Preliminary Data from Servier and Pfizer's UCART19 Product Candidate Shows High Complete Remission Rate Across Two Phase I Adult and Pediatric Acute Lymphoblastic Leukemia Trials NEW YORK--(BUSINESS WIRE)

Data from Servier and Pfizer's UCART19 Product Candidate Shows High

Complete Remission Rate Across Two Phase I Adult and Pediatric Acute

Lymphoblastic Leukemia Trials

NEW YORK--(BUSINESS WIRE)--December 12, 2017--Regulatory News:

Servier, Pfizer Inc. (NYSE: PFE) and Cellectis

(Paris:ALCLS) (NASDAQ:CLLS) (Euronext Growth: ALCLS - Nasdaq: CLLS)

presented at the 59th American Society of Hematology (ASH) Annual

Meeting and Exposition in Atlanta preliminary results from two phase

1 studies of UCART19, an investigational allogeneic anti-CD19 CAR T-cell

product, in adult and pediatric patients with relapsed or refractory

(R/R) CD19-positive B-cell acute lymphoblastic leukemia (B-ALL). These

first-in-human data demonstrated the safety and tolerability of UCART19,

resulting in an 83% complete remission rate across the adult and

pediatric patient population.

Results from the CALM (UCART19 in Advanced Lymphoid

The CALM study (UCART19 in Advanced Lymphoid Malignancies)

is an open label, dose-escalation study designed to evaluate the safety,

tolerability and anti-leukemic activity of UCART19 in adult patients

with R/R B-ALL. Five out seven patients treated achieved molecular

remission at Day 28 post UCAR19. Molecular remission is defined by

negative minimal residual disease (MRD). MRD is a measurement of the

number of residual leukemic cells that remain after treatment.

"These early results for UCART19 are very encouraging both in terms of

manageable safety and the impressive complete molecular remission rate

in these hard-to-treat adult patients with R/R B-ALL," said Reuben

Benjamin, Principal Investigator of the CALM Study and Consultant

Hematologist at King's College Hospital, United Kingdom. "This first

cohort explored a lower dose of UCART19 that is approximately one tenth

of that used in most autologous CAR-T trials. These results support

additional evaluation of UCART19 at varying doses."

Only one Grade 1 cutaneous acute graft versus host disease (GvHD)

occurred. No severe neurotoxicity was observed. Cytokine release

syndromes (CRS) were mild and manageable except in one patient treated

with UCART19 at the first dose level, who developed CRS Grade 4 and

neutropenic sepsis leading to death at Day 15.

Results from the PALL (Pediatric Acute Lymphoblastic

The PALL (Pediatric Acute Lymphoblastic Leukemia)

study is a phase 1, open label study designed to evaluate the safety and

ability of UCART19 to induce molecular remission defined by MRD

negativity at Day 28 to enable allogeneic stem cell transplantation in

pediatric patients with high-risk R/R B-ALL. Results showed all five

children achieved MRD negativity, enabling them to proceed to allogeneic

stem cell transplant. Only one Grade 1 cutaneous acute GvHD occurred. No

severe neurotoxicity was observed. Cytokine release syndromes were mild

in the majority of cases and were all manageable.

Servier is the sponsor of both studies that are active in Europe and the

"We are proud to present the first clinical trial data with UCART19 in

patients with heavily pretreated R/R ALL," said Patrick Therasse, MD,

PhD, Head of Research and Development-Oncology for Servier. "We believe

this innovative, allogeneic CAR T-cell approach could be disruptive to

the patient community."

UCART19 is an allogeneic CAR T-cell product candidate being developed

for treatment of CD19-expressing hematological malignancies, gene edited

with TALEN . UCART19 is initially being developed in adult and pediatric

ALL and is currently in Phase I. UCART19 has the potential to overcome

the limitation of the current autologous approach by providing an

allogeneic, frozen, "off-the-shelf" T cell based medicinal product.

In November 2015, Servier acquired the exclusive rights to UCART19 from

Cellectis. Following further agreements, Servier and Pfizer began

collaborating on a joint clinical development program for this cancer

immunotherapy. Pfizer has been granted exclusive rights by Servier to

develop and commercialize UCART19 in the United States, while Servier

retains exclusive rights for all other countries.

Servier is an international pharmaceutical company governed by a

non-profit foundation, with its headquarters in France (Suresnes). With

a strong international presence in 148 countries and a turnover of 4

billion euros in 2016, Servier employs 21 000 people worldwide. Entirely

independent, the Group reinvests 25% of its turnover (excluding generic

drugs) in research and development and uses all its profits for

development. Corporate growth is driven by Servier's constant search for

innovation in five areas of excellence: cardiovascular,

immune-inflammatory and neuropsychiatric diseases, cancers and diabetes,

as well as by its activities in high-quality generic drugs.

Becoming a key player in oncology is part of Servier's long-term

strategy. Currently, there are nine molecular entities in clinical

development in this area, targeting gastric and lung cancers and other

solid tumors, as well as various leukemias and lymphomas. This portfolio

of innovative cancer treatments is being developed with partners

worldwide, and covers different cancer hallmarks and modalities,

including cytotoxics, proapoptotics, targeted, immune and cellular

therapies, to deliver life-changing medicines to patients. More

information: https://servier.com.

Pfizer Inc.: Working together for a healthier world

At Pfizer, we apply science and our global resources to bring therapies

to people that extend and significantly improve their lives. We strive

to set the standard for quality, safety and value in the discovery,

development and manufacture of health care products. Our global

portfolio includes medicines and vaccines as well as many of the world's

best-known consumer health care products. Every day, Pfizer colleagues

work across developed and emerging markets to advance wellness,

prevention, treatments and cures that challenge the most feared diseases

of our time. Consistent with our responsibility as one of the world's

premier innovative biopharmaceutical companies, we collaborate with

health care providers, governments and local communities to support and

expand access to reliable, affordable health care around the world. For

more than 150 years, we have worked to make a difference for all who

rely on us. We routinely post information that may be important to

investors on our website at www.pfizer.com. In addition, to learn

at @Pfizer and @Pfizer_News, LinkedIn, YouTube, and like us on Facebook

at Facebook.com/Pfizer.