1

                              [CELTRIX LETTERHEAD]


NEWS RELEASE



                              CONTACT: Andreas Sommer, Ph.D.
                                       President and Chief Executive Officer
                                       (408) 988-2500


               CELTRIX SUBSTANTIALLY BOLSTERS ITS PATENT PORTFOLIO

     SAN JOSE, CA -- February 18, 1999 -- Celtrix Pharmaceuticals, Inc. (Nasdaq:
CTRX) announced today that it has received a Notice of Allowance from the U.S.
Patent and Trademark Office on a key patent application relating to therapeutic
delivery of its lead product candidate, SomatoKine(R) (IGF-I/BP3 complex). The
allowed patent claims specific methods of delivering effective doses of IGF-I
using SomatoKine to treat any indication.

     The allowed claims of this patent application cover IGF-I dose levels which
the company has tested in several recently completed Phase II clinical
feasibility studies. The allowed claims cover routes of administration and
delivery techniques that may be desirable alternatives to frequent subcutaneous
injections.

     "What is particularly exciting about this patent is the breadth of its
claims, specifically the coverage of all indications," commented Andreas Sommer,
Ph.D., Celtrix's president and chief executive officer. "Whereas Celtrix already
owns specific intellectual property relating to the systemic treatment of
osteoporosis, catabolic diseases, wound healing, trauma, burns, as well as
certain hematologic and renal indications, this new patent claims the use of
SomatoKine to deliver IGF-I at dose levels that the company believes are
necessary for efficacy. In earlier Phase I clinical safety studies and in
several recently completed Phase II clinical feasibility studies, the company
has demonstrated that such dose levels can be safely administered using its
SomatoKine technology."

     Celtrix has also added other patents to its portfolio in recent months:
U.S. patents covering various aspects of a manufacturing process for SomatoKine;
the use of SomatoKine for the treatment of certain renal disorders; and a method
for predicting how a patient will respond to SomatoKine. Celtrix currently owns
19 issued or allowed U.S. patents, and 21 families of patent applications
relating to the composition, production, diagnostics and methods of therapeutic
use for SomatoKine.

THE SOMATOKINE COMPLEX

     SomatoKine is the recombinant equivalent of the natural complex formed by
the hormone insulin-like growth factor-I (IGF-I) and its major regulatory
binding protein (BP3). IGF-I plays multiple roles in diverse biological
processes, including preservation and formation of bone and muscle. IGF-I also
plays a key role in the control of blood glucose. BP3 contains biological
information important for the body's natural regulation of IGF-I bioavailability
and biodistribution. Administration of SomatoKine, the IGF-I/BP3 complex,
establishes a circulating reservoir of IGF-I that is proving in clinical
research to be both safe and effective.


                                     -more-


   2

"Celtrix Substantially Bolsters Its Patent Portfolio"
Page 2


ADDITIONAL INFORMATION

     Celtrix is a biopharmaceutical company developing therapeutics for
seriously debilitating, degenerative conditions primarily associated with severe
trauma, chronic diseases or aging. The company's focus is on SomatoKine, the
novel IGF-I/BP3 complex, for treatment of a broad range of metabolic disorders.
Celtrix has recently completed Phase II feasibility trials in severely
osteoporotic patients recovering from hip fracture surgery and patients
undergoing treatment for traumatic burns. The company has nearly completed Phase
II clinical testing for the treatment of diabetes. Celtrix has also licensed
rights for development of another molecule, TGF-beta-2, to Genzyme Corporation
for incorporation into their comprehensive program for tissue repair. TGF-beta-2
is currently in Phase II clinical testing for treatment of dermal ulcers.

     This news release contains certain forward-looking statements within the
meaning of Section 21E of the Securities Exchange Act of 1934, as amended.
Actual results may differ materially from the statements made, as a result of
various factors, including risks associated with the issuance and continuation
of the patents referred to in this press release, ability of the company to
enter into a collaboration with a corporate partner for the continuation of the
clinical trials, that such trials will continue to show the same observations,
including any statistically relevant results in larger Phase II or Phase III
trials, as well as risks associated with future research, the regulatory
approval process, competitive products and other factors which are listed from
time to time in Celtrix's Securities and Exchange Commission (SEC) filings.
These forward-looking statements represent Celtrix's judgment as of the date of
this news release.

                                      -end-