Verastem Announces Oral Presentation of Data Supporting the Preferential Targeting of Ovarian Cancer Stem Cells at the Society of Gynecologic Oncology’s 2016 Annual Meeting on Women’s Cancer

BOSTON–(BUSINESS WIRE)–Verastem, Inc. (NASDAQ:VSTM), focused on discovering and developing
drugs to treat cancer, today announced the presentation of scientific
data at the Society of Gynecologic Oncology’s 2016 Annual Meeting on
Women’s Cancer being held March 19-22, 2016 in San Diego, CA.

“The data presented today at SGO 2016 are important because they provide
further scientific evidence that chemotherapy can lead to an increase in
ovarian cancer stem cells (CSCs), making the tumor more aggressive and
resistant to further treatment,” said Dr. Jonathan Pachter, Verastem
Head of Research. “At Verastem, we believe that our compounds in
development may be especially beneficial as therapeutics when used in
combination with other agents, including current and emerging standard
of care treatments and immunotherapies, and have the potential to create
a more durable clinical response. We look forward to the initiation of a
Phase 1/1b clinical trial of the combination of VS-6063 and avelumab, in
collaboration with Pfizer and Merck KGaA, for patients with ovarian
cancer in the second half of this year.”

Verastem, and its collaborators, are presenting these scientific data in
support of Verastem’s development programs which utilize a multi-faceted
approach to treat cancer by reducing cancer stem cells, enhancing
anti-tumor immunity, and modulating the local tumor microenvironment.
The Company’s most advanced clinical product candidates are the Focal
Adhesion Kinase inhibitors, VS-6063 and VS-4718, and the dual PI3K/mTOR
inhibitor, VS-5584. Research on the FAK and PI3K/mTOR signaling pathways
has revealed critical roles for each in cancer stem cell survival and
disease progression.

Details for the SGO presentation are as follows:

Oral Presentation

Title: Standard chemotherapy for ovarian cancer increases
expression of cancer stem cell biomarkers which is predictive of survival

Session: Scientific Plenary IX: Ovary

Date and time: Tuesday, March 22, 2016 at 8:30 – 10:05 AM

Location: Hall A

Summary: In ovarian cancer, certain molecular mediators are
thought to possess CSC characteristics and the presence of these
mediators, which is linked to earlier recurrence and shorter survival,
is possibly brought about by chemotherapy. The aim of this study was to
explore the effect of chemotherapy on ovarian cancer stem-like mediators
and to determine if there was a relationship to survival. Researchers
obtained matched pre- and post-chemotherapy tumor specimens from stage
IIIC/IV ovarian cancer patients (n=22) who all underwent neoadjuvant
chemotherapy with interval debulking surgery. Samples were then analyzed
for expression of 27 CSC markers. CSC markers were then validated in
tumorsphere model and in vivo tumor initiating studies.

All 27 CSC markers demonstrated a mean increase in gene expression after
exposure to chemotherapy. A 3-fold or greater increase in gene
expression after exposure to chemotherapy was seen in 8 of 27 (30%)
markers: ABCG2, ALDH1A1, CTGF, DPP4, MYC, CD133, SOX2, and POSTN. Three
markers demonstrated a significant fold increase that correlated with
platinum resistance: POSTN (4.1-fold), ALDH1A1 (5-fold), and SOX2
(14.5-fold). When implanted into immunocompromised mice, SOX2(hi) cells
exhibited significantly higher levels of tumorsphere forming potential
than SOX2(lo) cells and were more tumorigenic. High gene expression in
these 3 markers demonstrated shorter progression free survival, compared
to low expression. These results support the further investigation of
directed agents to inhibit these CSC markers to potentially extend
survival for patients with ovarian cancer.

A copy of the oral presentation will be available at http://bit.ly/R3M6wc

About Verastem, Inc.

Verastem, Inc. (NASDAQ:VSTM) is a biopharmaceutical company focused on
discovering and developing drugs to improve outcomes for patients with
cancer. Our product candidates utilize a multi-faceted approach to treat
cancer by reducing cancer stem cells, enhancing anti-tumor immunity, and
modulating the local tumor microenvironment. Our most advanced clinical
product candidates are the Focal Adhesion Kinase inhibitors, VS-6063 and
VS-4718, and the dual PI3K/mTOR inhibitor, VS-5584. For more
information, please visit www.verastem.com.

Verastem forward-looking statements notice:

This press release includes forward-looking statements about Verastem’s
strategy, future plans and prospects, including statements regarding the
development and activity of Verastem’s product candidates, VS-6063,
VS-4718 and VS-5584, and Verastem’s FAK, PI3K/mTOR and diagnostics
programs generally, the utility of FAK inhibitors for the treatment of
cancer, the timeline for clinical development and regulatory approval of
our product candidates, the structure of our planned or pending clinical
trials, our rights to develop or commercialize our product candidates
and our ability to finance contemplated development activities and fund
operations for a specified period. The words “anticipate,” “appear,”
“believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,”
“project,” “target,” “potential,” “will,” “would,” “could,” “should,”
“continue,” and similar expressions are intended to identify
forward-looking statements, although not all forward-looking statements
contain these identifying words. Each forward-looking statement is
subject to risks and uncertainties that could cause actual results to
differ materially from those expressed or implied in such statement.
Applicable risks and uncertainties include the risks that the
preclinical testing of Verastem’s product candidates and preliminary or
interim data from clinical trials may not be predictive of the results
or success of ongoing or later clinical trials, that data may not be
available when we expect it to be, that enrollment of clinical trials
may take longer than expected, that our product candidates will cause
unexpected safety events, that Verastem will be unable to successfully
initiate or complete the clinical development of its product candidates,
that the development of Verastem’s product candidates will take longer
or cost more than planned, and that Verastem’s product candidates will
not receive regulatory approval or become commercially successful
products. Other risks and uncertainties include those identified under
the heading “Risk Factors” in Verastem’s Annual Report on Form 10-K for
the year ended December 31, 2015 and in any subsequent SEC filings. The
forward-looking statements contained in this press release reflect
Verastem’s current views with respect to future events, and Verastem
does not undertake and specifically disclaims any obligation to update
any forward-looking statements.

Contacts

Verastem, Inc.
Brian Sullivan, 781-292-4214
bsullivan@verastem.com