UPDATE 2-Regeneron pain drug put on clinical hold by FDA

* FDA places osteoarthritis pain drug on clinical hold

* Follows safety concern in another company’s trial

* FDA believes problem is due to class effect
(Updates with share price, additional background)

By Toni Clarke

BOSTON, Dec 27 (BestGrowthStock) – Regeneron Pharmaceuticals Inc
(REGN.O: ) said on Monday that U.S. regulators placed the
company’s experimental pain drug for osteoarthritis on clinical
hold after a patient in another company’s trial developed a
serious bone disorder.

Regeneron said it and its partner, Sanofi-Aventis SA
(SASY.PA: ), were informed late last week by the U.S. Food and
Drug Administration that the drug, REGN475/SAR164877, was being
placed on clinical hold after a patient in another company’s
trial developed avascular necrosis of a joint.

The condition is caused when bone tissue dies due to lack
of blood supply, eventually causing the bone to collapse.

Regeneron’s drug is designed to work by blocking a protein
called nerve growth factor (NGF) that is associated with pain.
An NGF-inhibitor under development by Pfizer Inc (PFE.N: ) was
put on hold earlier this year after some patients required
joint replacement surgery.

The FDA believes its safety concerns could affect the
entire anti-NGF class.

Decision Resources, a healthcare advisory firm, had
originally projected peak global sales of Pfizer’s drug
tanezumab could reach $1.2 billion, but reduced that forecast
to $200 million after it was placed on clinical hold.

Tanezumab was the most advanced in the class and its
setback cast a cloud over other drugs in development, including
Regeneron’s. Johnson & Johnson (JNJ.N: ) and Abbott Laboratories
(ABT.N: ) each have early stage anti-NGF programs.

Shares of Regeneron fell 0.7 percent to $33.27 in
mid-morning trading on Nasdaq, in line with a 0.6 percent
decline in the Nasdaq Biotech Index (.NBI: ).

Regeneron said there are currently no trials with the drug
that are enrolling or treating patients.
(Reporting by Toni Clarke; Editing by Derek Caney, Dave
Zimmerman)

UPDATE 2-Regeneron pain drug put on clinical hold by FDA