Navidea Biopharmaceuticals Announces Results from Lymphoseek® Study on Accuracy of Lymph Node Detection from Injection Time to

  Navidea Biopharmaceuticals Announces Results from Lymphoseek® Study on
  Accuracy of Lymph Node Detection from Injection Time to Surgery

   - Lymphoseek demonstrated reliable identification of lymph nodes over 15
  minutes to 30 hours, typical timeframes for lymphatic mapping in clinical
                                  setting -

Business Wire

DUBLIN, Ohio -- June 11, 2013

Navidea Biopharmaceuticals, Inc. (NYSE MKT: NAVB), a biopharmaceutical company
focused on precision diagnostic radiopharmaceuticals, today announced positive
results from a meta-analysis study of Lymphoseek^® (technetium Tc 99m
tilmanocept) Injection that compared the performance of Lymphoseek, a novel,
receptor-targeted radiopharmaceutical recently approved by the U.S. Food and
Drug Administration, against a commonly used agent, vital blue dye (VBD), in
identifying lymph nodes likely to harbor cancer cells over a period of time
after injection.

Study results indicated that Lymphoseek demonstrated reliable
histopathological detection of lymph nodes in lymphatic mapping across the
likely time range of the procedure from injection to surgery: 15 minutes to 30
hours. The data were presented in an oral presentation by James O’Donnell, MD,
of Case Western University Hospitals, Cleveland, Ohio, at the 2013 Annual
Meeting of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) in
Vancouver, Canada.

“As a synthetic, small-sized molecule, Lymphoseek clears the injection site
quickly and reliably,” said Frederick O. Cope, PhD, Senior Vice President,
Pharmaceutical Research and CSO at Navidea Biopharmaceuticals. “The unique
receptor-targeting characteristics of Lymphoseek allow for effective and
durable identification of tumor-draining lymph nodes, as was clearly
demonstrated by this study. This intentionally designed mechanism of action
allows Lymphoseek to tightly bind to those lymph nodes that drain from a
tumor, where they are retained and can be detected, rather than passively
flowing through them as is the case with other agents. As evidenced in this
study, Lymphoseek demonstrated the ability to be utilized across time ranges
that may be encountered in the clinical setting, from as early as 15 minutes
up to 30 hours.”

“The ability to reliably schedule lymphatic mapping procedures is important
for physicians to efficiently utilize medical resources and staff, and is
important for the breast cancer and melanoma patients who want their
procedures performed quickly and efficiently during this anxious time,” said
Dr. O’Donnell, Division Chief, Nuclear Medicine, at UH Case Medical Center.
“Dynamics that confront physicians in the clinic revolve around how rapidly a
tracing agent clears the injection site, how long it remains in the lymph
nodes to enable a lymphatic mapping procedure to be conducted, and most
importantly, how accurate the agent may be in identifying the lymph nodes most
likely to harbor tumor metastases. This study was designed to compare the
performance of Lymphoseek and VBD with those specific considerations in mind.”

In the study, 332 patients were evaluated in two Phase 3 clinical trials that
compared Lymphoseek and VBD in patients with breast cancer and melanoma. A
meta-analysis of the rate of agreement (concordance) of Lymphoseek to VBD
localization was conducted. The time from injection to surgery was used as a
measure to compare efficacy for five discrete time periods (0 to<15 minutes,
15 minutes to < 2 hours, 2 hours to-<6 hours, 6 hours to <10 hours and 15
hours to 30 hours), as were pathology findings for combined time window
segments relative to VBD. Combined meta-analysis nodal concordance was 99.9%.
The overall reverse concordance (radioactive nodes that were also dyed blue)
was 65.2%. The failed detection rate for pathology positive patients was 3.7%
for Lymphoseek and 22.2% for VBD.

About Lymphoseek^®

Lymphoseek^® (technetium Tc 99m tilmanocept) Injection is a novel,
receptor-targeted, small-molecule radiopharmaceutical used in lymphatic
mapping procedures that are performed to help in the diagnostic evaluation of
potential cancer spread for patients with breast cancer and melanoma.
Lymphoseek is designed to identify the lymph nodes that drain from a primary
tumor, which have the highest probability of harboring cancer. Lymphoseek was
approved by the U.S. Food and Drug Administration in March, 2013 for use in
lymphatic mapping to assist in the localization of lymph nodes draining a
primary tumor in patients with breast cancer or melanoma. The Company
anticipates continuing development of Lymphoseek into other solid tumor areas
that may include head and neck cancers, prostate cancer, thyroid cancer,
lung/bronchus cancers, colorectal cancer and others.

Accurate diagnostic evaluation of cancer is critical, as it guides therapy
decisions and determines patient prognosis and risk of recurrence. According
to the American Cancer Society, approximately 232,000 new cases of breast
cancer, 77,000 new cases of melanoma and 67,000 new cases of head and
neck/oral cancer are expected to be diagnosed in the United States in 2013.

U.S. Indication and Important Safety Information About Lymphoseek

Indication

Lymphoseek (technetium Tc 99m tilmanocept) Injection is a lymphatic mapping
agent indicated for use with a hand-held gamma counter to assist in the
localization of lymph nodes draining a primary tumor site in patients with
breast cancer or melanoma.

Important Safety Information

In clinical trials with Lymphoseek, no serious hypersensitivity reactions were
reported, however Lymphoseek may pose a risk of such reactions due to its
chemical similarity to dextran. Serious hypersensitivity reactions have been
associated with dextran and modified forms of dextran (such as iron dextran
drugs).

Prior to the administration of Lymphoseek, patients should be asked about
previous hypersensitivity reactions to drugs, in particular dextran and
modified forms of dextran. Resuscitation equipment and trained personnel
should be available at the time of Lymphoseek administration, and patients
observed for signs or symptoms of hypersensitivity following injection.

The most common adverse reactions are injection site irritation and/or pain
(<1%).

FULL LYMPHOSEEK PRESCRIBING INFORMATION CAN BE FOUND AT:

WWW.LYMPHOSEEK.COM

About Navidea Biopharmaceuticals, Inc.

Navidea Biopharmaceuticals, Inc. (NYSE MKT: NAVB) is a biopharmaceutical
company focused on the development and commercialization of precision
diagnostics and radiopharmaceutical agents. Navidea is actively developing
four radiopharmaceutical agent platforms – Lymphoseek^®, NAV4694, NAV5001 and
RIGScan^TM – to help identify the sites and pathways of undetected disease and
enable better diagnostic accuracy, clinical decision-making and, ultimately,
patient care. Navidea’s strategy is to deliver superior growth and shareholder
return by bringing to market novel radiopharmaceutical agents and advancing
the Company’s pipeline through selective acquisitions, global partnering and
commercialization efforts. For more information, please visit www.navidea.com.

The Private Securities Litigation Reform Act of 1995 (the Act) provides a safe
harbor for forward-looking statements made by or on behalf of the Company.
Statements in this news release, which relate to other than strictly
historical facts, such as statements about the Company’s plans and strategies,
expectations for future financial performance, new and existing products and
technologies, anticipated clinical and regulatory pathways, and markets for
the Company’s products are forward-looking statements within the meaning of
the Act. The words “believe,” “expect,” “anticipate,” “estimate,” “project,”
and similar expressions identify forward-looking statements that speak only as
of the date hereof. Investors are cautioned that such statements involve risks
and uncertainties that could cause actual results to differ materially from
historical or anticipated results due to many factors including, but not
limited to, the Company’s continuing operating losses, uncertainty of market
acceptance of its products, reliance on third party manufacturers, accumulated
deficit, future capital needs, uncertainty of capital funding, dependence on
limited product line and distribution channels, competition, limited marketing
and manufacturing experience, risks of development of new products, regulatory
risks and other risks detailed in the Company’s most recent Annual Report on
Form 10-K and other Securities and Exchange Commission filings. The Company
undertakes no obligation to publicly update or revise any forward-looking
statements.

Contact:

Navidea Biopharmaceuticals, Inc.
Brent Larson, 614-822-2330
Executive VP & CFO
or
Stern Investor Relations, Inc.
Beth DelGiacco, 212-362-1200