Tranzyme Pharma and Ocera Therapeutics Announce Merger Agreement

Tranzyme Pharma and Ocera Therapeutics Announce Merger Agreement

              $20M Committed PIPE Financing to Close With Merger

     – Joint Conference Call Scheduled for April 24, 2013 at 8:00am ET –

RESEARCH TRIANGLE PARK, N.C. and SAN DIEGO, April 23, 2013 (GLOBE NEWSWIRE) --
Tranzyme Pharma (Nasdaq:TZYM) ("Tranzyme"), a biopharmaceutical company
focused on discovering, developing and commercializing novel, mechanism-based
therapeutics, and Ocera Therapeutics, Inc. ("Ocera"), a privately held
biopharmaceutical company developing novel therapeutics for liver diseases,
today announced that they have entered into a definitive agreement under which
Ocera will merge with a subsidiary of Tranzyme in an all-stock transaction.
The merger is expected to create a NASDAQ-listed company focused on the
development of novel therapeutics for patients with acute and chronic
decompensated liver disease, an area of high unmet medical need. Upon closing,
the company will be named "Ocera Therapeutics, Inc." (the "Company").

Concurrently with the execution of the merger agreement, the Ocera investor
syndicate committed to a $20 million PIPE financing for the Company, which
will close with the merger. All of Ocera's largest preferred stock investors,
including Domain Associates, Thomas McNerney & Partners, Sofinnova Ventures
and InterWest Partners, have committed to participate in the PIPE financing.

"Following an extensive and thorough review of strategic alternatives, we
believe the proposed merger with Ocera offers the best value for our
stockholders", said Vipin K. Garg, PhD, Tranzyme's President and Chief
Executive Officer. "We expect the merger will benefit from the substantial
synergies of the combined management team's extensive experience in drug
development, specifically in hepatology, which will help accelerate the
transition and allow for efficient execution of the development plan."

Linda Grais, MD, President and Chief Executive Officer of Ocera, stated, "The
merger and concurrent financing will allow the Company to continue to advance
Ocera's lead clinical program, OCR-002, a differentiated product candidate for
orphan liver diseases currently in Phase 2 development. This product candidate
addresses a significant unmet need in the treatment of acute hepatic
encephalopathy, and we look forward to the initiation of our Phase 2b trial
later this year and additional Phase 2a data in 2014."

OCR-002 has received Orphan Drug designation in the United States and Europe
and has been granted fast track status by the U.S. Food and Drug
Administration. We estimate that there are up to one million patients with
cirrhosis in the United States, and approximately 150,000 hospitalizations
occur annually due to complications of encephalopathy, costing the healthcare
system approximately $7 billion every year. For more information about
clinical trials related to OCR-002, please visit: www.clinicaltrials.gov.

Details of the Proposed Transaction

On a pro forma basis, prior to the financing transaction discussed below,
based upon the number of shares of Tranzyme common stock to be issued in the
merger, current Tranzyme shareholders will own approximately 27.4% of the
Company and current Ocera shareholders will own approximately 72.6% of the
Company. The final number of shares will be subject to adjustments at closing
based on each company's cash levels and other matters at closing. The
transaction has been unanimously approved by the board of directors of both
companies. The merger is expected to close in the third quarter of 2013,
subject to approval by a majority of Tranzyme stockholders, review by the
Securities and Exchange Commission and customary closing conditions as
detailed in the merger agreement.

Concurrently with the execution of the merger agreement, Tranzyme entered into
a securities purchase agreement pursuant to which certain investors agreed to
purchase, and it agreed to sell, $20 million worth of its common stock at a
price to be determined based on the weighted average trading price of
Tranzyme's closing price for the 10 days prior to the closing of the merger.
The securities purchase agreement is conditioned on closing of the merger
transaction and customary closing conditions as detailed in the securities
purchase agreement, and contains customary representations, warranties,
covenants and indemnities.

In connection with the merger, Tranzyme plans to effect a reverse stock split
intended to increase its trading price to above the minimum requirements of
Nasdaq for allowing the company to remain listed following the transaction.
Whether Tranzyme will remain listed following the transaction depends on
whether Tranzyme will satisfy all of the applicable Nasdaq requirements.

Stifel served as financial advisor, Goodwin Procter LLP served as legal
counsel to Tranzyme and Skadden, Arps, Slate, Meagher & Flom LLP served as
legal counsel to the special committee and the board of directors of Tranzyme
with respect to the transaction. Reed Smith LLP served as legal counsel to
Ocera with respect to the transaction.

Management and Organization

Following the merger, the Company will be headed by Linda Grais, MD, the
current President and CEO of Ocera. The corporate headquarters will be located
in San Diego, California. Clinical and regulatory operations will be led by
Franck S. Rousseau, MD, Chief Medical Officer of Tranzyme, in the existing
office in Research Triangle Park, North Carolina. The board of directors will
be comprised of representatives from both the existing Ocera and Tranzyme
companies, including Drs. Grais and Rousseau.

Upon completion of the merger, Dr. Vipin K. Garg, Tranzyme's President and CEO
will depart the Company to pursue other interests.

About OCR-002

OCR-002 (ornithine phenylacetate) is an ammonia scavenger designed to treat
hyperammonemia and associated hepatic encephalopathy in patients with liver
cirrhosis, acute liver failure and acute liver injury. OCR-002, through its
dual mechanism of action, directly lowers circulating blood levels of ammonia
by enabling alternate metabolic pathways in the muscle and kidney in patients
with decompensated liver cirrhosis, and or liver failure from other causes.
OCR-002 is being developed as an injectable formulation for hospitalized
patients and as an oral formulation to treat and prevent recurrences of
hepatic encephalopathy. Hepatic encephalopathy is an often-reversible
neuropsychiatric abnormality observed in patients with liver disease; it is
marked by a worsening of brain function when the liver is no longer able to
remove toxic substances such as ammonia in the blood. Ammonia accumulation in
the blood impairs brain cell function. Signs of hepatic encephalopathy include
impaired cognition, uncontrolled movements and decreased levels of
consciousness leading to coma and death due to brain swelling.

Planning is underway to initiate a Company-sponsored Phase 2b, randomized,
double-blind, placebo-controlled, efficacy study of OCR-002 as a treatment for
acute hepatic encephalopathy in hospitalized patients with liver cirrhosis.
Enrollment is expected to begin in late 2013.

OCR-002 also is the subject of two ongoing, externally-sponsored, Phase 2a
studies in patients. Data from these studies are expected in 2014.

Conference Call Wednesday, April 24, 2013 at 8:00am ET

Tranzyme and Ocera will host a joint conference call on Wednesday, April 24,
2013 at 8:00am ET to discuss the planned merger and its business overview. To
participate in the live call, please dial (877) 670-9784 (U.S. and Canada) or
(970) 315-0430 (international), five to ten minutes prior to the start of the
call. A live audio webcast will also be available in the "Investors" section
of the Tranzyme website, www.tranzyme.com. A replay of the conference call and
archived version of the webcast will be made available once a transcript has
been filed with the SEC, and we expect the replay to remain available until
April 30, 2013. Investors will be able to listen to the replay by dialing
(855) 859-2056 (U.S. and Canada) or (404) 537-3406 (international) with the
passcode 38813485 and the webcast will be archived at www.tranzyme.com.

About Tranzyme Pharma

Tranzyme Pharma is a biopharmaceutical company focused on discovering,
developing and commercializing novel, mechanism-based therapeutics. All of
Tranzyme's drug discovery activities are based on its proprietary small
molecule macrocyclic template chemistry (MATCH™) technology, which has also
been successfully used to generate drug candidates in partnership with other
pharmaceutical companies. MATCH enables the rapid construct of synthetic
libraries of drug-like, macrocyclic compounds in a predictable and efficient
manner. By leveraging MATCH, Tranzyme is committed to pursuing first-in-class
medicines to address areas of significant unmet medical need and continues to
pursue funded drug discovery partnerships. Additional information on Tranzyme
can be found at www.tranzyme.com.

About Ocera Therapeutics, Inc.

Ocera Therapeutics, based in San Diego, California, is a privately held
biopharmaceutical company focused on the development and commercialization of
proprietary compounds to treat acute and chronic liver diseases. In addition
to OCR-002, Ocera has developed Zysa™ (AST-120) a spherical carbon adsorbent,
for the treatment of irritable bowel syndrome. Ocera has raised over $60
million dollars in venture financing from funds including Domain Associates,
Sofinnova Ventures, Thomas, McNerney & Partners, Greenspring Associates and
InterWest Partners. Additional information on Ocera can be found at
www.ocerainc.com.

Cautionary Note Regarding Forward-Looking Statements

Certain statements in this communication regarding the proposed merger and
other contemplated transactions (including statements relating to satisfaction
of the conditions to and consummation of the proposed merger, the expected
ownership of the combined company, the alternatives to the proposed merger,
and plans with respect to financing for the combined company) constitute
"forward-looking statements" within the meaning of Section 27A of the
Securities Act and Section 21E of the Securities Exchange Act and are usually
identified by the use of words such as "anticipates," "believes," "estimates,"
"expects," "intends," "may," "plans," "projects," "seeks," "should," "will,"
and variations of such words or similar expressions. We intend these
forward-looking statements to be covered by the safe harbor provisions for
forward-looking statements contained in Section 27A of the Securities Act and
Section 21E of the Securities Exchange Act and are making this statement for
purposes of complying with those safe harbor provisions. These forward-looking
statements reflect our current views about our plans, intentions,
expectations, strategies and prospects, which are based on the information
currently available to us and on assumptions we have made. Although we believe
that our plans, intentions, expectations, strategies and prospects as
reflected in or suggested by those forward-looking statements are reasonable,
we can give no assurance that the plans, intentions, expectations or
strategies will be attained or achieved. Furthermore, actual results may
differ materially from those described in the forward-looking statements and
will be affected by a variety of risks and factors that are beyond our
control.

Risks and uncertainties for Tranzyme and Ocera and of the combined company
include, but are not limited to: inability to complete the proposed merger and
other contemplated transactions; liquidity and trading market for shares prior
to and following the consummation of the proposed merger and proposed
financing; costs and potential litigation associated with the proposed merger;
failure or delay in obtaining required approvals by the SEC or any other
governmental or quasi-governmental entity necessary to consummate the proposed
merger, including our ability to file an effective proxy statements in
connection with the proposed merger and other contemplated transactions, which
may also result in unexpected additional transaction expenses and operating
cash expenditures on the parties; inability or the delay in obtaining required
regulatory approvals for product candidates, and/or which may result in
unexpected cost expenditures; failure to issue Tranzyme common stock in the
proposed merger and other contemplated transactions exempt from registration
or qualification requirements under applicable state securities laws; the
price of the financing transaction in connection with the proposed merger and
contemplated transactions being materially lower than the current weighted
average trading price of Tranzyme's common stock, or the aggregate amount of
cash received from such financing transaction being less than anticipated;
uncertainties in obtaining successful clinical results for product candidates
and unexpected costs that may result therefrom; failure to realize any value
of certain product candidates developed and being developed, including with
respect to OCR-002, in light of inherent risks and difficulties involved in
successfully bringing product candidates to market; inability to develop new
product candidates and support existing products; the approval by the FDA and
EMA and any other similar foreign regulatory authorities of other competing or
superior products brought to market; risks resulting from unforeseen side
effects; risk that the market for the combined company's products may not be
as large as expected; inability to obtain, maintain and enforce patents and
other intellectual property rights or the unexpected costs associated with
such enforcement or litigation; inability to obtain and maintain commercial
manufacturing arrangements with third party manufacturers or establish
commercial scale manufacturing capabilities; loss of or diminished demand from
one or more key customers or distributors; unexpected cost increases and
pricing pressures; continuing or deepening economic recession and its negative
impact on customers, vendors or suppliers; failure to obtain the necessary
stockholder approvals or to satisfy other conditions to the closing of the
proposed merger and the other contemplated transactions; a superior proposal
being submitted to either party; uncertainties of cash flows and inability to
meet working capital needs; cost reductions that may not result in anticipated
level of cost savings or cost reductions prior to or after the consummation of
the proposed merger; and risks associated with the possible failure to realize
certain benefits of the proposed merger, including future financial, tax,
accounting treatment, and operating results. Many of these factors that will
determine actual results are beyond Tranzyme's, Ocera's, or the combined
company's ability to control or predict.

Other risks and uncertainties are more fully described in our Annual Report on
Form 10-K for the year ended December 31, 2012 filed with the SEC, and in
other filings that Tranzyme makes and will make with the SEC in connection
with the proposed transactions, including the proxy statement described below
under "Important Information and Where to Find It." Existing and prospective
investors are cautioned not to place undue reliance on these forward-looking
statements, which speak only as of the date hereof.The statements made in
this press release speak only as of the date stated herein, and subsequent
events and developments may cause our expectations and beliefs to change.
While we may elect to update these forward-looking statements publicly at some
point in the future, we specifically disclaim any obligation to do so, whether
as a result of new information, future events or otherwise, except as required
by law. These forward-looking statements should not be relied upon as
representing our views as of any date after the date stated herein.

Important Information and Where to Find It

Tranzyme and Ocera and certain of their directors and executive officers may
become participants in solicitation of proxies from Tranzyme stockholders in
connection with the proposed transactions. Additional Information regarding
persons who may, under the rules of the SEC, be deemed to be participants in
the solicitation of the Tranzyme stockholders in connection with the proposed
merger, and who have interests, whether as security holders, directors or
employees of Tranzyme or Ocera or otherwise, which may be different from those
of Tranzyme stockholders generally, will be provided in the proxy statement
and other materials to be filed with the SEC.

Each of Tranzyme's board of directors, John H. Johnson, George B. Abercrombie,
Jean-Paul Castaigne, Vipin K. Garg, Anne M. VanLent, and Alex Zisson;
Tranzyme's executive officers, Vipin K. Garg (President and Chief Executive
Officer), Franck Rousseau (Chief Medical Officer), David Moore (Chief Business
Officer) and Helmut Thomas (Senior Vice President, Research and Preclinical
Development); Ocera's board of directors, Eckard Weber, Lars Ekman, Linda
Grais, Nina Kjellson, Michael F. Powell, and Pratik Shah; and Ocera's
executive officers, Linda Grais (Chief Executive Officer), Dana S. McGowan
(Chief Financial Officer and Secretary) and Keith Anderson (Vice President
Pharmaceutical Sciences and Chief Operating Officer); may be deemed
"participants" in the solicitation of proxies from the Tranzyme stockholders
in connection with the proposed transactions.

Information regarding Tranzyme's directors' and executive officers' respective
interests in Tranzyme by security holdings or otherwise is set forth in
Tranzyme's proxy statement relating to the 2012 annual meeting of stockholders
filed with the SEC on April 27, 2012.The following is a list of the current
approximate number of shares of Tranzyme common stock beneficially held by
each of the foregoing Tranzyme directors and officers listed above: John H.
Johnson (66,835 shares), George B. Abercrombie (50,468 shares), Jean-Paul
Castaigne (51,545 shares), Vipin K. Garg (689,068 shares), Anne M. VanLent
(50,468 shares), Alex Zisson (50,468 shares), Franck Rousseau (90,625 shares),
David Moore (69,800 shares) and Helmut Thomas (119,105 shares).

Vipin Garg, Tranzyme's President and Chief Executive Officer, will be entitled
to receive severance pay in the aggregate amount of approximately $450,000 and
the acceleration of the vesting of all outstanding stock awards along with
other separation benefits upon the termination of his employment at the
closing of the proposed merger.Alex Zisson, a Tranzyme director, and Pratik
Shah, an Ocera director, are each partners at, and director appointees of,
Thomas McNerney & Partners, LLC and its affiliates ("TMP").TMPbeneficially
owns an aggregate of approximately 12,933,146 shares of Ocera stock after
giving effect to the exercise of certain options and warrants, the conversion
of convertible notes of Ocera into preferred stock of Ocera (assuming a
closing date of June 30, 2013), and the conversion of those shares and all
other shares of preferred stock beneficially owned by TMP into common stock.
It is anticipated that Dr. Shah will be a director of the combined company
following the consummation of the proposed merger. Dr. Shah would be the only
director originally appointed by TMP serving on the board of directors of the
combined company immediately after the merger.

Eckard Weber, M.D., a director of Ocera, is an employee ofDomain Associates,
L.L.C. ("Domain Associates") and a member of One Palmer Square Associates VI,
L.L.C., the general partner of Domain Partners VI, L.P. and DP VI Associates,
L.P. (Domain Associates, Domain Partners VI, L.P. and DP VI Associates, L.P.
are collectively referred to as "Domain"). Dr. Weber individually beneficially
owns approximately 3,030,000 shares of Ocera's common stock (which includes an
option to acquire 150,000 shares of the common stock of Ocera).Domain
beneficially owns (without including the shares beneficially owned by Dr.
Weber) in the aggregate approximately 13,609,983 shares of Ocera stock after
giving effect to the exercise of certain warrants, the conversion of
convertible notes of Ocera into preferred stock of Ocera (assuming a closing
date of June 30, 2013), and the conversion of those shares and all other
shares of preferred stock beneficially owned by Domain into common stock. Dr.
Weber is anticipated to serve as a director of the Company following the
consummation of the proposed merger.

Nina Kjellson, a director of Ocera, is a partner in InterWest Partners IX, LP
("InterWest"), a stockholder of Ocera. InterWest beneficially owns in the
aggregate approximately 3,530,891 shares of Ocera stock after giving effect to
the exercise of certain options and warrants, conversion of convertible notes
of Ocera into preferred stock of Ocera (assuming a closing date of June 30,
2013), and the conversion of those shares and all other shares of preferred
stock beneficially owned by InterWest into common stock. Nina Kjellson is
anticipated to serve as a director of the Company following the consummation
of the proposed merger.

Linda Grais is a member of the general partner of InterWest, the Chief
Executive Officer and a director of Ocera and is anticipated to be the Chief
Executive Officer and to serve as a director of the Company following the
consummation of the proposed merger. Linda Grais holds an option to acquire up
to 615,091 shares of the common stock of Ocera.

Michael F. Powell, a director of Ocera and the holder of an option to acquire
up to 150,000 shares of the common stock of Ocera, is also a managing member
of the general partner entity of Sofinnova Venture Partners VI, L.P.
("Sofinnova"). Sofinnova, as nominee for certain of its affiliated funds, is
the beneficial owner of approximately 7,297,929 shares of Ocera stock after
giving effect to the exercise of certain warrants, the conversion of
convertible notes of Ocera into preferred stock of Ocera (assuming a closing
date of June 30, 2013), and the conversion of those shares and all other
shares of preferred stock beneficially owned by Sofinnova into common stock.
Michael Powell is anticipated to serve as a director of the Company following
the consummation of the proposed merger.

Dana S. McGowan, Ocera's Chief Financial Officer and Secretary, holds options
to acquire up to 567,489 shares of Ocera stock. 

Keith Anderson, Ocera's Vice President Pharmaceutical Sciences and Chief
Operating Officer holds options to acquire up to 511,239 shares of Ocera
stock.

Certain of the holders of preferred stock of Ocera (including Domain, TMP,
InterWest and Sofinnova) also will be participating in a financing of
Tranzyme, which financing will close following the effective time of the
proposed merger.In addition to Domain, TMP, InterWest and Sofinnova, the
following entities will participate in that financing and such entities
beneficially own approximately the number of shares of Ocera stock, after
giving effect to the exercise of certain warrants, the conversion of
convertible notes of Ocera into preferred stock of Ocera (assuming a closing
date of June 30, 2013), and the conversion of those shares and all other
shares of preferred stock beneficially owned by such entity into common stock,
as parenthetically indicated: Agechem Venture Fund L.P. (2,080,549 shares);
CDIB BioScience Ventures I (520,137 shares); Cross Creek Capital, L.P.
(828,789 shares); Cross Creek Capital Employees' Fund, L.P. (81,449 shares);
FinTech GIMV Fund LP (520,137 shares); Greenspring Crossover Ventures I, L.P.
(650,357 shares); Greenspring Global Partners III, L.P. (626,516 shares);
Greenspring Global Partners III-A, L.P. (287,347 shares); and Greenspring
Global Partners III-B, L.P. (906,429 shares).

This communication does not constitute an offer to sell or the solicitation of
an offer to buy any securities or a solicitation of any vote or approval.A
definitive proxy statement and a proxy card will be filed with the SEC and
will be mailed to Tranzyme's stockholders seeking any required stockholder
approvals in connection with the proposed transactions. BEFORE MAKING ANY
VOTING OR INVESTMENT DECISION, INVESTORS AND STOCKHOLDERS ARE URGED TO READ
THE PROXY STATEMENT (INCLUDING ANY AMENDMENTS OR SUPPLEMENTS THERETO) AND ANY
OTHER RELEVANT DOCUMENTS THAT TRANZYME MAY FILE WITH THE SEC WHEN THEY BECOME
AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED
TRANSACTIONS. Stockholders may obtain, free of charge, copies of the
definitive proxy statement and any other documents filed by Tranzyme with the
SEC in connection with the proposed transactions at the SEC's website
(http://www.sec.gov), at Tranzyme's website (http://ir.tranzyme.com), or by
writing to the Secretary, Tranzyme, Inc. at 5001 South Miami Boulevard, Suite
300, Durham, North Carolina 27703.

CONTACT: Investor Inquiries
         Susan Sharpe
         Director, Corporate Communications
         Tranzyme Pharma
         (919) 328-1109
         ssharpe@tranzyme.com
        
         Angeli A. Kolhatkar
         Manager, Investor Relations
         Burns McClellan
         (212) 213-0006
         akolhatkar@burnsmc.com
        
         Media Inquiries
         Justin Jackson
         Executive Vice President
         Burns McClellan
         (212) 213-0006
         jjackson@burnsmc.com