Study ID	Treatment	Clinical improvement
Backonja 2008	(1) Capsaicin patch 8%, n = 206 (2) Control patch, n = 196	Over 2 to 12 weeks ≥ 30% pain reduction from baseline: (1) 91/206, (2) 69/196 (Participants with ≥ 50% pain reduction from baseline ‐ no significant difference between groups) ≥ 2 points reduction in pain from baseline: (1) 87/206, (2) 55/196 At 12 weeks PGIC (slightly/much/very much improved): (1) 114/206, (2) 85/196 Over 2 to 8 weeks ≥ 30% pain reduction from baseline: (1) 87/206, (2) 63/196 ≥ 2 points reduction in pain from baseline: (1) 82/206, (2) 51/196 At 8 weeks PGIC (slightly/much/very much improved): (1) 109/206, (2) 83/196
Bischoff 2014	(1) Capsaicin patch 8% 60 min, n = 24 (23 treated) (2) Placebo patch 60 min, n = 22	No responder outcomes reported. No significant difference in the summed pain intensity difference (from baseline) between groups at 4, 8, or 12 weeks after treatment in completers
Clifford 2012	(1) Capsaicin patch 8% 30 min, n = 167 (2) Capsaicin patch 8% 60 min, n = 165 (3) Control patch 30 min, n = 73 (4) Control patch 60 min, n = 89	Over 2 to 12 weeks ≥ 30% pain reduction from baseline: (1) 65/167, (2) 79/165, (3) 19/73, (4) 40/89 At 12 weeks PGIC (slightly, much, very much improved): (1) 109/167, (2) 114/165, (3) 33/73, (4) 56/89
Irving 2011	(1) Capsaicin patch 8%, n = 212 (2) Control patch, n = 204	At 12 weeks ≥ 50% pain reduction from baseline: (1) 64/212, (2) 43/204 ≥ 30% pain reduction from baseline: (1) 100/212, (2) 71/204 At 12 weeks PGIC (much and very much improved): (1) 83/212, (2) 50/204 ≥ 2 points reduction in pain from baseline: (1) 91/212, (2) 59/204 Over 2 to 8 weeks ≥ 50% pain reduction from baseline: (1) 61/212, (2) 41/204 ≥ 30% pain reduction from baseline: (1) 98/212, (2) 69/204 At 8 weeks PGIC (much and very much improved): (1) 71/212, (2) 49/204 ≥ 2 points reduction in pain from baseline: (1) 89/212, (2) 53/204
Simpson 2008	(1) Capsaicin patch 8% 30 min, n = 72 (2) Capsaicin patch 8% 60 min, n = 78 (3) Capsaicin patch 8% 90 min, n = 75 (4) Control patch, n = 82	Over 2 to 12 weeks ≥ 30% pain reduction from baseline: (1) 30/72, (2) 19/78, (3) 27/75, (4) 15/82 (capsaicin combined 76/225) At 12 weeks PGIC (much and very much improved): (1) 23/72, (2) 18/78, (3) 20/75, (4) 9/82 (capsaicin combined 61/225)
STEP 2014	(1) Capsaicin patch 8%, 30 min, n = 186 (2) Placebo patch, n = 183	Over 2 to 8 weeks ≥ 50% pain reduction from baseline: (1) 39/186, (2) 33/183 ≥ 30% pain reduction from baseline: (1) 74/186, (2) 60/183 At 8 weeks PGIC (much and very much improved), using ITT denominators: (1) 71/186, (2) 52/183 Over 2 to 12 weeks ≥ 50% pain reduction from baseline: (1) 41/186, (2) 35/183 ≥ 30% pain reduction from baseline: (1) 76/186, (2) 58/183 At 12 weeks PGIC (much and very much improved), using ITT denominators: (1) 68/186, (2) 51/183
Webster 2010a	(1) Capsaicin patch 8% 30 min, n = 72 (2) Capsaicin patch 8% 60 min, n = 77 (3) Capsaicin patch 8% 90 min, n = 73 (4) Control patch, 30, 60, 90 min pooled for analysis, n = 77	Over 2 to 8 weeks ≥ 50% pain reduction from baseline: (1) 17/72, (2) 21/77, (3) 17/73, (4) 8/77 ≥ 30% pain reduction from baseline: (1) 27/72, (2) 27/77, (3) 29/73, (4) 22/77 At 12 weeks PGIC (slight, much and very much improved): (1+2+3) 122/222 (capsaicin combined), (4) 32/77
Webster 2010b	(1) Capsaicin patch 8%, n = 102 (2) Control patch, n = 53	Over 2 to 12 weeks ≥ 50% pain reduction from baseline: (1) 40/102, (2) 19/53 ≥ 30% pain reduction from baseline: (1) 50/102, (2) 26/53 At 12 weeks PGIC (much and very much improved): (1) 41/102, (2) 15/53 Over 2 to 8 weeks ≥ 50% pain reduction from baseline: (1) 37/102, (2) 19/53 ≥ 30% pain reduction from baseline: (1) 50/102, (2) 24/53 At 8 weeks PGIC (much and very much improved): (1) 43/102, (2) 14/53
ITT: intention‐to‐treat; min: minute; n: number of participants in treatment arm; PGIC: Patient Global Impression of Change.