A phase II study of talimogene laherparepvec for patients with inoperable locoregional recurrence of breast cancer
Megumi Kai, Angela Marx, Diane D. Liu, Yu Shen, Hui Gao, James M. Reuben, Gary J. Whitman, Savitri Krishnamurthy, Merrick I. Ross, Jennifer K. Litton, Bora Lim, Nuhad K. Ibrahim, Takahiro Kogawa, Naoto T. Ueno
Abstract
Abstract Talimogene laherparepvec (T-VEC) is an immunotherapy that generates local tumor lysis and systemic antitumor immune response. We studied the efficacy of intratumoral administration of T-VEC as monotherapy for inoperable locoregional recurrence of breast cancer. T-VEC was injected intratumorally at 10 6 PFU/mL on day 1 (cycle 1), 10 8 PFU/mL on day 22 (cycle 2), and 10 8 PFU/mL every 2 weeks thereafter (cycles ≥ 3). Nine patients were enrolled, 6 with only locoregional disease and 3 with both locoregional and distant disease. No patient completed the planned 10 cycles or achieved complete or partial response. The median number of cycles administered was 4 (range, 3–8). Seven patients withdrew prematurely because of uncontrolled disease progression, 1 withdrew after cycle 3 because of fatigue, and 1 withdrew after cycle 4 for reasons unrelated to study treatment. Median progression-free survival and overall survival were 77 days (95% CI, 63–NA) and 361 days (95% CI, 240–NA). Two patients received 8 cycles with clinically stable disease as the best response. The most common grade 2 or higher adverse event was injection site reaction (n = 7, 78%). Future studies could examine whether combining intratumoral T-VEC with concurrent systemic therapy produces better outcomes.