Puma Biotechnology Expands Cohorts in Phase II SUMMIT Trial of Neratinib in Cancer Patients with Tumors with Activating EGFR or HER2 Mutations

April 4, 2019 Off By BusinessWire

LOS ANGELES–(BUSINESS WIRE)–Puma Biotechnology, Inc. (NASDAQ: PBYI), a biopharmaceutical company,
has expanded two additional cohorts from the Phase II SUMMIT clinical
trial investigating its lead drug candidate neratinib in patients with
solid tumors who have an activating EGFR or HER2 mutation. The cohorts
that have been expanded are (i) HER2 mutant patients with metastatic
salivary gland cancer and (ii) patients with EGFR exon 18
mutation-positive lung cancer.

The Phase II SUMMIT basket trial is an open-label, multi-center,
multi-histology, international study to evaluate the safety and efficacy
of neratinib administered daily to patients who have solid tumors with
activating EGFR, HER2 or HER4 mutations. The salivary gland cancer
patients initially entered the study in the “other solid tumors with a
HER2 mutation” cohort, and due to the preliminary activity seen in the
trial, the Company has expanded a separate salivary gland cancer cohort
pursuant to the protocol for the trial. The expanded HER2-mutant
salivary gland cancer cohort and the expanded EGFR exon 18 mutant lung
cancer cohort will each now enroll approximately 18 patients.

“We are pleased to expand our evaluation of neratinib in metastatic HER2
mutant salivary gland cancer and exon 18 mutated lung cancer from
SUMMIT, as they both represent orphan and deadly diseases with few
treatment options,” said Alan H. Auerbach, Chief Executive Officer and
President of Puma. “We believe this once again demonstrates the value of
the basket study approach, in particular for developing targeted therapy
for rare diseases with clinically-actionable mutations. We look forward
to continuing enrollment into these expanded cohorts and presenting
updated trial results.”

About Puma Biotechnology:

Puma Biotechnology, Inc. is a biopharmaceutical company with a focus on
the development and commercialization of innovative products to enhance
cancer care. The Company in-licenses the global development and
commercialization rights to three drug candidates — PB272 (neratinib,
oral), PB272 (neratinib, intravenous) and PB357. Neratinib, oral was
approved by the U.S. Food and Drug Administration in July 2017 for the
extended adjuvant treatment of adult patients with early stage
HER2-overexpressed/amplified breast cancer, following adjuvant
trastuzumab-based therapy, and is marketed in the United States as
NERLYNX® (neratinib) tablets. NERLYNX was granted marketing
authorization by the European Commission in September 2018 for the
extended adjuvant treatment of adult patients with early stage hormone
receptor-positive HER2-overexpressed/amplified breast cancer and who are
less than one year from completion of prior adjuvant trastuzumab-based
therapy. NERLYNX is a registered trademark of Puma Biotechnology, Inc.

Further information about Puma Biotechnology may be found at www.pumabiotechnology.com.

Forward-Looking Statements:

This press release contains forward-looking statements, including
statements regarding the expected timing for presentation of clinical
trial results. All forward-looking statements involve risks and
uncertainties that could cause Puma’s actual results to differ
materially from the anticipated results and expectations expressed in
these forward-looking statements. These statements are based on current
expectations, forecasts and assumptions, and actual outcomes and results
could differ materially from these statements due to a number of
factors, which include, but are not limited to, the risk factors
disclosed in the periodic and current reports filed by Puma with the
Securities and Exchange Commission from time to time, including Puma’s
Annual Report on Form 10-K for the year ended December 31, 2018. Readers
are cautioned not to place undue reliance on these forward-looking
statements, which speak only as of the date hereof. Puma assumes no
obligation to update these forward-looking statements, except as
required by law.