Table 3

Responses to immunotherapy among 142 patients with GAD65 neurological autoimmunity

Stiff-person spectrum disorders (SPSD)
(n=44)
Cerebellar ataxia
(n=38)
Epilepsy
(n=20)
Limbic encephalitis
(n=7)
Overlap syndromes
(n=33)*
P value
Type of immunotherapy administered†
 Corticosteroids (%)7/44 (16)30/38 (79)15/20 (75)6/7 (86)20/33 (61)<0.0001
 Intravenous IG (%)38/44 (86)20/38 (53)13/20 (65)6/7 (86)26/33 (79)0.09
 PLEX (%)7/44 (16)9/38 (24)3/20 (15)1/7 (14)8/33 (24)0.33
 Rituximab (%)5/44 (11)4/38 (11)3/20 (15)3/7 (43)3/33 (9)0.07
 Cyclophosphamide (%)1/44 (2)3/38 (8)0/20 (0)1/7 (14)2/33 (6)0.25
Median time from symptom onset to first immunotherapy in months (range)30 (1–540)13 (1–96)50.5 (1–324)5 (1–22)12 (1–84)<0.0001
Response to immunotherapy (%)§34/44 (77)22/38 (58)10/20 (50)5/7 (71)23/33 (70)0.19
Partial response (%)24/44 (55)17/38 (45)7/20 (35)4/7 (57)19/33 (58)
Near-complete response (%)10/44 (23)4/38 (11)2/20 (10)1/7 (14)4/33 (12)
Complete response (%)0/44 (0)1/38 (3)1/20 (5)0/7 (0)0/33 (0)
No of initial responders who had sustained response to immunotherapy (%)32/34 (94)16/22 (73)5/10 (50)3/5 (60)13/23 (57)
No of all treated patients who had sustained response to immunotherapy (%)32/44 (73)16/38 (42)5/20 (25)3/7 (43)13/33 (39)0.002
  • *Best response to immunotherapy is reported (eg, if patient had no response to corticosteroids but partial response to intravenous IG, partial response to immunotherapy was reported).

  • †In addition to the immunotherapies listed, two patients with SPSD underwent autologous stem cell transplantation.

  • ‡In patients with overlap syndromes, time from symptom onset to first immunotherapy refers to time from onset of symptom being targeted for treatment (eg, if patient was treated with corticosteroids for new-onset cerebellar ataxia but had remote-onset medically-controlled epilepsy, time from symptom onset to first immunotherapy refers to time from cerebellar ataxia onset, not epilepsy onset).

  • §Best response to immunotherapy is reported (eg, if patient had no response to corticosteroids but partial response to intravenous IG, partial response to immunotherapy was reported).

  • GAD65, glutamic acid decarboxylase-65; PLEX, plasma exchange.