB levels elevated above normal. NQWMI is defined as any elevation of post-procedure CK-MB to \>=3 times site normal in the absence of pathological Q waves (historical definition). ARC definition includes Troponin or CK-MB \>3 x UNL

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as either a Q wave MI (QWMI) or Non-Q wave MI (NQMI). QWMI is defined as development of new, pathological Q waves in 2 or more contiguous leads (as assessed by the Clinical Events Committee) with post-procedure CK-MB levels elevated above normal. NQWMI is defined as any elevation of post-procedure CK-MB to \>=3 times site normal in the absence of pathological Q waves

Time frame: 1800 days

Population: KM analysis estimate for patients in the ITT population who had enough follow-up for 1800-days analysis (at least 1770 days allowing for 30 days window) or patients who had an event within 1800 days post-procedure and censoring those not reaching the endpoint or sufficient follow up.

This measure assess the average proportion of uncovered and or malapposed struts measured by Optical Coherence Tomography in participants

Time frame: 270 days

Population: OCT subset included 57 of the 296 enrolled. Therefore, the overall number of participants analyzed for this outcome measure is 57.

Attainment of \<30% final residual stenosis of the target lesion and no in-hospital MACE

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as sudden onset of vertigo, numbness, dysphasia, weakness, visual field defects, dysarthria or other focal neurological deficits due to vascular lesions of the brain such as hemorrhage, embolism, thrombosis, or rupturing aneurysm, that persists more than 24 hours.

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as sudden onset of vertigo, numbness, dysphasia, weakness, visual field defects, dysarthria or other focal neurological deficits due to vascular lesions of the brain such as hemorrhage, embolism, thrombosis, or rupturing aneurysm, that persists more than 24 hours.

Time frame: 30 days

Population: The denominator is comprised of all the patients who had enough follow-up for 30-days analysis (at least 23 days allowing for 7 days window) or patients who had an event within 30 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as sudden onset of vertigo, numbness, dysphasia, weakness, visual field defects, dysarthria or other focal neurological deficits due to vascular lesions of the brain such as hemorrhage, embolism, thrombosis, or rupturing aneurysm, that persists more than 24 hours.

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

Defined as sudden onset of vertigo, numbness, dysphasia, weakness, visual field defects, dysarthria or other focal neurological deficits due to vascular lesions of the brain such as hemorrhage, embolism, thrombosis, or rupturing aneurysm, that persists more than 24 hours.

Time frame: 270 days

Population: The denominator is comprised of all the patients who had enough follow-up for 270-days analysis (at least 240 days allowing for 30 days window) or patients who had an event within 270 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

TVF defined as cardiac death, target vessel myocardial infarction (MI) \[Q wave or non-Q wave, ARC definition\], or clinically driven target vessel revascularization (TVR) by percutaneous or surgical methods.

Time frame: 180 days

Population: The denominator is comprised of all the patients who had enough follow-up for 180-days analysis (at least 150 days allowing for 30 days window) or patients who had an event within 180 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.

TVF defined as cardiac death, target vessel myocardial infarction (MI) \[Q wave or non-Q wave, ARC definition\], or clinically driven target vessel revascularization (TVR) by percutaneous or surgical methods.

Time frame: 30 days

TVF defined as cardiac death, target vessel myocardial infarction (MI) \[Q wave or non-Q wave, ARC definition\], or clinically driven target vessel revascularization (TVR) by percutaneous or surgical methods.

Time frame: 360 days

Population: The denominator is comprised of all the patients who had enough follow-up for 360-days analysis (at least 330 days allowing for 30 days window) or patients who had an event within 360 days post-procedure. The number of events varies for each of the endpoints resulting in different denominators.