Spectrum Pharmaceuticals Highlights Data Showing Poziotinib Overcomes De Novo Resistance of HER2 Exon 20 Insertion Mutations in NSCLC and Other Cancers at the American Association for Cancer Research (AACR) in Chicago

HENDERSON, Nev.–(BUSINESS WIRE)–Spectrum Pharmaceuticals (NasdaqGS: SPPI), a biotechnology Company with
fully integrated commercial and drug development operations with a
primary focus in Hematology and Oncology, announced a poster
presentation of data from preclinical and clinical studies evaluating
poziotinib in HER2 exon 20 mutations in non-small cell lung cancer
(NSCLC) and summarizing a dataset of the prevalence of HER2 exon 20
across solid tumors by scientists from the University of Texas MD
Anderson Cancer Center at the American Association for Cancer Research
(AACR) which is taking place in Chicago, Illinois, April 14-18, 2018.

“We are excited to see the first presentation of data for poziotinib in
HER2 exon 20 mutations in NSCLC,” said Joe Turgeon, President and Chief
Executive Officer of Spectrum Pharmaceuticals. “These data build upon
previous results from poziotinib studies and indicate that this drug
could be effective in treating both EGFR and HER2 exon 20 mutations.
Furthermore, new data from MD Anderson reveal that these mutations are
found across a variety of solid tumors and there is strong rationale for
evaluating poziotinib in a basket study.”

“The pre-clinical and early clinical activity of poziotinib in EGFR and
HER2 exon 20 mutant NSCLC suggests poziotinib could be a promising agent
for the numerous cancer types driven by HER2 exon 20 mutations,” said
Jacqulyne Robichaux, Ph.D, Thoracic/Head and Neck Medical
Oncology, The University of Texas MD Anderson Cancer Center. “We have
previously shown that poziotinib is an effective inhibitor of EGFR exon
20 insertion mutations in vitro and in vivo. These data show that
poziotinib overcomes de novo resistance of HER2 exon 20 mutations in
NSCLC and other cancers. Further evaluation of poziotinib in solid
tumors is warranted.”

About Poziotinib

Poziotinib is a novel, Epidermal Growth Factor Receptor Tyrosine Kinase
Inhibitor (EGFR TKI) that inhibits the tyrosine kinase activity of EGFR
as well as HER2 and HER4. Importantly this, in turn, leads to the
inhibition of the proliferation of tumor cells that overexpress these
receptors. Mutations or overexpression/amplification of EGFR family
receptors have been associated with a number of different cancers,
including non-small cell lung cancer (NSCLC), breast cancer, and gastric
cancer. Spectrum received exclusive license to develop, manufacture, and
commercialize worldwide excluding Korea and China from Hanmi
Pharmaceuticals. Poziotinib is currently being investigated by Spectrum
and Hanmi in several mid-stage trials in multiple solid tumor
indications.

About Spectrum Pharmaceuticals, Inc.

Spectrum Pharmaceuticals is a leading biotechnology Company focused on
acquiring, developing, and commercializing drug products, with a primary
focus in Hematology and Oncology. Spectrum currently markets six
hematology/oncology drugs, and has an advanced stage pipeline that has
the potential to transform the Company. Spectrum’s strong track record
for in-licensing and acquiring differentiated drugs, and expertise in
clinical development have generated a robust, diversified, and growing
pipeline of product candidates in advanced-stage Phase 2 and Phase 3
studies. More information on Spectrum is available at www.sppirx.com.

Forward-looking statement – This press release may contain
forward-looking statements regarding future events and the future
performance of Spectrum Pharmaceuticals that involve risks and
uncertainties that could cause actual results to differ materially.
These
statements are based on management’s current beliefs and expectations.

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prove safe or effective, the possibility that our existing and new
applications to the FDA and other regulatory agencies may not receive
approval in a timely manner or at all, the possibility that our existing
and new drug candidates, if approved, may not be more effective, safer
or more cost efficient than competing drugs, the possibility that our
efforts to acquire or in-license and develop additional drug candidates
may fail, our dependence on third parties for clinical trials,
manufacturing, distribution and quality control and other risks that are
described in further detail in the Company’s reports filed with the
Securities and Exchange Commission.
The Company does not plan to
update any such forward-looking statements and expressly disclaims any
duty to update the information contained in this press release except as
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registered trademark of Spectrum Pharmaceuticals, Inc and its affiliate.

REDEFINING CANCER CARE™ and the Spectrum Pharmaceuticals logos are
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© 2018 Spectrum Pharmaceuticals, Inc. All Rights Reserved

Contacts

Spectrum Pharmaceuticals
Shiv Kapoor
Vice President, Strategic
Planning & Investor Relations
702-835-6300
InvestorRelations@sppirx.com