Immunomedics Announces Encouraging Early-Stage Clinical Results with Trodelvy in Brain Cancers

Results include partial responses in small cohort of patients with brain metastasis from breast cancer (BMBC) and recurrent glioblastoma (rGBM)

MORRIS PLAINS, N.J., Sept. 18, 2020 (GLOBE NEWSWIRE) -- Immunomedics, Inc. (NASDAQ: IMMU) (“Immunomedics” or the “Company”), a leading biopharmaceutical company in the area of antibody-drug conjugates, today announced that Trodelvy delivered 150-fold and 40-fold the 50% inhibitory concentration (IC50) of SN-38 for BMBC and rGBM, respectively, and produced partial responses in both cohorts of brain cancer patients.

“These early intracranial responses are very encouraging signs of sacituzumab govitecan’s activity in central nervous system (CNS) tumors as previously observed in preclinical models,”¹ said Andrew J. Brenner, M.D. Ph.D., Clinical Investigator, Institute for Drug Development; Co-Leader, Experimental and Developmental Therapeutics Program; S & B Kolitz/CTRC-Zachry Endowed Chair in Neuro-Oncology Research, Mays Cancer Center at UT Health San Antonio, San Antonio, TX, who reported the results in a mini oral session on CNS tumors at the ESMO Virtual Congress 2020. “With a hydrolysable linker that allows SN-38 to be released at the tumor site and given that SN-38 freely crosses the blood brain barrier and is active in the nanomolar range for most cancer cells, including triple-negative breast cancer (TNBC) and GBM, sacituzumab govitecan has the prerequisite ability to deliver therapeutically relevant concentrations of SN-38 across an undisrupted vasculature. The early clinical results in patients with neoplastic involvement of the brain warrant further development of Trodelvy in these aggressive and lethal cancers.”

At the time of data cutoff, 19 patients (7 BMBC and 12 rGBM) were enrolled into the study. Key clinical data from evaluable patients are summarized below. No new safety signals were observed.

	BMBC	rGBM
Tumor response*, N	7	7
Partial response, n	2	2
Ongoing progression-free survival, n (range)	4 (161-279 days)	6 (7-315 days)
Residual measurable disease, n	4	7
Tumor SN-38 concentrations, N	4	6
Mean total SN-38 (nM) (range)	455 (174-1,160)	270 (93-687)
Mean free SN-38 (nM) (range)	73 (15-198)	46 (20-90)
SN-38G# detected in 1 patient in each cohort (nM)	3.4	5.8
* Per RANO criteria, # SN-38 glucuronide, an inactive metabolite of SN-38