Table 2.

Adverse Events through 18 Months.^*

Variable	Rituximab (N = 99)	Cyclophosphamide– Azathioprine (N = 98)	Total (N = 197)	P Value
Total no. of participant-months	1371.5	1331.9	2703.4
Adverse events
Total no. of events	1399	1420	2819
Participants with ≥1 event — no. (%)	98 (99)	98 (100)	196 (99)	>0.99
Events/participant-mo	1.02	1.07	1.04	0.24
Serious adverse events
Total no. of events	59	63	122
Participants with ≥1 event — no. (%)	42 (42)	37 (38)	79 (40)	0.50
Events/participant-mo	0.04	0.05	0.05	0.63
Deaths — no. (%)†	2 (2)	2 (2)	4 (2)
Participants with ≥1 episode of leukopenia of grade 2 or higher — no. (%)	5 (5)	23 (23)	28 (14)	<0.001
Participants with ≥1 episode of infection of grade 3 or higher — no. (%)	12 (12)	11 (11)	23 (12)	>0.99
Pneumonia-related adverse events
Total no. of events	4	11	15
Participants with ≥1 episode of pneumonia — no. (%)	3 (3)	11 (11)	14 (7)	0.03
Pneumonia-related adverse events/participant-mo	0.0029	0.0083	0.0055	0.08

^*Data were censored at time of crossover, initiation of open-label treatment for severe relapse, or a change in treatment according to best medical judgment.

^†Deaths that occurred after the date on which data were censored are included when the death was attributable to an adverse event that started before that date (see the Supplementary Appendix for details about deaths).