Navidea Biopharmaceuticals, Inc. (NYSE Amex: NAVB), a specialty
pharmaceutical company focused on precision diagnostic
radiopharmaceuticals, today announced that data from its Phase 3
clinical study investigating 99m-Tc-Tilmanocept (Lymphoseek®) in oral
and squamous cell cancers (SCC) were presented as a poster presentation
at the 65th Annual Cancer Symposium of the Society of Surgical
Oncology (SSO) meeting held in Orlando, Florida, March 21-24, 2012.
The data presented by investigator Stephen Y. Lai, M.D., Ph.D., FACS, of
the University of Texas MD Anderson Cancer Center, describe the Center's
initial experience with Lymphoseek in Sentinel Lymph Node (SLN) mapping
in nine patients with head and neck SCC (HNSCC).
Frederick O. Cope, Ph.D., FACN, Navidea's Senior Vice President of
Pharmaceutical Research and Clinical Development commented, "These data
comprise the first presentation of Lymphoseek's potential utility in
oral cancers. The presentation by Dr. Lai suggests that Lymphoseek's
previously reported ability to accurately facilitate identification of
primary draining nodes necessary to properly stage patients with breast
cancer or melanoma may also apply in patients with HNSCC. We believe
this is due to Lymphoseek's rapid transit through lymphatic vessels and
targeted binding to the mannose binding receptors (MBR) within key
predictive nodes. The results in these nine patients demonstrated a
false negative rate of zero, the same as obtained with full nodal
dissection. However, using Lymphoseek, substantially fewer lymph nodes
are removed than with full nodal dissection. This may enable surgeons to
reduce the need for more extensive lymph node dissection, potentially
sparing them from the morbidity and side effects of full nodal
dissection while not sacrificing accuracy in the detection of key
predictive lymph nodes identified by more aggressive full regional
dissection."
The ongoing trial (NEO3-06; NCT00911326) is a multicenter, open-label,
non-randomized, single arm, within-group trial of Lymphoseek for the
detection of tumor-draining Sentinel Lymph Nodes in subjects with known
cutaneous or mucosal SCC of the head and neck. All subjects received a
single dose of Lymphoseek. The presented data represent the findings
from nine subjects who were injected, underwent surgery, and completed a
30-day follow up at MD Anderson. Most subjects were injected on the day
prior to their surgical procedure. In the NEO3-06 trial, all subjects
received the standard treatment of a full regional nodal dissection and
the results of Lymphoseek-identified nodes were compared to
pathology-positive nodes obtained from the full regional nodal
dissection. In the nine subjects reported on by Dr. Lai, a total of 360
nodes were excised (22-55 non-SLNs identified per patient, median 39,
average 40). The data show preoperative imaging with Lymphoseek provided
accurate correlation of lymphatic drainage to tumor-involved anatomic
regions and nodes, including SLNs contralateral to (opposite) the
primary tumor. The 0% false negative rate (FNR) in this small initial
cohort indicates that Lymphoseek accurately identifies those nodes with
the highest probability of accurately reflecting the status of
regional/cervical metastases (i.e., SLNs). There have been no
significant adverse events related to the use of Lymphoseek.
"Patients with HNSCC may have more than one sentinel (or primary
drainage) lymph node, and all of these lymph nodes need to be excised
and evaluated in order to accurately stage and manage our patients,"
said Dr. Lai. "Our initial clinical experience with Lymphoseek
demonstrates the utility, diagnostic predictive value, and safety of
99m-Tc-Tilmanocept for both preoperative lymphoscintigraphy and
intraoperative localization. The 100% agreement of Sentinel Lymph Node
status with the pathology findings in the complete neck dissection
supports the efficacy of both Lymphoseek and the Sentinel Lymph Node
approach for the care of our patients."
The results presented by Dr. Lai are interim results from his clinical
site's participation in NEO3-06 that may or may not be consistent with
the complete data that will be available when the trial is completed,
and the percentage agreement between the nodes identified by Lymphoseek
and the pathology results from a complete neck dissection may decline
upon analysis of the data from the completed trial.