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Exhibit 99.1


FOR IMMEDIATE RELEASE
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Contact at Interneuron:
    Michael W. Rogers                                William B. Boni
    Executive VP and Chief Financial Officer         VP, Corp. Communications
    (781) 861-8444                                   (781) 402-3410


                INTERNEURON OBTAINS MAJORITY OWNERSHIP OF CPEC

               CPEC Has Worldwide License of BEXTRA(R) (Bucindolol)

                         For Congestive Heart Failure

LEXINGTON, MA, July 16, 1999 -- Interneuron Pharmaceuticals, Inc. (NASDAQ: IPIC)
today announced that it entered into a series of agreements that result in
Interneuron owning 65 percent of CPEC LLC, which is developing BEXTRA
(bucindolol) for congestive heart failure. In exchange, Interneuron returned to
Intercardia, Inc. (NASDAQ: ITRC), previously a majority-owned subsidiary of
Interneuron, approximately 4.2 million of the 4.5 million shares of Intercardia
common stock owned by Interneuron.

CPEC has an exclusive worldwide license from Bristol-Myers Squibb Company to
develop and commercialize BEXTRA for congestive heart failure and is currently
supporting, with the National Institutes of Health (NIH) and Department of
Veterans Affairs (VA), a 2,708-patient Phase 3 clinical trial with bucindolol in
the U.S.  CPEC has licensed to BASF Pharma/Knoll AG commercialization rights to
BEXTRA outside the United States and Japan, and BASF/Knoll is conducting a Phase
3 clinical trial with the drug in Europe.

Interneuron and Intercardia will now assume 65 percent and 35 percent,
respectively, of CPEC's funding requirements for the development of BEXTRA in
the U.S. and Japan and will be entitled to 65 percent and 35 percent,
respectively, of the profits and available cash of CPEC LLC. Intercardia will
assume all funding obligations and rights in the territory covered by the Knoll
license. In return, Interneuron will be entitled to a percentage of net sales of
BEXTRA in the Knoll territory.

"This transaction is based upon the respective business strategies of
Interneuron and Intercardia," said Glenn L. Cooper, M.D., president and chief
executive officer of Interneuron. "Interneuron is engaged principally in the
development of advanced stage products, including BEXTRA, citicoline (for
ischemic stroke), and pagoclone (for panic and general anxiety disorders), while
Intercardia also has a significant interest in earlier clinical candidates and
discovery research programs.
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"We believe that BEXTRA has the potential to contribute meaningfully to the
treatment options for CHF, the only cardiovascular disease actually growing in
incidence in the U.S.," said Dr. Cooper. "As a nonselective beta-blocker with
mildly vasodilating properties, BEXTRA may be of particular benefit to patients
with this debilitating disease."

The board of directors of CPEC will consist of three members designated by
Interneuron and two by Intercardia.  Dr. Cooper resigned as chairman of the
board and director of Intercardia and became chairman of the board of CPEC. A
committee composed of representatives of Interneuron and Intercardia will
oversee development of bucindolol.

Prior to these transactions, Interneuron owned approximately 61 percent of
Intercardia's common stock and approximately 20 percent of CPEC, Inc., the
predecessor to CPEC LLC. Intercardia previously owned approximately 80 percent
of CPEC, Inc. Interneuron now owns approximately 9 percent of Intercardia's
outstanding common stock, representing shares payable to Interneuron as part of
the May 1998 sale of Transcell Technologies, Inc. to Intercardia. Interneuron
retains the right to receive additional shares of Intercardia common stock as
the final installment of the Transcell merger consideration in February 2000.

As a result of these transactions, Interneuron will no longer consolidate
Intercardia's financial statements but will instead consolidate CPEC's financial
statements.  Interneuron will record noncash charges to operations of
approximately $2 million to $4 million relating to these transactions in fiscal
1999.

The ongoing Phase 3 Beta-blocker Evaluation of Survival Trial (BEST), under the
sponsorship of the NIH and the VA, is assessing the effect on mortality of the
addition of treatment with BEXTRA to traditional therapy for patients suffering
from moderate to severe congestive heart failure.  Enrollment in BEST ended in
December 1998, with 2,708 patients.

Interneuron Pharmaceuticals is engaged in the development and commercialization
of a portfolio of products and product candidates for central nervous system,
cardiovascular and other disorders, including multiple compounds in late-stage
clinical development.

Except for the descriptions of historical facts contained herein, this press
release contains forward-looking statements that involve risks and uncertainties
that could cause the Company's actual results and financial condition to differ
materially from those anticipated by the forward looking statements. These risks
and uncertainties are set forth in the Company's filings under the Securities
Act of 1933 and the Securities Exchange Act of 1934 under "Risk Factors" and
elsewhere, and include, but are not limited to, risks relating to the Redux-
related litigation, including risk relating to the finalization of the proposed
settlement of the product liability litigation; uncertainties relating to
clinical trials and regulatory approvals; need for additional funds and
corporate partners; history of operating losses and expectation of future
losses; product liability; dependence on third parties for manufacturing and
marketing; the early stage of products under development; government regulation,
patent risks and competition.