Clinical effects of prior trastuzumab on combination eribulin mesylate plus trastuzumab as first-line treatment for human epidermal growth factor receptor 2 positive locally recurrent or metastatic breast cancer: results from a Phase II, single-arm, multicenter study

Figures & data

Table 1 Demographic and clinical characteristics of study patients

	Eribulin/trastuzumab with prior trastuzumab n=21	Eribulin/trastuzumab without prior trastuzumab n=31	Overall N=52
Age (years)
Mean (SD)	61.5 (10.6)	56.8 (10.9)	58.7 (10.9)
Median	65.0	56.0	59.5
Minimum—maximum	42.0–78.0	31.0–81.0	31.0–81.0
Age group, n (%)
<50 years	3 (14.3)	8 (25.8)	11 (21.2)
50–65 years	7 (33.3)	17 (54.8)	24 (46.2)
≥65 years	11 (52.4)	6 (19.4)	17 (32.7)
Age at diagnosis, median (years) Sex, n (%)	59.5	56.6	57.7
Female	21 (100)	30 (96.8)	51 (98.1)
Male	0	1 (3.2)	1 (1.9)
Estrogen receptor status, n (%)
+	12 (57.1)	23 (74.2)	35 (67.3)
−	9 (42.9)	7 (22.6)	16 (30.8)
Not done	0	1 (3.2)	1 (1.9)
Progesterone receptor status, n (%)
+	7 (33.3)	15 (48.4)	22 (42.3)
−	14 (66.7)	15 (48.4)	29 (55.8)
Not done	0	1 (3.2)	1 (1.9)
Time since prior trastuzumab use, months
Mean (SD)	29 (26)	NA	NA
Median	23	NA	NA
Minimum—maximum	0.7–114.1	NA	NA

Abbreviations: NA, not assessed; SD, standard deviation; min, minimum; max, maximum.

Table 2 Tumor responses

Response category	Eribulin/trastuzumab with prior trastuzumab n=21	Eribulin/trastuzumab without prior trastuzumab n=31
ORR (CR + PR), n (%)	13 (61.9)	24 (77.4)
95% CI	(38.4–81.9)	(58.9–90.4)
DOR, months (median)	9.5	11.8
95% CI	(3.6–NE)	(8.0–17.8)
CR, n (%)	2 (9.5)	1 (3.2)
PR, n (%)	11 (52.4)	23 (74.2)
SD, n (%)	6 (28.6)	7 (22.6)
PD, n (%)	1 (4.8)	0
Not evaluable, n (%)	1 (4.8)	0
CBR (CR + PR + SD ≥6 months), n (%)	17 (81.0)	27 (87.1)
95% CI	(58.1–94.6)	(70.2–96.4)
PFS, months (median)	11.5	12.2
95% CI	(6.0–13.9)	(7.3–19.1)

Abbreviations: CBR, clinical benefit rate; CI, confidence interval; CR, complete response; DOR, duration of response; NE, nonestimable; ORR, objective response rate; PD, progressive disease; PFS, progression-free survival; PR, partial response; SD, stable disease.

Figure 1 Waterfall graphs of percentage change in total sum of target lesion longest diameter.

Note: Diameters from baseline to postbaseline nadir (RECIST version 1.1).
Abbreviations: RECIST, Response Evaluation Criteria in Solid Tumors version 1.1; T, trastuzumab.

Figure 2 Kaplan–Meier plot of progression-free survival.

Abbreviation: T, trastuzumab.

Table 3 Treatment-emergent adverse events

TEAE	All grades, n (%)a		Grade 3/4/5, n (%)b
	With prior trastuzumab n=21	Without prior trastuzumab n=31	With prior trastuzumab n=21	Without prior trastuzumab n=31
Alopecia	18 (85.7)	28 (90.3)	1 (4.8)	1 (3.2)
Fatigue	15 (71.4)	21 (67.7)	2 (9.5)	2 (6.5)
Neutropenia	13 (61.9)	18 (58.1)	10 (47.6)	10 (32.3)
Peripheral neuropathy	12 (57.1)	19 (61.3)	3 (14.3)	8 (25.8)
Nausea	11 (52.4)	13 (41.9)	2 (9.5)	0
Decreased appetite	8 (38.1)	5 (16.1)	0	0
Constipation	7 (33.3)	6 (19.4)	0	0
Headache	7 (33.3)	3 (9.7)	1 (4.8)	1 (3.2)
Anemia	6 (28.6)	7 (22.6)	0	1 (3.2)
Bone pain	6 (28.6)	1 (3.2)	0	0
Diarrhea	6 (28.6)	11 (35.5)	1 (4.8)	1 (3.2)
Pyrexia	6 (28.6)	6 (19.4)	1 (4.8)	0
Vomiting	5 (23.8)	7 (22.6)	2 (9.5)	1 (3.2)
Dysgeusia	3 (14.3)	9 (29.0)	0	0
Febrile neutropenia	3 (14.3)	1 (3.2)	3 (14.3)	1 (3.2)
Leukopenia	3 (14.3)	6 (19.4)	2 (9.5)	1 (3.2)
Peripheral sensory neuropathy	3 (14.3)	6 (19.4)	0	3 (9.7)

Notes:

a In >25% of patients.

b In >5% of patients.

Abbreviation: TEAE, treatment-emergent adverse event.