Product: M K -3475/I N C B024360 2 Protocol/ A mend ment No.: 669-04/E C H O-304-04 MS D Signatory Typed Na me: D at e Titl e: Protocol -specific MS D c ontact infor mation can be found in the Investigator Trial File Bi n der (or e q uivale nt). Investigator Signatory I a gr e e t o c o n d u ct t his cli ni c al tri al i n a c c or d a n c e wit h t h e d esi g n o utli n e d i n t his pr ot o c ol a n d t o a bi d e b y all pr o visi o ns of t his pr ot o c ol. Typed Na me: D at e Titl e: M K -3475-669-04 (I N C B 24360-304-04) Final Protocol 12-Jun-2018 C o nfi d e nti al 0 4 Y B M H Product: M K -3475/I N C B024360 3 Protocol/ A mend ment No.: 669-04/E C H O-304-04 PROTOCOL A MEND MENT SU M MARY OF CHANGES A mend ment04 Overall Rationale for the A mend ment: The external data monitoring co m mittee ( eD M C) anal ysis ofthe K E Y N O T E -252/ E C H O-301blinded clinical study, a Phase 3 study e v al u ati n g e p a c a d ost at i n c o m bi n ati o n wit h p e m br oli z u m a b i n p arti ci p a nts wit h u nr es e ct a bl e or m et ast ati c m el a n o m a, d et er mi n e d t h at the study did not meet the pre-specified endpoint of i mprove ment in progression-free survival for the co mbination of pe mbrolizu mab and epacadostat co mpared to pe mbrolizu mab and placebo. The e D M C further deter mined that the overall survival endpoint is not e x p e ct e d t o r e a c h st atisti c al si g nifi c a n c e. T h es e r es ults ar e s p e cifi c t o m el a n o m a, a n d c a n n ot b e e xtr a p ol at e d t o ot h er t u m or t yp es. Of note there were no ne w safety concerns with the pe mbrolizu mab + epacadostat co mbination co mpared to pe mbrolizu mab monotherap y. Given that there is no confir med lack of efficacy of pe mbrolizu mab + epacadostat in other tu mor types, the Spon sor and MS D consider interruption of study treat ment unnecessaryin K E Y N O T E-669/ E C H O-304. Enroll ment in this studywas per manently stopped on 02-M A Y -2018 as a strategic decision. For participants who are considered to be obtaining ongoing clinical b e n efit, c o nti n u e d st u d y t r e at m e nt will b e at t h e dis cr eti o n of t h e in v esti g at or, aft er a dis c ussi o n wit h t h e p arti ci p a nt of t h e o bs er v e d results fro mKE Y N OTE- 252/EC H O-301. Su m mary of Changes Table: Section # and Na me Description of Change Brief Rationale 1 S y n o psis A d diti o n of n ot es t o cl arif y t h at aft er t h e first Given the lat est results for pe mbrolizu mab plus 2. S c h e d ul e of A cti viti es i magingassess ment for efficacy analysis, epacadostat treat ment fro m melano ma study E C H O- (S o A ) participants may choose to discontinue fro m the 301/ KE Y N OTE-252, as of 02-M A Y -2018 enroll ment st u d y or c o nti n u e st u dy tr e at m e nt as p er pr ot o c ol was per manently stoppedin KE Y N OTE-669/EC H O- aft er p arti ci p a nt dis c ussi o n wit h t h e i n v esti g at or . 304. 89 participants were rando mized into the study. P arti ci p a nts will b e gi v e n t h e o pti o n t o dis c o nti n u e fr o m t h e st u d y or c o nti n u e st u d y tr e at m e nt. T h e st u d y will r e m ai n o p e n t o all o w p arti ci p a nts a c c ess t o st u d y tr e at m e nt a n d t o all o w c oll e cti o n of pr eli mi n ar y efficacy data in thisH NS C C indication. E fficacy procedures after Week 9are no longer being m a n d at e d . M K -3475-669-04 (I N C B 24360-304-04) Final Protocol 12-Jun-2018 0 4 Y B M H C o nfi d e nti al Product: M K -3475/I N C B024360 4 Protocol/ A mend ment No.: 669-04/E C H O-304-04 Section # and Na me Description of Change Brief Rationale W h er e d el eti o n of t e xt c o ul d c a us e c o nf usi o n, d u e t o t h e d esi g n of t h e st u d y t o d at e, t h e t e xt h as b e e n l eft unchanged and a note has been added. 3. 2. 3 O n g oi n g Cli ni c al KE Y N OTE 252/E C H O-301 related text inserted. St u di es I ns erte d n ot e t h at e nr oll m e nt w as st o p p e d; aft er 5. 1 O v er all D esi g n the first i maging assess ment at Week 9(± 7 d a y s), p arti ci p a nts h a v e t h e o pti o n t o c o nti n u e o n t h e s t u d y aft er p arti ci p a nt dis c ussi o n wit h t h e i n vesti g at or, all st u d y effi c a c y pr o c e d ur es will st o p aft er W e e k 9 a n d t h er e aft er will b e perfor med as per local standard of care (So C ). Clarified safet y procedures for Groups 1, 2, and 3. 1. Synopsis Addition of text statingthatas of 02-M A Y -2018 5.2 Nu mber of enroll ment was stopped and 89 participants were P arti ci p a nts e nr oll e d i n t h e st u d y. 7.2.6 Second Course A d diti o n of n ot e, a n d r el at e d c h a n g es, t h at P h as e i maging assess ments will no longer be made by 7. 4 Bli n di n g bli n d e d i n d e p e n d e nt c e ntr al r e vi e w ( BI C R); all disease progression will be assessed by the investigator based on R E CIS T 1.1. 1. Synopsis Re moved references to BI C R assess ment of 2. S c h e d ul e of A cti viti es disease progression. (S o A) 4. O bj e cti v es/ H y p ot h es es and Endpoints 5. 1 O v er all D esi g n 5. 4. 1 R ati o n al e f or E n d p oi nts M K -3475-669-04 (I N C B 24360-304-04) Final Protocol 12-Jun-2018 0 4 Y B M H C o nfi d e nti al Product: M K -3475/I N C B024360 5 Protocol/ A mend ment No.: 669-04/E C H O-304-04 Section # and Na me Description of Change Brief Rationale 8. 1 Dis c o nti n u ati o n of Study Treat ment 9. 1. 9. 1. 3 Gr o u p 3 E XTRE ME Regi ment Dose Ad ministrations 9.