Ipsen Completes Acquisition of Clementia Pharmaceuticals

• Ipsen’s Rare Diseases portfolio significantly enhanced with
  late-stage drug candidate, palovarotene, for the treatment of rare
  bone disorders in adult and pediatric patients
• Transaction reinforces Ipsen’s strong commitment to providing
  life-altering treatments to patients with high unmet medical needs

PARIS–(BUSINESS WIRE)–Regulatory News:

Ipsen (Euronext: IPN; ADR: IPSEY) and Clementia Pharmaceuticals (NASDAQ:
CMTA) today announced the closing of Ipsen’s acquisition of Clementia
following approval of the arrangement by Clementia shareholders and the
Quebec Superior Court. Pursuant to the arrangement, Clementia
shareholders will receive US$25.00 per share in cash upfront and one
contingent value right (CVR) per share entitling them to receive US$6.00
per CVR upon the U.S. Food and Drug Administration’s (FDA) acceptance of
the regulatory filing for palovarotene for the treatment of multiple
osteochondromas (MO).

Clementia’s key late-stage clinical asset palovarotene is an
investigational retinoic acid receptor gamma (RARγ) selective agonist,
for the treatment of two rare bone disorders, fibrodysplasia ossificans
progressiva (FOP) and multiple osteochondromas (MO), and other diseases.

The palovarotene regulatory submission for the prevention of heterotopic
ossification (HO) in patients with FOP in the U.S. is expected for the
second half of 2019. The submission will be based on Phase 2 clinical
data from greater than 100 imaged flare-ups and indicated that treatment
with palovarotene resulted in a greater than 70% reduction of new
heterotopic ossification (HO), or bone formation, across all three
dosing levels.

Dr. Alexandre Lebeaut, Chief Scientific Officer of Ipsen,
commented, “We are encouraged by compelling and consistent clinical
data from the extensive Phase 2 program as well as fast-track,
breakthrough therapy, orphan drug and rare pediatric diseases
designations from the FDA. We are focused on the successful regulatory
submission of palovarotene as a first-in-class therapeutic solution for
patients with episodic flare-up treatment of fibrodysplasia ossificans
progressiva in the second half of 2019.”

Dr. Clarissa Desjardins, Chief Executive Officer of Clementia,
added, “I am extremely grateful for the hard-working and dedicated
team at Clementia, the patient community and the clinical trial
investigators who have helped advance the palovarotene program. Going
forward, we are confident that Ipsen, with its shared patient-centric
culture, proven development capabilities and global commercial
footprint, will fulfill our ambition of delivering palovarotene to
patients worldwide as quickly as possible.”

About
Fibrodysplasia Ossificans Progressiva (FOP)

FOP is an ultra-rare, severely disabling disorder characterized by
heterotopic ossification (HO), or bone that forms outside the normal
skeleton, in muscles, tendons or soft tissue. In FOP, HO progressively
restricts movement by locking joints, leading to a cumulative loss of
function, progressive disability, and increased risk of early death. FOP
is caused by a mutation in the ACVR1 gene, resulting in excess signaling
in the bone morphogenetic pathway, a key pathway controlling bone growth
and development, by way of both ligand-dependent and independent
mechanisms. The prevalence of FOP is approximately 1.3 individuals per
million lives, or approximately 9,000 patients globally. There are
currently no approved treatments for FOP.

About Multiple Osteochondromas (MO)

MO, also called multiple hereditary exostoses (MHE) is a rare, severely
disabling, progressive, chronic disease in which multiple benign bone
tumors, also known as osteochondromas (OCs) or osteocartilaginous
exostoses, develop on bones. MO is typically diagnosed in early
childhood when OCs become visible with a median age at diagnosis of four
years. Because of their development around joints, children develop limb
deformity and restricted movement as they grow. Today, the only
available treatments for MO are surgery and palliative care, and many
patients will undergo surgery, some as many as 30 surgeries, before
adulthood. MO is estimated to affect 20 individuals per million lives,
or approximately 150,000 globally. MO is among the most common inherited
bone disorders with multiple family members in multiple generations
affected.

About Palovarotene

Palovarotene is an RARγ agonist being developed as a treatment for
patients with ultra-rare/rare and debilitating bone diseases, including
fibrodysplasia ossificans progressiva (FOP) and multiple osteochondromas
(MO), as well as other diseases. Palovarotene was in-licensed from Roche
Pharmaceuticals, where it was previously evaluated in more than 800
subjects, including 450 patients treated for up to two years.
Palovarotene has received Orphan Drug status for FOP and MO from the
U.S. Food and Drug Administration (FDA) and the European Medicines
Agency (EMA). In addition, palovarotene has been granted Fast Track,
Breakthrough Therapy and Rare Pediatric Disease designations for FOP
from the FDA.

About Ipsen

Ipsen is a global specialty-driven biopharmaceutical group focused on
innovation and specialty care. The group develops and commercializes
innovative medicines in three key therapeutic areas – Oncology,
Neuroscience and Rare Diseases. Its commitment to Oncology is
exemplified through its growing portfolio of key therapies for prostate
cancer, neuroendocrine tumors, renal cell carcinoma and pancreatic
cancer. Ipsen also has a well-established Consumer Healthcare business.
With total sales over €2.2 billion in 2018, Ipsen sells more than 20
drugs in over 115 countries, with a direct commercial presence in more
than 30 countries. Ipsen’s R&D is focused on its innovative and
differentiated technological platforms located in the heart of the
leading biotechnological and life sciences hubs (Paris-Saclay, France;
Oxford, UK; Cambridge, US). The Group has about 5,700 employees
worldwide. Ipsen is listed in Paris (Euronext: IPN) and in the United
States through a Sponsored Level I American Depositary Receipt program
(ADR: IPSEY). For more information on Ipsen, visit www.ipsen.com.

About Clementia Pharmaceuticals Inc.

Clementia is a clinical-stage company innovating treatments for people
with ultra-rare bone disorders and other diseases with high medical
need. The company is preparing for a 2019 new drug application (NDA)
submission to the FDA to seek approval of its lead product candidate,
palovarotene, a novel RARγ agonist, for the prevention of heterotopic
ossification (HO) associated with flare up symptoms in adults and
children with fibrodysplasia ossificans progressiva (FOP). The ongoing
Phase 3 MOVE Trial is evaluating an additional dosing regimen of
palovarotene for the treatment of FOP. Palovarotene is also in a Phase 2
trial, the MO-Ped Trial, for the treatment of multiple osteochondromas
(MO, also known as multiple hereditary exostoses, or MHE). In addition,
Clementia has commenced a Phase 1 trial for an eye drop formulation of
palovarotene for the potential treatment of dry eye disease and is also
investigating other conditions that may benefit from RARγ therapy. For
more information, please visit www.clementiapharma.com
and connect with us on Twitter @ClementiaPharma.

Forward Looking Statement

This press release may include “forward-looking statements” within the
meaning of the applicable securities laws, including with respect to the
proposed timing of filings and submissions with the FDA for palovarotene
and the impact of the transaction on Ipsen and Clementia, the operations
of Ipsen and Clementia post-transaction and the amounts potentially
payable under the CVRs. Each forward-looking statement contained in this
press release is subject to known and unknown risks and uncertainties
and other unknown factors that could cause actual results to differ
materially from historical results and those expressed or implied by
such statement. In addition to statements which explicitly describe such
risks and uncertainties, readers are urged to consider statements
labeled with the terms “believes,” “belief,” “expects,” “intends,”
“anticipates,” “will,” or “plans” to be uncertain and forward-looking.
Applicable risks and uncertainties include, among others, the outcome of
the FDA approval of palovarotene product candidate for the treatment of
multiple osteochondromas (MO), Clementia’s ability to successfully
complete in a timely manner the studies required to be completed in
order to submit the NDA, Clementia’s ability to generate revenue and
become profitable, the risks related to its heavy reliance on
palovarotene, its only current product candidate, the risks associated
with the development of palovarotene and any future product candidate,
including the demonstration of efficacy and safety, Ipsen’s and
Clementia’s dependence on licensed intellectual property, including the
ability to source and maintain licenses from third-party owners; as well
as the risks identified in Ipsen’s registration documents filed with the
French Autorité des Marchés Financiers and Clementia’s public
filings with the SEC and the Québec Autorité des Marchés Financiers.
Ipsen and Clementia caution investors not to rely on the forward-looking
statements contained in this press release when making an investment
decision in their securities. Investors are encouraged to read Ipsen’s
filings available on its website (www.ipsen.com)
as well as Clementia’s filings with the SEC or on SEDAR, available at www.sec.gov
or www.sedar.com,
for a discussion of these and other risks and uncertainties. The
forward-looking statements in this press release speak only as of the
date of this press release, and Ipsen and Clementia undertake no
obligation to update or revise any of these statements, whether as a
result of new information, future events or otherwise, except as
required by law.

Contacts

For further information

Media
Karla MacDonald –
North America
Vice President, NA Communications
+ 1 (857)
332-3467
[email protected]

Monique Allaire
President, THRUST Strategic Communications
+
1 (781) 631-0759
[email protected]

Christian Marcoux – Europe
Senior
Vice-President, Global Communication
+33 (0) 1 58 33 67 94
[email protected]

Joseph Walewicz
EVP, Business and Corporate Development
+1
(514) 940-1080
[email protected]

Financial Community
Eugenia
Litz
Vice President, Investor Relations
+44 (0) 7879 627
205
[email protected]

Myriam Koutchinsky
Investor Relations Manager
+33 (0)1
58 33 51 04
[email protected]