Exhibit 99(a)
                              BDNF PHASE 3 TRIAL
                         DOES NOT DEMONSTRATE EFFICACY

FOR IMMEDIATE RELEASE

THOUSAND OAKS, Calif., January 10, 1997 -- Amgen (NASDAQ:AMGEN) and Regeneron
Pharmaceuticals, Inc. (NASDAQ:REGN) today announced that the Phase 3 clinical
trial of Brain-Derived Neurotrophic Factor (BDNF) did not demonstrate clinical
efficacy in patients with amyotrophic lateral sclerosis (ALS), commonly known
as Lou Gehrig's Disease.

While the trial confirmed the safety and tolerability seen in earlier trials,
it showed no statistically significant or clinically relevant difference in
breathing capacity or survival between treatment and placebo groups. Breathing
capacity was measured by forced vital capacity (F VC), a reliable measure of
respiratory function and an established clinical indicator in this
neurodegenerative disorder.

The trial was designed to evaluate effects of subcutaneous delivery of BDNF for
ALS. Small, early-stage clinical trails investigating intrathecal
administration for ALS and subcutaneous delivery for diabetic neuropathy are in
progress and will continue. However, no further development of subcutaneous
delivery for ALS is planned.

"Obviously, we are disappointed with these results," said Gordon Binder,
chairman and chief executive officer of Amgen. "We had hoped that this trial 
would show benefit for patients with this tragic disease. We thank the patients
and health care professionals who participated in the trial."

Leonard S. Schleifer, M.D., Ph.D., president and chief executive officer of
Regeneron, also stressed his great disappointment. "Nevertheless," Schleifer
said, "we continue to believe that neurotrophic factors have potential to
benefit patients with neurological diseases. Thus, we will continue our pursuit
of intrathecal use of BDNF in patients with ALS and both BDNF and NT-3 for
treatment of peripheral neuropathies."

Amgen is a global biotechnology company that discovers, develops, manufactures
and markets human therapeutics based on advances in cellular and molecular
biology.

Regeneron (NASDAQ:REGN), based in Tarrytown, N.Y., is a leader in the
application of molecular and cell biology to discover novel potential therapies
for human medical conditions. The Company is applying its technological
expertise in protein growth factors, their receptors and their mechanisms of
action to the discovery and development of neurotrophic factors for the
potential treatment of neurodegenerative diseases, peripheral neuropathies and
nerve injury. More recently, Regeneron has used its technological expertise to
attempt to identify treatments for diseases and conditions outside of the
nervous system, such as inflammatory and muscle diseases, angiogenesis,
hematopoiesis, and cancer.

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Amgen and Regeneron are jointly developing two neurotrophic factors, BDNF and
NT-3.

CONTACT: David Kaye, Amgen, 805/447-6692 (media)
         Denise Powell, Amgen, 805/447-4346 (investors)
         Murray Goldberg, Regeneron, 914/345-7492 (media/investors)

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NOTE:    For additional information, health care professionals and patients
can contact Amgen at 1-800-772-6436 or the ALS Association at 1-800-782-4747.

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