Table 1 All studies of SSRIs augmented by atypical anti-psychotic in OCD with their characteristics

McDougle, 2000 [12]

Risperidone (20)

1 - 6

6

12 (open label of a SSRI or clomipramine)

58.3% had at least 2 trials of SRIs

30% at least 1 trial

≤ 35% improvement or Y-BOCS ≥16 and no better than score of 3 (minimal improvement) on CGI to SSRI

Placebo (16)

(2.2, 0.7)

Hollander, 2003 [14]

Risperidone (10)

0.5 - 3

8

12 (routine care SSRI)

100% had at least 2 trials SRIs

62.5% at least 1 trial

No better than score of 3 (minimal improvement) on CGI to SSRI. No minimum severity on Y-BOCS specified

Placebo (6)

(2.25, 0.86)

Erzegovesi, 2005 [15]

Risperidone (10)

0.5

6

12 (open label fluvoxamine)

100% had at least 1 trial of a SRI

None

35% or greater improvement or Y-BOCS ≥16 and no better than score of 3 (minimal improvement) on CGI to SSRI

Placebo (10)

(fixed dose)

Simpson, 2013 [16]

Risperidone (20)

0.5 – 4

8

12 (routine care SSRI)

80% had at least 2 trials of SRIs

7% at least 1 trial

All but two had at least minimal improvement to a SSRI (i.e. some partial responders) and Y-BOCS ≥16

Placebo (40)

CBT (40)

Storch, 2013 [17]

Paliperidone (17)

3 - 9

8

12 (routine care SSRI)

100% had at least 2 trials

0% had at least 1 trial

Not formally assessed but “SSRI had had minimal effect”. Y-BOCS ≥19

Placebo (17)

Bystritsky, 2004 [18]

Olanzapine (13)

5 - 20

6

12 (routine care, SSRI)

100% had at least 2 trials

100% at least 1 trial

No specific criteria

Placebo (13)

(11.2, 6.5)

Shapira, 2004 [13]

Olanzapine (22)

5 - 10

6

8

40.9% had at least 1 trial of SRI

Not known

<25% improvement and score of 4 (moderate) or greater on CGI and Y-BOCS ≥16

Placebo (22)

(6.1, 2.1)

(open label fluoxetine)

Denys, 2004 [19]

Quetiapine (20)

200

8

8 (routine care SSRI)

100% had 2 or more trials

72.5% at least one trial

< 25% improvement on Y-BOCS to SSRI and Y-BOCS ≥18

Placebo (20)

(Range 100–300)

Carey, 2005 [20]

Quetiapine (20)

25 - 300

6

12 (routine care SSRI)

Not known

Not known

< 25% improvement on Y-BOCS or no better than score of 3 (minimal improvement) on CGI to SSRI. No minimum Y-BOCS specified

Placebo (21)

(168.75, 120.82)

Fineberg, 2005 [21]

Quetiapine (11)

25 - 400

16

12 (routine care SSRI)

Not known

Not known

< 25% improvement on Y-BOCS to SSRI and Y-BOCS ≥ 18

Placebo (10)

(215, 124)

Kordon, 2008 [22]

Quetiapine (20)

400 - 600

12

12 (routine care SSRI)

17.5% had two or more trials 82.5% had at least one trial

100% at least one trial

< 25% improvement on Y-BOCS to SSRI and Y-BOCS ≥18

Placebo (20)

Diniz, 2011 [23]

Quetiapine (18)

50 - 200

12

8 (open label fluoxetine)

Most had failed their first adequate SSRI trial

11% at least 1 trial

<35% improvement on Y-BOCS to SSRI and Y-BOCS ≥16

Placebo (18)

(142, 65)

Clomipramine (18)

Muscatello, 2011 [24]

Aripiprazole (20)

15

16

12 (routine care SSRI)

Not known

Not known

Y-BOCS ≥16

Placebo (20)

(fixed dose)

Sayyah, 2012 [25]

Aripiprazole (21)

10

12

12 (routine care SSRI)

Not known

Not known

Y-BOCS ≥21

Placebo (18)

(fixed dose)