Treatment of relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma with the BTK inhibitor zanubrutinib: phase 2, single-arm, multicenter study

Table 2 Independent review committee-assessed efficacy outcomes

Efficacy variable	N = 91
Objective response,n(%)
CR	3 (3.3)
CRi	0 (0.0)
nPR	0 (0.0)
PR	54 (59.3)
PR-L	20 (22.0)
No response^a	8 (8.8)
Not evaluable^b	6 (6.6)
Overall (%)	84.6
95% CI for overall response rate	75.5, 91.3
P value^c	< 0.0001
Time to response,^dmonths
Median (range)	2.8 (2.6–8.4)
Duration of response, months
Median^e (range)	NE
95% CI	NE, NE
Event-free rates^f at 12 months (%)	92.9
95% CI	83.6, 97.0
Progression-free survival, months
Median^e (range)	NE
95% CI	NE, NE
Event-free rates^f at 12 months (%)	87.2
95% CI	78.0, 92.7

Efficacy outcomes were assessed in accordance with International Workshop on Chronic Lymphocytic Leukemia guidelines [20] for CLL patients and the Lugano classification [22] for SLL patients
CR complete response, CRi complete response with incomplete bone marrow recovery, NE not estimable, nPR nodular partial response, ORR overall response rate, PR partial response, PR-L partial response with lymphocytosis
^aIncludes all patients with a best overall response of stable disease or progressive disease
^bTwo patients had incomplete imaging studies; one patient had only one response assessment without evidence of response maintenance for at least 2 months; three patients discontinued prior to first post-baseline assessment
^cOne-sided P value was based on exact test comparison of zanubrutinib ORR versus reference rate (H₀) of 0.32
^dSummarized for patients who achieved a response of PR-L or better
^eMedians were estimated by Kaplan-Meier methodology with 95% confidence intervals estimated using the Brookmeyer and Crowley method [27]. NE denotes not estimable
^fEvent-free rates were estimated by Kaplan-Meier methodology with 95% confidence intervals estimated using Greenwood’s formula [28]

ISSN: 1756-8722